Mobile Programming Lecture 7. Dialogs, Menus, and SharedPreferences

Transcription

1 Mobile Programming Lecture 7 Dialogs, Menus, and SharedPreferences

2 Agenda Dialogs Menus SharedPreferences

3 Android Application Components 1. Activity 2. Broadcast Receiver 3. Content Provider 4. Service

4 Dialogs A Dialog is a small window that appears in front of the current Activity It causes the Activity to lose focus Used for ProgressBars, Alerts, etc

5 Dialogs oncreatedialog called the first time the showdialog(int) method is called onpreparedialog called every time it s opened and as such will allow you to override your dialog before it is shown Without this, it will remain the same as the first time it was opened Note: As of API Level 13 oncreatedialog and onpreparedialog were deprecated in favor of DialogFragment

6 Dialogs - AlertDialog An AlertDialog is an extension of the Dialog class It is capable of constructing most Dialog user interfaces and is the suggested Dialog type

7 Dialogs - AlertDialog You should use it for Dialogs that use any of the following features A title A text message One, two, or three buttons A list of selectable items (with optional checkboxes or radio buttons)

8 Dialogs - Creating an AlertDialog public class MyDialogs extends Activity { static final int DIALOG_EXIT_ID = 1; protected Dialog oncreatedialog( int id) { Dialog dialog = null; switch (id) { case DIALOG_EXIT_ID : AlertDialog.Builder builder = new AlertDialog.Builder( this); builder.setmessage( "Do you want to exit?" ); builder.setcancelable( true); builder.setpositivebutton( "Yes", new DialogInterface.OnClickListener() { public void onclick(dialoginterface dialog, int id) { AlertDialogExample.this.finish(); ); dialog = builder.create(); break; return dialog;

9 Nothing special here, just an Dialogs int I use - to Creating identify the dialog, an AlertDialog because we can have more than one public class MyDialogs extends Activity { static final int DIALOG_EXIT_ID = 1; protected Dialog oncreatedialog(int id) { Dialog dialog = null; switch(id) { case DIALOG_EXIT_ID: AlertDialog.Builder builder = new AlertDialog.Builder(this); builder.setmessage("do you want to exit?"); builder.setcancelable(true); builder.setpositivebutton("yes", new DialogInterface.OnClickListener() { public void onclick(dialoginterface dialog, int id) { AlertDialogExample.this.finish(); ); dialog = builder.create(); break; return dialog;

10 Dialogs - Creating an AlertDialog Override this method of Activity, which is called public class MyDialogs extends Activity { static final when int DIALOG_EXIT_ID you want to show = 1; any dialog of the Activity protected Dialog oncreatedialog(int id) { Dialog dialog = null; switch(id) { case DIALOG_EXIT_ID: AlertDialog.Builder builder = new AlertDialog.Builder(this); builder.setmessage("do you want to exit?"); builder.setcancelable(true); builder.setpositivebutton("yes", new DialogInterface.OnClickListener() { public void onclick(dialoginterface dialog, int id) { AlertDialogExample.this.finish(); ); dialog = builder.create(); break; return dialog;

11 Dialogs - Creating an AlertDialog public class MyDialogs extends Activity { static final int DIALOG_EXIT_ID = 1; Switch because we can have more than one dialog, meaning we need protected Dialog oncreatedialog(int id) { to check the dialog id Dialog dialog = null; switch(id) { case DIALOG_EXIT_ID: AlertDialog.Builder builder = new AlertDialog.Builder(this); builder.setmessage("do you want to exit?"); builder.setcancelable(true); builder.setpositivebutton("yes", new DialogInterface.OnClickListener() { public void onclick(dialoginterface dialog, int id) { AlertDialogExample.this.finish(); ); dialog = builder.create(); break; return dialog;

12 Dialogs - Creating an AlertDialog public class MyDialogs extends Activity { static final int DIALOG_EXIT_ID = 1; protected Dialog oncreatedialog(int id) { Dialog dialog = null; If you want an AlertDialog, you need to build one first switch(id) { case DIALOG_EXIT_ID: AlertDialog.Builder builder = new AlertDialog.Builder(this); builder.setmessage("do you want to exit?"); builder.setcancelable(true); builder.setpositivebutton("yes", new DialogInterface.OnClickListener() { public void onclick(dialoginterface dialog, int id) { AlertDialogExample.this.finish(); ); dialog = builder.create(); break; return dialog;

13 Dialogs - Creating an AlertDialog public class MyDialogs extends Activity { static final int DIALOG_EXIT_ID = 1; protected Dialog oncreatedialog(int id) { Dialog dialog = null; Give the user a message switch(id) { case DIALOG_EXIT_ID: AlertDialog.Builder builder = new AlertDialog.Builder(this); builder.setmessage("do you want to exit?"); builder.setcancelable(true); builder.setpositivebutton("yes", new DialogInterface.OnClickListener() { public void onclick(dialoginterface dialog, int id) { AlertDialogExample.this.finish(); ); dialog = builder.create(); break; return dialog;

14 Dialogs - Creating an AlertDialog public class MyDialogs extends Activity { static final int DIALOG_EXIT_ID = 1; protected Dialog oncreatedialog(int id) { Dialog dialog = null; If true, then the user can press the back button to dismiss the dialog. switch(id) false { would force the user to make an case DIALOG_EXIT_ID: action on the dialog. AlertDialog.Builder builder = new AlertDialog.Builder(this); builder.setmessage("do you want to exit?"); builder.setcancelable(true); builder.setpositivebutton("yes", new DialogInterface.OnClickListener() { public void onclick(dialoginterface dialog, int id) { AlertDialogExample.this.finish(); ); dialog = builder.create(); break; return dialog;

15 Dialogs - Creating an AlertDialog public class MyDialogs extends Activity { static final int DIALOG_EXIT_ID = 1; protected Dialog oncreatedialog(int id) { Dialog dialog = null; Add a button, AND set a listener for switch(id) { when the button is pressed. This case DIALOG_EXIT_ID: should be the "positive" button, e.g. AlertDialog.Builder builder = new AlertDialog.Builder(this); "Yes", builder.setmessage("do "Absolutely!" you want to exit?"); builder.setcancelable(true); builder.setpositivebutton("yes", new DialogInterface.OnClickListener() { public void onclick(dialoginterface dialog, int id) { AlertDialogExample.this.finish(); ); dialog = builder.create(); break; return dialog;

16 Dialogs - Creating an AlertDialog public class MyDialogs extends Activity { static final int DIALOG_EXIT_ID = 1; protected Dialog oncreatedialog(int id) { Dialog dialog = null; switch(id) { case This DIALOG_EXIT_ID: is the listener for when the "positive" AlertDialog.Builder button is pressed, builder so = you new AlertDialog.Builder(this); should builder.setmessage("do take some kind of action. you want to exit?"); builder.setcancelable(true); builder.setpositivebutton("yes", new DialogInterface.OnClickListener() { public void onclick(dialoginterface dialog, int id) { AlertDialogExample.this.finish(); ); dialog = builder.create(); break; return dialog;

17 Dialogs - Creating an AlertDialog public class MyDialogs extends Activity { static final int DIALOG_EXIT_ID = 1; protected Dialog oncreatedialog(int id) { Dialog dialog = null; switch(id) { case DIALOG_EXIT_ID: AlertDialog.Builder builder = new AlertDialog.Builder(this); builder.setmessage("do you want to exit?"); builder.setcancelable(true); builder.setpositivebutton("yes", new DialogInterface.OnClickListener() { The Dialog isn't public created void onclick(dialoginterface dialog, int id) { until you call create() AlertDialogExample.this.finish(); ); dialog = builder.create(); break; return dialog;

18 Dialogs - Creating an AlertDialog public class MyDialogs extends Activity { static final int DIALOG_EXIT_ID = 1; protected Dialog oncreatedialog(int id) { Dialog dialog = null; switch(id) { case DIALOG_EXIT_ID: AlertDialog.Builder builder = new AlertDialog.Builder(this); builder.setmessage("do you want to exit?"); builder.setcancelable(true); builder.setpositivebutton("yes", new DialogInterface.OnClickListener() { public void onclick(dialoginterface dialog, int id) { AlertDialogExample.this.finish(); ); dialog = builder.create(); break; The type of this method is Dialog, so here we return... the Dialog! return dialog;

19 Dialogs - AlertDialog You can add up to 3 buttons on the AlertDialog by calling 1. dialog.setpositivebutton() We just used this one in the previous slides 2. dialog.setnegativebutton() "No", "Cancel" 3. dialog.setneutralbutton() "Remind me Later"

20 Dialogs - Showing a Dialog To show a Dialog on the screen, simply call showdialog(int) from within your Activity. It takes the ID of the dialog as a parameter. You can also call it from within an anonymous inner class Make sure you override the oncreatedialog() method in that Activity!

21 Dialogs - Showing a Dialog See AlertDialogExample

22 Dialogs - Dismissing a Dialog You don't want to show the Dialog to the user forever! You have to allow the user to close the Dialog somehow, even if it's not cancelable You can dismiss the Dialog by calling dismissdialog(int) from within the controlling Activity where the argument is the Dialog ID dismiss() on the Dialog object e.g. dialog.dismiss()

23 Dialogs - Showing a Dialog See DismissDialogExample

24 Dialogs - AlertDialog with a List Not only buttons! You can also add a list to your AlertDialog

25 Dialogs - AlertDialog with a List String[] countries = new String[] { "Bahamas", "Barbados", "Jamaica", "St. Martin"; public Dialog oncreatedialog(int id) { Builder builder = new AlertDialog.Builder(this); builder.settitle("select a Country"); builder.setitems(countries, new DialogInterface.OnClickListener() { public void onclick(dialoginterface dialog, int index) { Toast.makeText(getApplicationContext(), "You selected " + countries[index], Toast.LENGTH_LONG).show(); ); return builder.create();

26 We will use this Dialogs - AlertDialog with a List String array for our list String[] countries = new String[]{"Bahamas", "Barbados", "Jamaica", "St. Martin"; public Dialog oncreatedialog(int id) { Builder builder = new AlertDialog.Builder(this); builder.settitle("select a Country"); builder.setitems(countries, new DialogInterface.OnClickListener() { public void onclick(dialoginterface dialog, int index) { Toast.makeText(getApplicationContext(), "You selected " + countries[index], Toast.LENGTH_LONG).show(); ); return builder.create();

27 Dialogs - AlertDialog with a List This is a method in an Activity class, as String[] countries = new String[]{"Bahamas", "Barbados", "Jamaica", "St. Martin"; in the previous example public Dialog oncreatedialog(int id) { Builder builder = new AlertDialog.Builder(this); builder.settitle("select a Country"); builder.setitems(countries, new DialogInterface.OnClickListener() { public void onclick(dialoginterface dialog, int index) { Toast.makeText(getApplicationContext(), "You selected " + countries[index], Toast.LENGTH_LONG).show(); ); return builder.create();

28 Dialogs - AlertDialog with a List String[] countries = new String[]{"Bahamas", "Barbados", "Jamaica", "St. Martin"; We're still using an AlertDialog Builder public Dialog oncreatedialog(int id) { Builder builder = new AlertDialog.Builder(this); builder.settitle("select a Country"); builder.setitems(countries, new DialogInterface.OnClickListener() { public void onclick(dialoginterface dialog, int index) { Toast.makeText(getApplicationContext(), "You selected " + countries[index], Toast.LENGTH_LONG).show(); ); return builder.create();

29 Dialogs - AlertDialog with a List String[] countries = new String[]{"Bahamas", "Barbados", "Jamaica", "St. Martin"; public Dialog This oncreatedialog(int time we call id) { Builder setitems()! builder = new AlertDialog.Builder(this); builder.settitle("select a Country"); builder.setitems(countries, new DialogInterface.OnClickListener() { public void onclick(dialoginterface dialog, int index) { Toast.makeText(getApplicationContext(), "You selected " + countries[index], Toast.LENGTH_LONG).show(); ); return builder.create();

30 Dialogs - AlertDialog with a List String[] countries = new String[]{"Bahamas", "Barbados", "Jamaica", "St. Martin"; First argument public Dialog oncreatedialog(int id) { should be your list Builder builder = of new items AlertDialog.Builder(this); builder.settitle("select a Country"); builder.setitems(countries, new DialogInterface.OnClickListener() { public void onclick(dialoginterface dialog, int index) { Toast.makeText(getApplicationContext(), "You selected " + countries[index], Toast.LENGTH_LONG).show(); ); return builder.create();

31 Dialogs - AlertDialog with a List String[] countries = new String[]{"Bahamas", "Barbados", "Jamaica", "St. Martin"; There is more than public Dialog oncreatedialog(int id) { one Builder builder = new AlertDialog.Builder(this); OnClickListener class! builder.settitle("select a Country"); builder.setitems(countries, new DialogInterface.OnClickListener() { public void onclick(dialoginterface dialog, int index) { Toast.makeText(getApplicationContext(), "You selected " + countries[index], Toast.LENGTH_LONG).show(); ); return builder.create();

32 Dialogs - AlertDialog with a List String[] countries = new String[]{"Bahamas", "Barbados", "Jamaica", "St. Martin"; If you want to use both View.OnclickListener (for buttons) and DialogInterface.OnClickListener (for public Dialog oncreatedialog(int id) Dialogs), { then you need to be more specific Builder builder = new AlertDialog.Builder(this); here builder.settitle("select a Country"); builder.setitems(countries, new DialogInterface.OnClickListener() { public void onclick(dialoginterface dialog, int index) { Toast.makeText(getApplicationContext(), "You selected " + countries[index], Toast.LENGTH_LONG).show(); ); return builder.create();

33 Dialogs - AlertDialog with a List String[] countries = new String[]{"Bahamas", "Barbados", "Jamaica", "St. Martin"; public Dialog oncreatedialog(int id) { Builder When builder an item = in new the AlertDialog.Builder(this); list is clicked, builder.settitle("select you are Android kindly provides a Country"); you with the Dialog itself, as well builder.setitems(countries, new DialogInterface.OnClickListener() { as the index of the clicked item public void onclick(dialoginterface dialog, int index) { Toast.makeText(getApplicationContext(), "You selected " + countries[index], Toast.LENGTH_LONG).show(); ); return builder.create();

34 Dialogs - AlertDialog with a List String[] countries = new String[]{"Bahamas", "Barbados", "Jamaica", "St. Martin"; public Dialog oncreatedialog(int id) { Builder builder = new AlertDialog.Builder(this); builder.settitle("select a Country"); builder.setitems(countries, new DialogInterface.OnClickListener() { public void onclick(dialoginterface dialog, int index) { Toast.makeText(getApplicationContext(), "You selected " + countries[index], Toast.LENGTH_LONG).show(); Let's not forget to create the Dialog and return it ); return builder.create();

35 Dialogs - AlertDialog with a List See AlertDialogListExample

36 Dialogs - AlertDialog Custom View If you wish to display just a simple message to your user the setmessage() method will suffice To display a more complex view, first get a handle on the default FrameLayout custom FrameLayout custom = (FrameLayout) findviewbyid(android.r.id.custom); Add your custom View by calling addview() on the FrameLayout custom.addview(complexview, new LayoutParams(MATCH_PARENT, MATCH_PARENT);

37 Dialogs - Date/TimePicker Dialogs See DatePickerDialogExample

38 Dialogs - Custom Dialogs - SeekBar You can create your own Dialog if the standard Android Dialogs are not suitable for your needs For example, there is no SeekBar Dialog, but you can create your own See CustomDialogExample

39 Dialogs - DialogFragment Creating Dialogs by using the oncreatedialog() method of an Activity is old school Creating Dialogs by using a DialogFragment is new school

40 Dialogs - DialogFragment DialogFragment also has an oncreatedialog() callback method! i.e., both an Activity and a DialogFragment have an oncreatedialog() callback method

41 Dialogs - DialogFragment DialogFragment is slightly different than the other Fragments we've seen so far We don't need to add it to the XML Nor do we need to add it to the UI using a FragmentTransaction

42 Dialogs - DialogFragment public class MyActivity extends Activity { public void oncreate(bundle savedinstancestate) { super.oncreate(savedinstancestate); setcontentview(r.layout. main); Button button = (Button) findviewbyid(r.id. button1); button.setonclicklistener( new OnClickListener() { public void onclick(view v) { MyDialogFragment f = new MyDialogFragment(); f.show(getfragmentmanager(), "dialog"); ); public void dopositiveclick() { Toast.makeText( this, "dopositiveclick()", Toast. LENGTH_LONG).show();

43 Dialogs - DialogFragment Let's create our Activity first... public class MyActivity extends Activity { public void oncreate(bundle savedinstancestate) { super.oncreate(savedinstancestate); setcontentview(r.layout.main); Button button = (Button) findviewbyid(r.id.button1); button.setonclicklistener(new OnClickListener() { public void onclick(view v) { ); MyDialogFragment f = new MyDialogFragment(); f.show(getfragmentmanager(), "dialog"); public void dopositiveclick() { Toast.makeText(this, "dopositiveclick()", Toast.LENGTH_LONG).show();

44 Dialogs - DialogFragment public class MyActivity extends Activity { public void oncreate(bundle savedinstancestate) { super.oncreate(savedinstancestate); Let's show the Dialog when this Button is clicked! setcontentview(r.layout.main); Button button = (Button) findviewbyid(r.id.button1); button.setonclicklistener(new OnClickListener() { public void onclick(view v) { ); MyDialogFragment f = new MyDialogFragment(); f.show(getfragmentmanager(), "dialog"); public void dopositiveclick() { Toast.makeText(this, "dopositiveclick()", Toast.LENGTH_LONG).show();

45 Dialogs - DialogFragment public class MyActivity extends Activity { public void oncreate(bundle savedinstancestate) { super.oncreate(savedinstancestate); setcontentview(r.layout.main); Button button = (Button) findviewbyid(r.id.button1); The Button was just clicked at this point, so let's create a new instance of MyDialogFragment, which we will see in a few slides button.setonclicklistener(new OnClickListener() { public void onclick(view v) { ); MyDialogFragment f = new MyDialogFragment(); f.show(getfragmentmanager(), "dialog"); public void dopositiveclick() { Toast.makeText(this, "dopositiveclick()", Toast.LENGTH_LONG).show();

46 Dialogs - DialogFragment public class MyActivity extends Activity { public void oncreate(bundle savedinstancestate) { super.oncreate(savedinstancestate); setcontentview(r.layout.main); Button button = (Button) findviewbyid(r.id.button1); Just call.show() on the Fragment! This time we didn't need to use the FragmentTransaction to add the Fragment button.setonclicklistener(new OnClickListener() { public void onclick(view v) { ); MyDialogFragment f = new MyDialogFragment(); f.show(getfragmentmanager(), "dialog"); public void dopositiveclick() { Toast.makeText(this, "dopositiveclick()", Toast.LENGTH_LONG).show();

47 Dialogs - DialogFragment public class MyActivity extends Activity { public void oncreate(bundle savedinstancestate) { super.oncreate(savedinstancestate); setcontentview(r.layout.main); Button button = (Button) findviewbyid(r.id.button1); Just pass the FragmentManager and it will take care of adding and removing the Fragment for you button.setonclicklistener(new OnClickListener() { public void onclick(view v) { ); MyDialogFragment f = new MyDialogFragment(); f.show(getfragmentmanager(), "dialog"); public void dopositiveclick() { Toast.makeText(this, "dopositiveclick()", Toast.LENGTH_LONG).show();

48 Dialogs - DialogFragment public class MyActivity extends Activity { public void oncreate(bundle savedinstancestate) { super.oncreate(savedinstancestate); setcontentview(r.layout.main); Button button = (Button) findviewbyid(r.id.button1); button.setonclicklistener(new OnClickListener() { ); public void onclick(view v) { Second argument is the tag that you want to assign to the Fragment MyDialogFragment f = new MyDialogFragment(); f.show(getfragmentmanager(), "dialog"); public void dopositiveclick() { Toast.makeText(this, "dopositiveclick()", Toast.LENGTH_LONG).show();

49 Dialogs - DialogFragment public class MyActivity extends Activity { public void oncreate(bundle savedinstancestate) { super.oncreate(savedinstancestate); setcontentview(r.layout.main); Button button = (Button) findviewbyid(r.id.button1); button.setonclicklistener(new OnClickListener() { public void onclick(view v) { ); MyDialogFragment f = new MyDialogFragment(); f.show(getfragmentmanager(), "dialog"); We will get back to this! public void dopositiveclick() { Toast.makeText(this, "dopositiveclick()", Toast.LENGTH_LONG).show();

50 Dialogs - DialogFragment Let's take a look at our DialogFragment

51 Dialogs - DialogFragment public class MyDialogFragment extends DialogFragment { public Dialog oncreatedialog(bundle savedinstancestate) { Builder builder = new AlertDialog.Builder(getActivity()); builder.settitle("this is a DialogFragment!"); builder.setpositivebutton("ok", new OnClickListener() { public void onclick(dialoginterface dialog, int which) { MyActivity act = (MyActivity) getactivity(); act.dopositiveclick(); ); return builder.create();

52 Dialogs - DialogFragment! public class MyDialogFragment extends DialogFragment { public Dialog oncreatedialog(bundle savedinstancestate) { Builder builder = new AlertDialog.Builder(getActivity()); builder.settitle("this is a DialogFragment!"); builder.setpositivebutton("ok", new OnClickListener() { public void onclick(dialoginterface dialog, int which) { MyActivity act= (MyActivity) getactivity(); act.dopositiveclick(); ); return builder.create();

53 Dialogs - DialogFragment Dialog also has an oncreatedialog(), public class MyDialogFragment the proof is in the extends DialogFragment { public Dialog oncreatedialog(bundle savedinstancestate) { Builder builder = new AlertDialog.Builder(getActivity()); builder.settitle("this is a DialogFragment!"); builder.setpositivebutton("ok", new OnClickListener() { public void onclick(dialoginterface dialog, int which) { MyActivity act= (MyActivity) getactivity(); act.dopositiveclick(); ); return builder.create();

54 Dialogs - DialogFragment public class MyDialogFragment extends DialogFragment { This is how we get the Context from within a Fragment, remember!? public Dialog oncreatedialog(bundle savedinstancestate) { Builder builder = new AlertDialog.Builder(getActivity()); builder.settitle("this is a DialogFragment!"); builder.setpositivebutton("ok", new OnClickListener() { public void onclick(dialoginterface dialog, int which) { MyActivity act= (MyActivity) getactivity(); act.dopositiveclick(); ); return builder.create();

55 Dialogs - DialogFragment public class MyDialogFragment extends DialogFragment { public Dialog oncreatedialog(bundle savedinstancestate) { Builder builder = new AlertDialog.Builder(getActivity()); builder.settitle("this is a DialogFragment!"); builder.setpositivebutton("ok", new OnClickListener() { public void onclick(dialoginterface dialog, int which) { MyActivity act= (MyActivity) getactivity(); We need to act.dopositiveclick(); return a Dialog! ); return builder.create();

56 Dialogs - DialogFragment public class MyDialogFragment extends DialogFragment You've seen { this other stuff before! public Dialog oncreatedialog(bundle savedinstancestate) { Builder builder = new AlertDialog.Builder(getActivity()); builder.settitle("this is a DialogFragment!"); builder.setpositivebutton("ok", new OnClickListener() { public void onclick(dialoginterface dialog, int which) { MyActivity act= (MyActivity) getactivity(); act.dopositiveclick(); ); return builder.create();

57 Dialogs - DialogFragment public class MyDialogFragment extends DialogFragment { public Dialog oncreatedialog(bundle savedinstancestate) { Builder builder = new AlertDialog.Builder(getActivity()); builder.settitle("this is a DialogFragment!"); builder.setpositivebutton("ok", new OnClickListener() { The button in the Dialog has now been clicked! What do we do next? public void onclick(dialoginterface dialog, int which) { ); MyActivity act= (MyActivity) getactivity(); act.dopositiveclick(); return builder.create();

58 Dialogs - DialogFragment public class MyDialogFragment extends DialogFragment { public Dialog oncreatedialog(bundle savedinstancestate) { Builder builder = new AlertDialog.Builder(getActivity()); builder.settitle("this is a DialogFragment!"); builder.setpositivebutton("ok", new OnClickListener() { Let's get a handle on the Activity containing this Fragment public void onclick(dialoginterface dialog, int which) { ); MyActivity act= (MyActivity) getactivity(); act.dopositiveclick(); return builder.create();

59 Dialogs - DialogFragment public class MyDialogFragment extends DialogFragment { public Dialog oncreatedialog(bundle savedinstancestate) { Builder builder = new AlertDialog.Builder(getActivity()); builder.settitle("this is a DialogFragment!"); builder.setpositivebutton("ok", new OnClickListener() { Let's call our own custom method, public void dopositiveclick() onclick(dialoginterface on dialog, int which) { the Activity MyActivity act= (MyActivity) getactivity(); ); act.dopositiveclick(); return builder.create();

60 Dialogs - DialogFragment public class MyActivity extends Activity { public void oncreate(bundle savedinstancestate) { super.oncreate(savedinstancestate); setcontentview(r.layout.main); Button button = (Button) findviewbyid(r.id.button1); button.setonclicklistener(new OnClickListener() { public void onclick(view v) { ); MyDialogFragment f = new MyDialogFragment(); f.show(getfragmentmanager(), "dialog"); Which takes us back here, back to our Activity. public void dopositiveclick() { Toast.makeText(this, "dopositiveclick()", Toast.LENGTH_LONG).show();

61 Dialogs - DialogFragment public class MyActivity extends Activity { public void oncreate(bundle savedinstancestate) { super.oncreate(savedinstancestate); setcontentview(r.layout.main); Button button = (Button) findviewbyid(r.id.button1); button.setonclicklistener(new OnClickListener() { public void onclick(view v) { ); public void dopositiveclick() { MyDialogFragment f = new MyDialogFragment(); f.show(getfragmentmanager(), "dialog"); Simply make a Toast as evidence that we were successful Toast.makeText(this, "dopositiveclick()", Toast.LENGTH_LONG).show();

62 Dialogs - DialogFragment Note that we don't need to override oncreateview() or onactivitycreated() methods of a DialogFragment You may choose to override oncreateview() and return a View if you want to create some custom Dialog without using oncreatedialog() I'll leave it up to the Android developer's website to explain it if anyone is interested in doing so

63 Dialogs - DialogFragment See FragmentDialogExample

64 Menu Options In Android 2.3.x and below, clicking on the dedicated Menu button allows the user to reveal menu options In Android 3.0 and above, the options menu is presented by way of an action bar The dedicated Menu button is deprecated and some devices just do not have one

65 Menu Options - Creating one <= 2.3.x Right click on your project Select New > Android Resource File In the Resource Type drop down list, select Menu Enter a Filename and click Finish Within the <menu> </menu> tags, create a new <item> tag Edit the android:id and android:title attributes as appropriate Repeat to add additional menu options

66 Menu Options - Creating one <= 2.3.x We will use this Menu XML file, main_menu.xml, for our example <?xml version="1.0" encoding="utf-8"?> <menu xmlns:android=" <item android:id="@+id/set_text" android:title="@string/set_text_opt"/> <item android:id="@+id/close" android:title="@string/close_opt" /> </menu>

67 Menu Options - Creating one <= 2.3.x public void oncreate(bundle savedinstancestate) { super.oncreate(savedinstancestate); setcontentview(r.layout.main); public boolean oncreateoptionsmenu(menu menu) { MenuInflater inflater = getmenuinflater(); inflater.inflate(r.menu.main_menu, menu); return true;

68 Menu Options - Creating one <= 2.3.x public void oncreate(bundle savedinstancestate) { super.oncreate(savedinstancestate); setcontentview(r.layout.main); Override this Activity method public boolean oncreateoptionsmenu(menu menu) { MenuInflater inflater = getmenuinflater(); inflater.inflate(r.menu.main_menu, menu); return true;

69 Menu Options - Creating one <= 2.3.x public void oncreate(bundle savedinstancestate) { super.oncreate(savedinstancestate); setcontentview(r.layout.main); Similar to a LayoutInflater, but for Menus instead public boolean oncreateoptionsmenu(menu menu) { MenuInflater inflater = getmenuinflater(); inflater.inflate(r.menu.main_menu, menu); return true;

70 Menu Options - Creating one <= 2.3.x public void oncreate(bundle savedinstancestate) { super.oncreate(savedinstancestate); setcontentview(r.layout.main); public Show boolean the Menu now oncreateoptionsmenu(menu menu) { MenuInflater inflater = getmenuinflater(); inflater.inflate(r.menu.main_menu, menu); return true;

71 Menu Options - Creating one <= 2.3.x public void oncreate(bundle savedinstancestate) { super.oncreate(savedinstancestate); setcontentview(r.layout.main); This is the Menu XML file that we created previously public boolean oncreateoptionsmenu(menu menu) { MenuInflater inflater = getmenuinflater(); inflater.inflate(r.menu.main_menu, menu); return true;

72 Menu Options - Creating one <= 2.3.x public void oncreate(bundle savedinstancestate) { super.oncreate(savedinstancestate); setcontentview(r.layout.main); This is given as argument to oncreateoptionsmenu, so use it as argument to inflate the menu public boolean oncreateoptionsmenu(menu menu) { MenuInflater inflater = getmenuinflater(); inflater.inflate(r.menu.main_menu, menu); return true;

73 Menu Options - Creating one <= 2.3.x public void oncreate(bundle savedinstancestate) { super.oncreate(savedinstancestate); setcontentview(r.layout.main); public boolean oncreateoptionsmenu(menu menu) { Return true if you want the MenuInflater menu to be displayed, inflater false = getmenuinflater(); if you don't inflater.inflate(r.menu.main_menu, menu); return true;

74 Menu Options - Creating one <= 2.3.x This is enough for the Menu to be displayed on the screen when the user presses the Menu button If you want to take action after an option is selected, then you need to override the onoptionsitemselected() method of Activity

75 Menu Options - Creating one <= 2.3.x public boolean onoptionsitemselected(menuitem item) { switch (item.getitemid()) { case R.id.set_text: TextView tv = (TextView) findviewbyid(r.id. textview1); tv.settext("first Option Selected!" ); break; case R.id.close: Toast.makeText( this, "Goodbye!", Toast.LENGTH_LONG).show(); finish(); break; return true;

76 Menu Options - Creating one <= 2.3.x public boolean onoptionsitemselected(menuitem item) { switch (item.getitemid()) { We override this method of Activity case R.id.set_text: TextView tv = (TextView) findviewbyid(r.id.textview1); tv.settext("first Option Selected!"); break; case R.id.close: Toast.makeText(this, "Goodbye!", Toast.LENGTH_LONG).show(); finish(); break; return true;

77 Menu Options - Creating one <= 2.3.x Which menu item was selected? public boolean onoptionsitemselected(menuitem item) { switch (item.getitemid()) { case R.id.set_text: TextView tv = (TextView) findviewbyid(r.id.textview1); tv.settext("first Option Selected!"); break; case R.id.close: Toast.makeText(this, "Goodbye!", Toast.LENGTH_LONG).show(); finish(); break; return true;

78 Menu Options - Creating one <= 2.3.x Here we just changed the text of a public boolean onoptionsitemselected(menuitem item) { TextView when the item switch (item.getitemid()) { R.id.set_text is selected case R.id.set_text: TextView tv = (TextView) findviewbyid(r.id.textview1); tv.settext("first Option Selected!"); break; case R.id.close: Toast.makeText(this, "Goodbye!", Toast.LENGTH_LONG).show(); finish(); break; return true;

79 Menu Options - Creating one <= 2.3.x public boolean onoptionsitemselected(menuitem item) { switch (item.getitemid()) { case R.id.set_text: TextView tv = (TextView) findviewbyid(r.id.textview1); tv.settext("first Option Selected!"); Here we break; close our app when item R.id.close is selected case R.id.close: Toast.makeText(this, "Goodbye!", Toast.LENGTH_LONG).show(); finish(); break; return true;

80 Menu Options - Creating one <= 2.3.x See MenuOptionsExample

81 Menu Options - Creating one <= 2.3.x You can change the menu options that show up at runtime

82 Menu Options - Creating one >= 3.0 For Android 3.0 and higher... We ll take a closer look at this when we talk about Material Design

83 Context Menu You can provide a context menu for any View, but they are most often used for items in a ListView GridView Other View collections in which the user can perform direct actions on each item.

84 Context Menu - Creating one When creating a Context Menu, you can create a Menu XML file in the same way you do for an Options Menu

85 Context Menu - Creating one We will use the following XML file for our example <?xml version= "1.0" encoding="utf-8"?> <menu xmlns:android= " > <item android:id="@+id/edit_option" android:title= "Edit"></item> <item android:id="@+id/share_option" android:title= "Share"></item> <item android:id="@+id/delete_option" android:title= "Delete"></item> </menu> All of the callback methods in this example are declared within our ListActivity

86 Context Menu - Creating one As a reminder, A ListActivity extends Activity It already has a ListView, so you don't need to add one Instead of getting a handle on the ListView by calling findviewbyid(r.id.list_view_id) You simply call getlistview() instead

87 Context Menu - Creating one public class ContextMenuExample extends ListActivity { String[] entries = new String[] { "Martin", "Anderson", "Junior", "George", "Dan" ; public void oncreate(bundle savedinstancestate) { super.oncreate(savedinstancestate); this.setlistadapter( new ArrayAdapter<String>( this, android.r.layout. simple_list_item_1, entries)); registerforcontextmenu(getlistview());

88 Context Menu - Creating one We will use this String array to populate our List public class ContextMenuExample extends ListActivity { String[] entries = new String[] { "Martin", "Anderson", "Junior", "George","Dan"; public void oncreate(bundle savedinstancestate) { super.oncreate(savedinstancestate); this.setlistadapter(new ArrayAdapter<String>(this, android.r.layout.simple_list_item_1, entries)); registerforcontextmenu(getlistview());

89 Context Menu - Creating one public class ContextMenuExample extends ListActivity { String[] entries = new String[] {"Martin", "Anderson", "Junior", "George", "Dan"; Populate the ListView public here void oncreate(bundle savedinstancestate) { super.oncreate(savedinstancestate); this.setlistadapter(new ArrayAdapter<String>(this, android.r.layout.simple_list_item_1, entries)); registerforcontextmenu(getlistview());

90 Context Menu - Creating one public class ContextMenuExample extends ListActivity { String[] entries = new String[] {"Martin", "Anderson", "Junior", "George", "Dan"; public void oncreate(bundle savedinstancestate) { super.oncreate(savedinstancestate); Register the ListView with a this.setlistadapter(new Context Menu, now the menu ArrayAdapter<String>(this, will show up when android.r.layout.simple_list_item_1, long entries)); press on the ListView registerforcontextmenu(getlistview());

91 Context Menu - Creating one public class ContextMenuExample extends ListActivity { String[] entries = new String[] { "Martin", "Anderson", "Junior", oncreate() from previous "George", slide is here "Dan";... public void oncreatecontextmenu(contextmenu menu, View v, ContextMenuInfo menuinfo) { super.oncreatecontextmenu(menu, v, menuinfo); MenuInflater inflater = getmenuinflater(); inflater.inflate(r.menu.context_menu, menu);...

92 Context Menu - Creating one public class ContextMenuExample extends ListActivity { String[] entries = new String[] { "Martin", "Anderson", "Junior",... "George", "Dan" ; public void oncreatecontextmenu(contextmenu menu, View v, Override this method. It is called when the Context Menu for View v is being built super.oncreatecontextmenu(menu, v, menuinfo); MenuInflater inflater = getmenuinflater(); inflater.inflate(r.menu.context_menu, menu); ContextMenuInfo menuinfo) {...

93 Context Menu - Creating one public class ContextMenuExample extends ListActivity { String[] entries = new String[] { "Martin", "Anderson", "Junior", "George", "Dan" ;... public You've void seen oncreatecontextmenu(contextmenu this menu, View v, before ContextMenuInfo menuinfo) { super.oncreatecontextmenu(menu, v, menuinfo); MenuInflater inflater = getmenuinflater(); inflater.inflate(r.menu.context_menu, menu);...

94 Context Menu - Creating one public class ContextMenuExample extends ListActivity { String[] entries = new String[] { "Martin", "Anderson", "Junior", "George", "Dan" ;... public void oncreatecontextmenu(contextmenu menu, View v, ContextMenuInfo menuinfo) { super.oncreatecontextmenu(menu, v, menuinfo); MenuInflater inflater = getmenuinflater(); oncontextitemselected() on inflater.inflate(r.menu.context_menu, menu); the next slide goes here...

95 Override this method Context Menu - Creating one of Activity public boolean oncontextitemselected(menuitem item) { AdapterContextMenuInfo info = (AdapterContextMenuInfo) item.getmenuinfo(); TextView tv = (TextView) getlistview().getadapter().getview(info.position, null, null); switch(item.getitemid()) { case R.id.edit_option: /* Edit option selected */ break; case R.id.share_option: /* Share option selected */ break; case R.id.delete_option: /* Edit option selected */ break; return true;

96 This Object has information about the Context Menu, NOT the item in the List Context Menu - Creating one public boolean oncontextitemselected(menuitem item) { AdapterContextMenuInfo info = (AdapterContextMenuInfo) item.getmenuinfo(); TextView tv = (TextView) getlistview().getadapter().getview(info.position, null, null); switch(item.getitemid()) { case R.id.edit_option: /* Edit option selected */ break; case R.id.share_option: /* Share option selected */ break; case R.id.delete_option: /* Edit option selected */ break; return true;

97 Context Menu - Creating one This Object will have public boolean oncontextitemselected(menuitem item) { AdapterContextMenuInfo info = (AdapterContextMenuInfo) item.getmenuinfo(); TextView tv = (TextView) getlistview().getadapter().getview(info.position, null, null); switch(item.getitemid()) { information about the item pressed case R.id.edit_option: /* Edit option selected */ break; case R.id.share_option: /* Share option selected */ break; case R.id.delete_option: return true; /* Edit option selected */ break;

98 Context Menu - Creating one We can get a handle on the item in the ListView by using public boolean oncontextitemselected(menuitem item) { info.position AdapterContextMenuInfo info = (AdapterContextMenuInfo) item.getmenuinfo(); TextView tv = (TextView) getlistview().getadapter().getview(info.position, null, null); switch(item.getitemid()) { case R.id.edit_option: /* Edit option selected */ break; case R.id.share_option: /* Share option selected */ break; case R.id.delete_option: return true; /* Edit option selected */ break;

99 Context Menu - Creating one public boolean oncontextitemselected(menuitem item) { info.position tells us which item AdapterContextMenuInfo info = (AdapterContextMenuInfo) item.getmenuinfo(); was pressed, this is how we tell TextView which tv = Menu (TextView) Item was getlistview().getadapter().getview(info.position, pressed null, null); switch(item.getitemid()) { case R.id.edit_option: /* Edit option selected */ break; case R.id.share_option: /* Share option selected */ break; case R.id.delete_option: /* Edit option selected */ break; return true;

100 Context Menu - Creating one public boolean oncontextitemselected(menuitem item) { AdapterContextMenuInfo info = (AdapterContextMenuInfo) item.getmenuinfo(); TextView tv = (TextView) getlistview().getadapter().getview(info.position, null, null); switch(item.getitemid()) { case R.id.edit_option: /* Edit option selected */ break; case R.id.share_option: /* Share option selected */ break; case R.id.delete_option: return true; /* Edit option selected */ break; By combining info.position and item.getitemid(), we know the action needs to be performed on the item

101 Context Menu - Creating one See ContextMenuExample

102 Preferences - SharedPreferences SharedPreferences represent 1 of the 5 methods for Data Storage in Android It stores key-value pairs of primitive data types boolean, int, float, long, String Data persists even if your app has been fully terminated

103 Preferences - SharedPreferences SharedPreferences are only available to app that created that created them!

104 Preferences - SharedPreferences public class SharedPrefsExample extends Activity { public static final String PREFS_NAME = "MyPrefsFile"; protected void oncreate(bundle state){ super.oncreate(state); SharedPreferences settings = getsharedpreferences(prefs_name, 0); boolean silent = settings.getboolean("silentmode", false); setsilent(silent); protected void onstop(){ super.onstop(); SharedPreferences settings = getsharedpreferences(prefs_name, 0); SharedPreferences.Editor editor = settings.edit(); editor.putboolean("silentmode", msilentmode); editor.commit();

105 Preferences - SharedPreferences public class SharedPrefsExample extends Activity { public static final String PREFS_NAME = "MyPrefsFile"; The desired name of your SharedPreferences file protected void oncreate(bundle state){ super.oncreate(state); SharedPreferences settings = getsharedpreferences(prefs_name, 0); boolean silent = settings.getboolean("silentmode", false); setsilent(silent); protected void onstop(){ super.onstop(); SharedPreferences settings = getsharedpreferences(prefs_name, 0); SharedPreferences.Editor editor = settings.edit(); editor.putboolean("silentmode", msilentmode); editor.commit();

106 Preferences - SharedPreferences public class SharedPrefsExample extends Activity { public static final String PREFS_NAME = "MyPrefsFile"; You can get a SharedPreferences file by name by calling this method protected void oncreate(bundle state){ super.oncreate(state); SharedPreferences settings = getsharedpreferences(prefs_name, 0); boolean silent = settings.getboolean("silentmode", false); setsilent(silent); protected void onstop(){ super.onstop(); SharedPreferences settings = getsharedpreferences(prefs_name, 0); SharedPreferences.Editor editor = settings.edit(); editor.putboolean("silentmode", msilentmode); editor.commit();

107 Preferences - SharedPreferences public class SharedPrefsExample extends Activity { public static final String PREFS_NAME = "MyPrefsFile"; protected void oncreate(bundle state){ super.oncreate(state); The second argument is the mode SharedPreferences settings = getsharedpreferences(prefs_name, 0); boolean silent = settings.getboolean("silentmode", false); setsilent(silent); protected void onstop(){ super.onstop(); SharedPreferences settings = getsharedpreferences(prefs_name, 0); SharedPreferences.Editor editor = settings.edit(); editor.putboolean("silentmode", msilentmode); editor.commit();

108 Preferences - SharedPreferences public class SharedPrefsExample extends Activity { public static final String PREFS_NAME = "MyPrefsFile"; protected void oncreate(bundle state){ super.oncreate(state); If the SharedPreferences file doesn't exist at this point, it will be created for you SharedPreferences settings = getsharedpreferences(prefs_name, 0); boolean silent = settings.getboolean("silentmode", false); setsilent(silent); protected void onstop(){ super.onstop(); SharedPreferences settings = getsharedpreferences(prefs_name, 0); SharedPreferences.Editor editor = settings.edit(); editor.putboolean("silentmode", msilentmode); editor.commit();

109 Preferences - SharedPreferences public class SharedPrefsExample extends Activity { public static final String PREFS_NAME = "MyPrefsFile"; Try to get the boolean value protected void oncreate(bundle state){ "silentmode", "silentmode" is the key. You decide on the name of the key. super.oncreate(state); "silentmode" is not a keyword here SharedPreferences settings = getsharedpreferences(prefs_name, 0); boolean silent = settings.getboolean("silentmode", false); setsilent(silent); protected void onstop(){ super.onstop(); SharedPreferences settings = getsharedpreferences(prefs_name, 0); SharedPreferences.Editor editor = settings.edit(); editor.putboolean("silentmode", msilentmode); editor.commit();

110 Preferences - SharedPreferences public class SharedPrefsExample extends Activity { public static final String PREFS_NAME = "MyPrefsFile"; protected void oncreate(bundle state){ super.oncreate(state); SharedPreferences settings = getsharedpreferences(prefs_name, 0); boolean silent = settings.getboolean("silentmode", false); setsilent(silent); protected void onstop(){ super.onstop(); If the key doesn't exist (could be because the file was just created in the previous line of code), then this will be the value returned SharedPreferences settings = getsharedpreferences(prefs_name, 0); SharedPreferences.Editor editor = settings.edit(); editor.putboolean("silentmode", msilentmode); editor.commit();

111 Preferences - SharedPreferences public class SharedPrefsExample extends Activity { public static final String PREFS_NAME = "MyPrefsFile"; protected void oncreate(bundle state){ An imaginary method that you super.oncreate(state); created to change the volume setting of the device to silent SharedPreferences settings = getsharedpreferences(prefs_name, 0); boolean silent = settings.getboolean("silentmode", false); setsilent(silent); protected void onstop(){ super.onstop(); SharedPreferences settings = getsharedpreferences(prefs_name, 0); SharedPreferences.Editor editor = settings.edit(); editor.putboolean("silentmode", msilentmode); editor.commit();

112 Preferences - SharedPreferences public class SharedPrefsExample extends Activity { public static final String PREFS_NAME = "MyPrefsFile"; protected void oncreate(bundle state){ super.oncreate(state); SharedPreferences settings = getsharedpreferences(prefs_name, 0); boolean We want silent data = to settings.getboolean("silentmode", persist even false); setsilent(silent); after the app has been terminated, so let's Override onstop() protected void onstop(){ super.onstop(); SharedPreferences settings = getsharedpreferences(prefs_name, 0); SharedPreferences.Editor editor = settings.edit(); editor.putboolean("silentmode", msilentmode); editor.commit();

113 Preferences - SharedPreferences public class SharedPrefsExample extends Activity { public static final String PREFS_NAME = "MyPrefsFile"; protected void oncreate(bundle state){ super.oncreate(state); SharedPreferences settings = getsharedpreferences(prefs_name, 0); boolean silent = settings.getboolean("silentmode", false); setsilent(silent); protected void onstop(){ super.onstop(); Get a handle on our SharedPreferences again, which should have the "silentmode" value set at this point SharedPreferences settings = getsharedpreferences(prefs_name, 0); SharedPreferences.Editor editor = settings.edit(); editor.putboolean("silentmode", msilentmode); editor.commit();

114 Preferences - SharedPreferences public class SharedPrefsExample extends Activity { public static final String PREFS_NAME = "MyPrefsFile"; protected void oncreate(bundle state){ super.oncreate(state); SharedPreferences settings = getsharedpreferences(prefs_name, 0); boolean silent = settings.getboolean("silentmode", false); setsilent(silent); protected void onstop(){ If we want to modify the SharedPreferences, we need to use a super.onstop(); SharedPreferences Editor SharedPreferences settings = getsharedpreferences(prefs_name, 0); SharedPreferences.Editor editor = settings.edit(); editor.putboolean("silentmode", msilentmode); editor.commit();

115 Preferences - SharedPreferences public class SharedPrefsExample extends Activity { public static final String PREFS_NAME = "MyPrefsFile"; protected void oncreate(bundle state){ super.oncreate(state); SharedPreferences settings = getsharedpreferences(prefs_name, 0); boolean silent = settings.getboolean("silentmode", false); setsilent(silent); protected void onstop(){ Let's set the value value of silentmode super.onstop(); to the imaginary boolean value msilentmode SharedPreferences settings = getsharedpreferences(prefs_name, 0); SharedPreferences.Editor editor = settings.edit(); editor.putboolean("silentmode", msilentmode); editor.commit();

116 Preferences - SharedPreferences public class SharedPrefsExample extends Activity { public static final String PREFS_NAME = "MyPrefsFile"; protected void oncreate(bundle state){ super.oncreate(state); SharedPreferences settings = getsharedpreferences(prefs_name, 0); boolean silent = settings.getboolean("silentmode", false); setsilent(silent); protected void onstop(){ super.onstop(); Don't forget to save your SharedPreferences changes to the file! settings = getsharedpreferences(prefs_name, 0); SharedPreferences.Editor editor = settings.edit(); editor.putboolean("silentmode", msilentmode); editor.commit();

117 Preferences - SharedPreferences See SharedPrefsExample

118 Preferences - PreferenceActivity If you want to provide the user with a UI for changing preferences, you can use a PreferenceActivity in combination with SharedPreferences To create a PreferenceActivity, first create a Preference XML file

119 Preferences - PreferenceActivity File > New > Android Resource File Resource Type: XML Enter the file name, e.g. preferences.xml This creates a file in the /res/xml folder Ensure the preferences.xml file has a <PreferenceScreen> as the root element Add the various types of preferences as necessary e.g. EditTextPreference, CheckBoxPreference, Set the attributes for each preference as necessary

120 Preferences - PreferenceActivity We will use this preferences.xml file for our example <?xml version="1.0" encoding="utf-8"?> <PreferenceScreen xmlns:android=" <EditTextPreference android:dialogtitle="username" android:dialogmessage="please enter your Username" android:summary="username for logging in to this app" android:title="username" android:key="username"/> <CheckBoxPreference android:summaryoff="i do not want your spam" android:key="spam" android:title="spam" android:summaryon="sign me up for spam"/> </PreferenceScreen>

121 Preferences - PreferenceActivity Creating a PreferenceActivity is easy!

122 Preferences - PreferenceActivity public class Preferences extends PreferenceActivity { public void oncreate(bundle savedinstancestate) { super.oncreate(savedinstancestate); addpreferencesfromresource(r.xml.preferences);

123 Preferences - PreferenceActivity Extend PreferenceActivity public class Preferences extends PreferenceActivity { public void oncreate(bundle savedinstancestate) { super.oncreate(savedinstancestate); addpreferencesfromresource(r.xml.preferences);

124 Preferences - PreferenceActivity public class Preferences extends PreferenceActivity { From the preferences.xml file we added previously public void oncreate(bundle savedinstancestate) { super.oncreate(savedinstancestate); addpreferencesfromresource(r.xml.preferences);

125 Preferences - PreferenceActivity In your main Activity, you can get the Preferences without specifying the name of the XML file

126 Preferences - PreferenceActivity public class MainActivity extends Activity { SharedPreferences mprefs; public void oncreate(bundle savedinstancestate) { super.oncreate(savedinstancestate); mprefs = PreferenceManager.getDefaultSharedPreferences( getbasecontext()); String username = mprefs.getstring( "username", "None");

127 Preferences - PreferenceActivity public class MainActivity extends Activity { SharedPreferences mprefs; This will allow you to access the preference settings, even if you have more than one preference XML file public associated void oncreate(bundle with a PreferenceActivity savedinstancestate) { super.oncreate(savedinstancestate); mprefs = PreferenceManager.getDefaultSharedPreferences( getbasecontext()); String username = mprefs.getstring("username","none");

128 Preferences - PreferenceActivity public class MainActivity extends Activity { SharedPreferences mprefs; These preferences will automatically save when the user public void interacts oncreate(bundle with them! savedinstancestate) { super.oncreate(savedinstancestate); mprefs = PreferenceManager.getDefaultSharedPreferences( getbasecontext()); String username = mprefs.getstring("username","none");

129 Preferences - PreferenceActivity See PreferenceActivityExample

130 Preferences - PreferenceActivity You can also add a Listener for when a Preference has been changed When a Preference is changed, you may need to update certain values tied to these Preferences

131 Preferences - PreferenceFragment Android 3.0 and higher PreferenceFragment

132 References The Busy Coder's Guide to Android Development - Mark Murphy Android Developers The Mobile Lab at Florida State University