Computer Science 251. iphone Application Development. Autorotation, Popover Controllers, Modal Controllers

Transcription

1 Computer Science 251 iphone Application Development Autorotation, Popover Controllers, Modal Controllers

2 Two Types of Orientation Device: physically upside down, rotated left, on its back, etc. Can be set for deployment. Interface: Portrait (up or down), landscape (left or right). Can be detected, enabled, or disabled under program control.

3 Device Defaults for ipad and iphone iphone allows all orientations but upside down ipad allows all 4 A universal app will support each one independently

4 Override This Controller Method - (NSUInteger)supportedInterfaceOrientations if ([UIDevice currentdevice].userinterfaceidiom == UIUserInterfaceIdiomPad) return UIInterfaceOrientationMaskAll; else return UIInterfaceOrientationMaskAllButUpsideDown; This default behavior corresponds to the device defaults, but you can alter it under program control

5 Example: Landscape Only - (NSUInteger)supportedInterfaceOrientations // On all devices, return left and right return UIInterfaceOrientationMaskLandscapeLeft UIInterfaceOrientationMaskLandscapeRight;

6 iphone Landscape Camera Not! - (void)prepareviewsfororientation:(uiinterfaceorientation)orientation // Is it an ipad? No preparation necessary if ([UIDevice currentdevice].userinterfaceidiom == UIUserInterfaceIdiomPad) return; // Is it landscape? if (UIInterfaceOrientationIsLandscape(orientation)) self.imageview.hidden = YES; self.camerabutton.enabled = NO; else self.imageview.hidden = NO; self.camerabutton.enabled = YES;

7 iphone Landscape Camera Not! - (void)willanimaterotationtointerfaceorientation: (UIInterfaceOrientation)toInterfaceOrientation duration:(nstimeinterval)duration [self prepareviewsfororientation:tointerfaceorientation]; - (void)viewwillappear:(bool)animated [super viewwillappear:animated]; UIInterfaceOrientation io = [[UIApplication sharedapplication] statusbarorientation]; [self prepareviewsfororientation:io];...

8 Popover Controllers Available only for ipad apps Take advantage of extra screen real estate Pops up a bordered window that floats above the rest of the view

9 Image picker in a popover controller

10 Conform to Popover BNRDetailViewController () <UINavigationControllerDelegate, UIImagePickerControllerDelegate, UITextFieldDelegate, (strong, nonatomic) UIPopoverController (weak, nonatomic) IBOutlet UITextField *namefield;

11 In the takepicture: Method imagepicker.delegate = self; // Place image picker on the screen // Check for ipad device before instantiating the popover controller if ([UIDevice currentdevice].userinterfaceidiom == UIUserInterfaceIdiomPad) // Create a new popover controller that will display the imagepicker self.imagepickerpopover = [[UIPopoverController alloc] initwithcontentviewcontroller:imagepicker]; self.imagepickerpopover.delegate = self; // Display the popover controller; sender // is the camera bar button item [self.imagepickerpopover presentpopoverfrombarbuttonitem:sender permittedarrowdirections:uipopoverarrowdirectionany animated:yes]; else [self presentviewcontroller:imagepicker animated:yes completion:null]; Use popover only if device is an ipad

12 Modal Controllers Manage a view that pops up over another view and does not relinquish control until the user taps Done or Cancel Can use a navigation bar but is not part of a navigation stack Good for one-off I/O interactions

13 Alert View is a modal view

14 Enter a new BNR item in a modal view

15 A New Initializer in Detail View - (instancetype)initfornewitem:(bool)isnew self = [super initwithnibname:nil bundle:nil]; if (self) if (isnew) UIBarButtonItem *doneitem = [[UIBarButtonItem alloc] initwithbarbuttonsystemitem:uibarbuttonsystemitemdone target:self action:@selector(save:)]; self.navigationitem.rightbarbuttonitem = doneitem; UIBarButtonItem *cancelitem = [[UIBarButtonItem alloc] initwithbarbuttonsystemitem:uibarbuttonsystemitemcancel target:self action:@selector(cancel:)]; self.navigationitem.leftbarbuttonitem = cancelitem; return self;

16 Tap the New Button - (IBAction)addNewItem:(id)sender BNRItem *newitem = [[BNRItemStore sharedstore] createitem]; BNRDetailViewController *detailviewcontroller = [[BNRDetailViewController alloc] initfornewitem:yes]; detailviewcontroller.item = newitem; UINavigationController *navcontroller = [[UINavigationController alloc] initwithrootviewcontroller:detailviewcontroller]; navcontroller.modalpresentationstyle = UIModalPresentationFormSheet; [self presentviewcontroller:navcontroller animated:yes completion:null]; Two presentation styles: form sheet and page sheet

17 Save, Cancel, Dismiss - (void)save:(id)sender [self.presentingviewcontroller dismissviewcontrolleranimated:yes completion:null]; - (void)cancel:(id)sender // If the user cancelled, then remove the BNRItem from the store [[BNRItemStore sharedstore] removeitem:self.item]; [self.presentingviewcontroller dismissviewcontrolleranimated:yes completion:null];

18 Problem: Items View Does Not Update In page sheet style, the modal view completely covers the items view, so the latter s viewwillappear triggers when the modal view is dismissed, and items are reloaded But in form sheet style, only part of the items view is covered, so viewwillappear is NOT triggered

19 Blocks to the Rescue! A block is a chunk of code that is passed as an argument to a method, and later executed within the method (strategy pattern) Set a property in the detail view to a block that reloads the items view, and pass this block to the dismissal method of the detail view

20 Header of dismissal method: - (void)dismissviewcontrolleranimated:(bool)flag completion:(void (^)(void))completion; In detail view (nonatomic, copy) void (^dismissblock)(void); In items view controller: - (IBAction)addNewItem:(id)sender // Create a new BNRItem and add it to the store BNRItem *newitem = [[BNRItemStore sharedstore] createitem]; BNRDetailViewController *detailviewcontroller = [[BNRDetailViewController alloc] initfornewitem:yes]; detailviewcontroller.item = newitem; detailviewcontroller.dismissblock = ^ [self.tableview reloaddata]; ;

21 Save, Cancel, Dismiss - (void)save:(id)sender [self.presentingviewcontroller dismissviewcontrolleranimated:yes completion:self.dismissblock]; - (void)cancel:(id)sender // If the user cancelled, then remove the BNRItem from the store [[BNRItemStore sharedstore] removeitem:self.item]; [self.presentingviewcontroller dismissviewcontrolleranimated:yes completion:self.dismissblock];