Java FX. Properties and Bindings

Transcription

1 Java FX Properties and Bindings

2 Properties : something that holds data data can be simple like an int or complex like a list data structure this data can be used to update other things when it changes

3 Properties : something that holds data data can be simple like an int or complex like a list data structure this data can be used to update other things when it changes. addlistener(. ); removelistener (. );.. // inherited from parents What What does does this this look look like? like?

4 Properties : something that holds data data can be simple like an int or complex like a list data structure this data can be used to update other things when it changes. addlistener(. ); // inherited from parents removelistener (. );.. EventHandling What does this EventHandling that that we we looked looked at look like? at last last week. week.

5 Properties : something that holds data data can be simple like an int or complex like a list data structure this data can be used to update other things when it changes Simple Integer Simple Double Simple String Simple List.

6 Properties : something that holds data data can be simple like an int or complex like a list data structure this data can be used to update other things when it changes. get ( ); set ( value);.. Simple Integer Simple Double Simple String Simple List.

7 Properties : something that holds data data can be simple like an int or complex like a list data structure this data can be used to update other things when it changes Used in most of the FX classes Simple Integer Simple Double Simple String Simple List.

8 Binding and Properties : something that holds data data can be simple like an int or complex like a list data structure this data can be used to update other things when it changes Bind: connects one property to another property a.bind( b ); // the value of a will always be changed to b as b changes once this binding relationship is made, the data in a will be updated automatically as the property b is changed connection can be one way or two way

9 Binding and Properties : something that holds data data can be simple like an int or complex like a list data structure this data can be used to update other things when it changes Bind: connects one property to another property a.bind( b ); // the value of a will always be changed to b as b changes Most of the FX objects will have properties that you can use to bind

10 Binding and Properties Example The radius property of the circle can be bound to the value property of the slider as the slider is moved, the circle will grow or shrink

11 Binding and Properties Example The radius property of the circle can be bound to the value property of the slider as the slider is moved, the circle will grow or shrink

12 public void start(stage stage) { BorderPane root = new BorderPane(); Slider slider = new Slider(0, 200, 100); slider.setshowtickmarks(true); slider.setshowticklabels(true); slider.setmajortickunit(10); slider.setblockincrement(20); slider.minwidth(400); Binding and Properties Example Circle circle = new Circle( ); circle.setcenterx(250.0f); circle.setcentery(220.0f); circle.setfill(color.blueviolet); circle.setradius(50.0f); // not needed circle.radius().bind( slider.value( ) );...

13 Thinking about the GUI View Note: these messages are being sent by the Java system Model ~New~ Binding Properties ~Changed~ Event handlers Controller tells Model about users action

14 Line Example public void start(stage stage) { stage.settitle("binding Example"); AnchorPane root = new AnchorPane(); Scene scene = new Scene(root, 150, 150); System.out.println("Height: " + scene.height().doublevalue() ); System.out.println("Width: " + scene.width().doublevalue() ); Line line = new Line(0, 0, 150, 150 ); root.getchildren().add(line); } stage.setscene(scene); stage.show();

15 Line Example public void start(stage stage) { stage.settitle("binding Example"); AnchorPane root = new AnchorPane(); Scene scene = new Scene(root, 150, 150); System.out.println("Height: " + scene.height().getvalue() ); System.out.println("Width: " + scene.width().getvalue() ); Line line = new Line(0, 0, 150, 150 ); root.getchildren().add(line); } stage.setscene(scene); stage.show();

16 What We Want public void start(stage stage) { stage.settitle("binding Example"); AnchorPane root = new AnchorPane(); Scene scene = new Scene(root, 150, 150); System.out.println("Height: " + scene.height().getvalue() ); System.out.println("Width: " + scene.width().getvalue() ); Line line = new Line(0, 0, 150, 150 ); root.getchildren().add(line); stage.setscene(scene); stage.show(); } That will continue to be centered as the window changes sizes

17 First Step... public void start(stage stage) throws Exception { stage.settitle("binding Example"); AnchorPane root = new AnchorPane(); Scene scene = new Scene(root, 150, 150); Line line = new Line(0, 0, 150, 150 ); line.endx().bind( scene.width() ); line.starty().bind( scene.height().divide(2.0) ); line.endy().bind( scene.height().divide(2.0) ); root.getchildren().add(line); } stage.setscene(scene); stage.show();

18 First Step... Scene scene = new Scene(root, 150, 150); Line line = new Line(0, 0, 150, 150 ); line.endx().bind( scene.width()); line.starty().bind( scene.height().divide(2.0)); line.endy().bind( scene.height().divide(2.0));

19 // in start(stage stage) method Scene scene = new Scene(root, 150, 150); Second Step... Line line = new Line(0, 0, 150, 150 ); line.endx().bind( scene.width()); line.starty().bind( scene.height().divide(2.0)); line.endy().bind( scene.height().divide(2.0)); root.getchildren().add(line); line = new Line(0, 0, 0, 0 ); line.startx().bind( scene.width().divide(2.0) ); line.endx().bind( scene.width().divide(2.0) ); line.endy().bind( scene.height() ); root.getchildren().add(line); } stage.setscene(scene); stage.show();

20 // in start(stage stage) method Scene scene = new Scene(root, 150, 150); Second Step... Line line = new Line(0, 0, 150, 150 ); line.endx().bind( scene.width()); line.starty().bind( scene.height().divide(2.0)); line.endy().bind( scene.height().divide(2.0)); root.getchildren().add(line); line = new Line(0, 0, 0, 0 ); line.startx().bind( scene.width().divide(2.0) ); line.endx().bind( scene.width().divide(2.0) ); line.endy().bind( scene.height() ); root.getchildren().add(line); } stage.setscene(scene); stage.show();

21 Bindings Line line = new Line(0, 0, 150, 150 ); line.endx().bind( scene.width() ); line.starty().bind( scene.height().divide(2.0) ); line.endy().bind( scene.height().divide(2.0) ); JavaFX has SimpleFoo classes for: Boolean, Double, Integer, String, Object, List, Map, Set

22 Bindings Line line = new Line(0, 0, 150, 150 ); line.endx().bind( scene.width() ); line.starty().bind( scene.height().divide(2.0) ); line.endy().bind( scene.height().divide(2.0) ); JavaFX has SimpleFoo classes for: Boolean, Double, Integer, String, Object, List, Map, Set Each of the number types will have the following methods: add, subtract, divide, multipy, negate

23 Bindings Line line = new Line(0, 0, 150, 150 ); line.endx().bind( scene.width() ); line.starty().bind( scene.height().divide(2.0) ); line.endy().bind( scene.height().divide(2.0) ); JavaFX has SimpleFoo classes for: Boolean, Double, Integer, String, Object, List, Map, Set Each of the number types will have the following methods: add, subtract, divide, multipy, negate And the SimpleFoo classes will also have many other functions: isequalto, lessthan...

24 Bindings JavaFX has SimpleFoo classes for: Boolean, Double, Integer, String, Object, List, Map, Set Each of the number types will have the following methods: add, subtract, divide, multipy, negate And the SimpleFoo classes will also have many other functions: isequalto, lessthan... Also there is a Binding class that will have more static functions like: min, max, when

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