JAVAFX UI CONTROLS AND MULTIMEDIA - Introduction to Java Programming: Comprehensive Version - page 667

58
59 HBox hBox = new HBox( 10 );
60 hBox.getChildren().addAll(btPlayPause,
61 new Label( "Select a nation: " ), cboNation);
62 hBox.setAlignment(Pos.CENTER);
63
64 // Create a pane to hold nodes
65 BorderPane pane = new BorderPane();
66 pane.setCenter(imageView);
67 pane.setBottom(hBox);
68
69 // Create a scene and place it in the stage
70 Scene scene = new Scene(pane, 350 , 270 );
71 primaryStage.setTitle( "FlagAnthem" ); // Set the stage title
72 primaryStage.setScene(scene); // Place the scene in the stage
73 primaryStage.show(); // Display the stage
74 }
75 }

The program loads the image and audio from the Internet (lines 29-33). A play/pause button is
created to control the playing of the audio (line 35). When the button is clicked, if the button's
current text is > (line 37), its text is changed to || (line 38) and the player is paused (line 39);
If the button's current text is || , it is changed to > (line 41) and the player is paused (line 42).
An image view is created to display a flag image (line 46). A combo box is created for
selecting a nation (line 47-49). When a new country name in the combo box is selected, the
current audio is stopped (line 53) and the newly selected nation's image is displayed (line 55)
and the new anthem is played (line 56).
JavaFX also provides the AudioClip class for creating auto clips. An AudioClip
object can be created using new AudioClip(URL) . An audio clip stores the audio in
memory. AudioClip is more efficient for playing a small audio clip in the program than
using MediaPlayer . AudioClip has the similar methods as in the MediaPlayer class.

16.43

✓ ✓

In Listing 16.15, which code sets the initial image icon and which code plays the
audio?

Check

Point

16.44

In Listing 16.15, what does the program do when a new nation is selected in the
combo box?

C HAPTER S UMMARY
1.

The abstract Labeled class is the base class for Label , Button , CheckBox , and
RadioButton . It defines properties alignment , contentDisplay , text , graphic ,
graphicTextGap , textFill , underline , and wrapText .

2.

The abstract ButtonBase class is the base class for Button , CheckBox , and
RadioButton . It defines the onAction property for specifying a handler for action events.

3.

The abstract TextInputContorl class is the base class for TextField and TextArea .
It defines the properties text and editable .

4. A TextField fires an action event when clicking the Enter key with the text field
focused. A TextArea is often used for editing a multiline text.

5. ComboBox<T> and ListView<T> are generic classes for storing elements of type T .
The elements in a combo box or a list view are stored in an observable list.