How to Create a Custom Control in JavaFX - javafx

Question

Here I created my own control, with a canvas and ScrollBar. I didn't manage to correctly intercept the keyboard shortcuts or key pressed. When adding another component to the scene (here a TextField, commented), no keyboard events are received. Maybe I missed something about the focus?
Also, I had to add some --export to Gradle, to avoid some errors with the module.
plugins {
id 'application'
id 'org.openjfx.javafxplugin' version '0.0.8'
}
repositories {
mavenCentral()
}
javafx {
version = "15.0.1"
modules = [ 'javafx.controls', 'javafx.graphics' ]
}
run {
jvmArgs = ['--add-exports=javafx.controls/com.sun.javafx.scene.control.behavior=ALL-UNNAMED',
'--add-exports=javafx.controls/com.sun.javafx.scene.control.inputmap=ALL-UNNAMED']
}
mainClassName = 'com.wisecoders.textpane.CustomControlApp'
package com.wisecoders.textpane;
import com.sun.javafx.scene.control.behavior.BehaviorBase;
import com.sun.javafx.scene.control.inputmap.InputMap;
import com.sun.javafx.scene.control.inputmap.KeyBinding;
import javafx.application.Application;
import javafx.application.Platform;
import javafx.geometry.Orientation;
import javafx.scene.Scene;
import javafx.scene.canvas.Canvas;
import javafx.scene.canvas.GraphicsContext;
import javafx.scene.control.*;
import javafx.scene.input.Clipboard;
import javafx.scene.input.ClipboardContent;
import javafx.scene.input.KeyCode;
import javafx.scene.layout.BorderPane;
import javafx.scene.paint.Color;
import javafx.stage.Stage;
public class CustomControlApp extends Application {
private final BorderPane root = new BorderPane();
private final Scene scene = new Scene(root, 300, 250);
#Override
public void start(Stage stage) {
stage.setTitle("Sample Canvas");
root.setTop( new TextField());
MyControl control = new MyControl();
root.setCenter(control);
stage.setScene(scene);
stage.sizeToScene();
Platform.runLater( control::requestFocus );
stage.show();
}
public static void main(String[] args) {
launch(args);
}
class MyControl extends Control {
private final StringBuilder buffer = new StringBuilder();
public MyControl(){
setPrefSize(400, 400 );
setFocusTraversable(true);
setOnMouseClicked(ev-> requestFocus());
requestFocus();
setOnKeyTyped(ev-> { if ( !ev.isShortcutDown() ){
addTextToBuffer( ev.getCharacter() );
}});
}
public void addTextToBuffer( String str ){
buffer.append( str );
((MyControlSkin)getSkin()).paintCanvas();
}
public String getText(){ return buffer.toString(); }
#Override protected Skin<?> createDefaultSkin() {
return new MyControlSkin(this);
}
}
class MyControlSkin extends SkinBase<MyControl> {
final BorderPane borderPane = new BorderPane();
final ScrollBar rightScroll = new ScrollBar();
final Canvas canvas = new Canvas();
final MyControlBehavior behavior;
public MyControlSkin(MyControl control) {
super(control);
behavior = new MyControlBehavior( control );
rightScroll.setOrientation(Orientation.VERTICAL);
borderPane.setRight( rightScroll );
borderPane.setCenter(canvas);
canvas.setWidth( 150);
canvas.setHeight( 150 );
getChildren().add( borderPane );
paintCanvas();
}
public void paintCanvas(){
GraphicsContext gr = canvas.getGraphicsContext2D();
gr.clearRect( 0,0, canvas.getWidth(), canvas.getHeight());
gr.setFill( Color.BLACK);
gr.fillText( "Buff:" + getSkinnable().getText(), 30, 20 );
}
#Override
public void dispose() {
super.dispose();
behavior.dispose();
getChildren().removeAll();
}
}
class MyControlBehavior extends BehaviorBase<MyControl> {
final InputMap<MyControl> inputMap;
public MyControlBehavior(MyControl control) {
super(control);
this.inputMap = createInputMap();
addDefaultMapping( inputMap, new InputMap.KeyMapping(new KeyBinding(KeyCode.C).shortcut().ctrl(), e-> copy() ) );
}
public void copy(){
final Clipboard clipboard = Clipboard.getSystemClipboard();
final ClipboardContent content = new ClipboardContent();
content.putString( getNode().getText() );
clipboard.setContent(content);
}
#Override
public InputMap<MyControl> getInputMap() {
return inputMap;
}
}
}