JavaFx 可拖拽滚动面板

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运行效果

通过鼠标拖拽面板的方式来实现滚动条滚动效果。

代码案例

import javafx.application.Application;
import javafx.geometry.Insets;
import javafx.scene.Scene;
import javafx.scene.control.ScrollPane;
import javafx.scene.control.Tooltip;
import javafx.scene.input.MouseEvent;
import javafx.scene.layout.Border;
import javafx.scene.layout.BorderStroke;
import javafx.scene.layout.BorderStrokeStyle;
import javafx.scene.layout.BorderWidths;
import javafx.scene.layout.CornerRadii;
import javafx.scene.layout.Pane;
import javafx.scene.layout.Region;
import javafx.scene.paint.Color;
import javafx.stage.Stage;
import javafx.util.Duration;

public class DraggablePane extends Application {

	@Override
	public void start(Stage stage) throws Exception {
		Tooltip tip = new Tooltip("鼠标左键拖拽可移动面板");
		tip.setShowDelay(new Duration(20));

		Pane root = new Pane();
		Tooltip.install(root, tip);
		root.setBorder(new Border(
				new BorderStroke(Color.RED, BorderStrokeStyle.DASHED, new CornerRadii(20), new BorderWidths(1.0))));
		root.setPrefSize(800, 600);

		DragScrollPane scrollPane = new DragScrollPane();
		scrollPane.setPadding(new Insets(10));
		scrollPane.setDragContent(root);

		Scene scene = new Scene(scrollPane, 500, 300);
		stage.setTitle("DraggablePane");
		stage.setScene(scene);
		stage.show();

	}

	public static void main(String[] args) {
		launch(args);
	}

	/**
	 * 可拖拽滚动面板
	 */
	public class DragScrollPane extends ScrollPane {

		/** 是否正在拖拽 */
		private boolean isDrag;
		private double startX;
		private double startY;
		private double startHvalue;
		private double startVvalue;

		private Region content;

		public DragScrollPane() {
			this(null);
		}

		public DragScrollPane(Region content) {
			setDragContent(content);
		}

		public void setDragContent(Region content) {
			this.content = content;
			setContent(content);
			addDragEvent();
		}

		private void addDragEvent() {
			if (content != null) {
				content.addEventHandler(MouseEvent.MOUSE_PRESSED, event -> {
					startX = event.getSceneX();
					startY = event.getSceneY();
					startHvalue = getHvalue();
					startVvalue = getVvalue();
					isDrag = false;
				});

				content.addEventHandler(MouseEvent.MOUSE_DRAGGED, event -> {
					if (event.isPrimaryButtonDown()) {
						double moveX = startX - event.getSceneX();
						double moveY = startY - event.getSceneY();
						setHvalue(startHvalue + moveX / (content.getWidth() - getWidth()));
						setVvalue(startVvalue + moveY / (content.getHeight() - getHeight()));
						isDrag = true;
					}
				});
			}
		}

		public boolean isDrag() {
			return isDrag;
		}
	}
}