StackPane setBackground

Question

下面是我的代码：

import javafx.application.Application;
import javafx.geometry.Insets;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.layout.Background;
import javafx.scene.layout.BackgroundFill;
import javafx.scene.layout.CornerRadii;
import javafx.scene.layout.StackPane;
import javafx.scene.paint.Color;
import javafx.stage.Stage;

public class NotesApplication extends Application {
    @Override
    public void start(Stage stage) {
        StackPane root = new StackPane();
        root.setPrefSize(700,700);

        StackPane leftPane = new StackPane();
        leftPane.setPrefSize(100, 700);
        Button button = new Button("Button 1");
        leftPane.setBackground(new Background(new BackgroundFill(Color.YELLOW, CornerRadii.EMPTY, Insets.EMPTY)));
        leftPane.getChildren().add(button);
        leftPane.setAlignment(Pos.CENTER_LEFT);

        StackPane rightPane = new StackPane();
        rightPane.setPrefSize(200,700);
        Button button1 = new Button("Button 2");
        rightPane.getChildren().add(button1);
        rightPane.setAlignment(Pos.CENTER_RIGHT);

        root.getChildren().addAll(leftPane, rightPane);

        Scene scene = new Scene(root);
        stage.setScene(scene);
        stage.show();
    }

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

如您所见，我有一个带有根StackPane的类，在根StackPane中还有另外两个StackPanes(leftPane和rightPane)。我想只将leftPane的背景颜色设置为黄色，但结果是整个窗口的背景都是黄色的，我做错了什么？

提前谢谢。

Answer 1

如果您没有特殊的理由使用StackPane作为根目录，那么可以使用AnchorPane。你可以为你的左侧和右侧StackPanes设置3个侧边锚点，并将你的stackpanes的宽度与你的根宽度绑定在一起，所以如果你调整你的窗口大小，你的stackpanes将会适应它

import javafx.application.Application;
import javafx.geometry.Insets;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.layout.*;
import javafx.scene.paint.Color;
import javafx.stage.Stage;

public class NotesApplication extends Application {
    @Override
    public void start(Stage stage) {
        AnchorPane root = new AnchorPane(); // Changed stackpane to anchor pane
        root.setPrefSize(700,700);

        StackPane leftPane = new StackPane();
        leftPane.minWidthProperty().bind(root.widthProperty().divide(2)); // Binding leftPane's width with the half of your root

        Button button = new Button("Button 1");
        leftPane.setBackground(new Background(new BackgroundFill(Color.YELLOW, CornerRadii.EMPTY, Insets.EMPTY)));
        leftPane.getChildren().add(button);
        leftPane.setAlignment(Pos.CENTER_LEFT);

        StackPane rightPane = new StackPane();
        rightPane.minWidthProperty().bind(root.widthProperty().divide(2)); // Binding rightPane's width with the half of your root

        Button button1 = new Button("Button 2");
        rightPane.getChildren().add(button1);
        rightPane.setAlignment(Pos.CENTER_RIGHT);
        rightPane.setBackground(new Background(new BackgroundFill(Color.RED, CornerRadii.EMPTY, Insets.EMPTY)));

        root.getChildren().addAll(leftPane, rightPane);

        // Setting the anchors 
        root.setLeftAnchor(leftPane, 0.0);
        root.setTopAnchor(leftPane, 0.0);
        root.setBottomAnchor(leftPane, 0.0);

        root.setRightAnchor(rightPane, 0.0);
        root.setTopAnchor(rightPane, 0.0);
        root.setBottomAnchor(rightPane, 0.0);


        Scene scene = new Scene(root);
        stage.setScene(scene);
        stage.show();
    }

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