java - 在 JavaFX 2 中将工具栏按钮设置为方形且大小相同

Question

在下面的代码中，我有一个工具栏，并向其中添加了各种大小的按钮。我希望按钮是方形的并且大小相同。因此，基本上找到所有按钮中最长的宽度或高度，并将所有其他按钮的宽度和高度设置为该尺寸。然而，按钮可以改变大小，所以我认为我需要一个绑定(bind)。我不太明白 - 有人知道该怎么做吗？

import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.ToolBar;
import javafx.scene.layout.BorderPane;
import javafx.stage.Stage;

public class ToolBarButtonTest extends Application {
    @Override
    public void start(Stage stage) throws Exception {
        BorderPane borderPane = new BorderPane();
        Scene scene = new Scene(borderPane, 500, 500);

        ToolBar toolBar = new ToolBar();

        Button button1 = new Button("s");
        Button button2 = new Button("ss");
        Button button3 = new Button("sss");

        toolBar.getItems().addAll(button1, button2, button3);

        borderPane.setTop(toolBar);

        stage.setScene(scene);
        stage.show();
    }

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

谢谢，尼克。

Answer 1

给你。此示例将使用 CSS 将按钮形状变成正方形，并安装验证监听器来跟踪按钮的布局更改并相应地更新宽度。

public class SquareButtons extends Application {
@Override
  public void start(final Stage stage) throws Exception {
    /* Assume these are your toolbar elements */
    final Button[] buttons = new Button[]{
            new Button("Short"),
            new Button("Slightly longer"),
            new Button("Very very very long button")
    };

    /* This would, of course, belong in a style sheet - it turns the buttons square */
    for (Button b : buttons)
        b.setStyle("-fx-background-radius: 0");

    /* This will set the pref width/height of all your buttons to the maximum of the pref width/height of the larget one */
    final InvalidationListener listener = new InvalidationListener() {
        public void invalidated(final Observable observable) {
            double size = 0;
            for (Button b : buttons) {
                size = Math.max(size, b.prefWidth(Integer.MAX_VALUE));
                size = Math.max(size, b.prefHeight(Integer.MAX_VALUE));
            }

            for (Button b : buttons) {
                b.setPrefWidth(size);
                b.setPrefHeight(size);
            }
        }
    };

    for (Button b : buttons)
        b.widthProperty().addListener(listener);

    final ToolBar toolbar = new ToolBar();
    toolbar.getItems().addAll(buttons);

    final Scene scene = new Scene(toolbar);
    stage.setScene(scene);
    stage.setWidth(800);
    stage.setHeight(200);
    stage.show();
  }

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

更新:没有足够彻底地阅读问题，请参阅评论。