设置 JFrame 大小后 JPanel 大小不会更新

Question

所以我在让它工作时遇到了一些困难。我正在创建一个 JFrame 并使用 BorderLayout.CENTER 添加一个 JPanel 到它的中心。就创建它而言，一切都非常有效，但每当我现在通过执行以下操作调整 window 的大小时：window.setSize(new Dimension(600,600));，内部的 JPanel 不会自动更新以拉伸到 window。我正在尝试从 JPanel 的大小获取信息，但由于 JPanel 的大小不会在 window 更改后立即更新，因此 JPanel 的大小保持不变。

这是我的代码（以及我在说什么）：（updateMinHeightAndWidth() 和 getMinHeightAndWidth() 几乎相同，但需要分开）

(listenLabel)

public class listenPanel extends JPanel {

    public void redoWindowSetup() {
        window.setSize(new Dimension(600,600));
        window.repaint(); //Where image is shown
        JPanel tempJPanel;
        listenButton listenButton;
        for (temporaryIncrimentVariable = 0; temporaryIncrimentVariable < list.getRows() * list.getColumns(); temporaryIncrimentVariable++) {
            tempJPanel = new JPanel();
            tempJPanel.setLayout(new BorderLayout());
            tempJPanel.setOpaque(false);
            listenButton = new listenButton();
            tempJPanel.add(listenButton, BorderLayout.CENTER);
            listenLabel timerLabel = new listenLabel();
            tempJPanel.add(timerLabel, BorderLayout.NORTH);
            centerPanel.add(tempJPanel);
        }
        window.add(centerPanel,BorderLayout.CENTER);
        int[] updatedMinHeightAndWidth = updateMinHeightAndWidth();
        window.setMinimumSize(new Dimension(updatedMinHeightAndWidth[1], updatedMinHeightAndWidth[0]));
        window.setVisible(true);
        window.repaint();
    }

    private int[] updateMinHeightAndWidth() {
        int tempVerticalSize;
        window.pack();
        window.setVisible(true);
        int upperBound = 40000;
        int lowerBound = 0;
        try {
            window.setSize(new Dimension(40, (upperBound + lowerBound) / 2)); //Set window size to halfway in the middle
            Thread.sleep(200);
        } catch (InterruptedException e) {

        }
        while (centerPanel.getSize().height != (MAX_HEIGHT * list.getRows()) && ((lowerBound + upperBound) / 2) != lowerBound) {
            centerPanel.repaint();
            System.out.println(centerPanel.getSize().height);
            if (centerPanel.getSize().height > (MAX_HEIGHT * list.getRows())) {
                upperBound = (upperBound + lowerBound) / 2;
            } else {
                lowerBound = (upperBound + lowerBound) / 2;
            }
            try {
                window.setSize(new Dimension(40, (upperBound + lowerBound) / 2)); //Set window size to halfway in the middle
                Thread.sleep(200);
            } catch (InterruptedException e) {

            }
        }

        tempVerticalSize = upperBound;

        upperBound = 40000;
        lowerBound = 0;
        try {
            window.setSize(new Dimension((upperBound + lowerBound) / 2, 40)); //Set window size to halfway in the middle
            Thread.sleep(200);
        } catch (InterruptedException e) {

        }
        while (centerPanel.getSize().width != (MAX_WIDTH * list.getColumns()) && ((lowerBound + upperBound) / 2) != lowerBound) {
            if (centerPanel.getSize().width > (MAX_WIDTH * list.getColumns())) {
                upperBound = (upperBound + lowerBound) / 2;
            } else {
                lowerBound = (upperBound + lowerBound) / 2;
            }
            try {
                window.setSize(new Dimension((upperBound + lowerBound) / 2, 40)); //Set window size to halfway in the middle
                Thread.sleep(200);
            } catch (InterruptedException e) {

            }
        }

        return new int[]{tempVerticalSize, upperBound};
    }
}

还有我的构造函数

public TestingCenterWindow() {
    list = new ComputerList();
    window = new JFrame();
    window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    window.setResizable(true);
    window.setSize(500, 500);
    window.setTitle("Testing Center Computers");
    window.setLayout(new BorderLayout());

    centerPanel = new listenPanel();
    centerPanel.setBackground(Color.BLUE);
    centerPanel.setLayout(new GridLayout(list.getRows(), list.getColumns()));

    JPanel tempJPanel;
    listenButton listenButton;
    for (temporaryIncrimentVariable = 0; temporaryIncrimentVariable < list.getRows() * list.getColumns(); temporaryIncrimentVariable++) {
        tempJPanel = new JPanel();
        tempJPanel.setLayout(new BorderLayout());
        tempJPanel.setOpaque(false);
        listenButton = new listenButton();
        tempJPanel.add(listenButton, BorderLayout.CENTER);
        listenLabel timerLabel = new listenLabel();
        tempJPanel.add(timerLabel, BorderLayout.NORTH);
        centerPanel.add(tempJPanel);
    }

    window.add(centerPanel, BorderLayout.CENTER);
    window.setJMenuBar(computerMenuBar);

    int[] minHeightAndWidth = getMinHeightAndWidth();
    window.setMinimumSize(new Dimension(minHeightAndWidth[1], minHeightAndWidth[0]));

    window.setVisible(true);
}

private int[] getMinHeightAndWidth() {
    int tempVerticalSize;
    window.pack();
    window.setVisible(false);
    int upperBound = 40000;
    int lowerBound = 0;
    try {
        window.setSize(new Dimension(40, (upperBound + lowerBound) / 2)); //Set window size to halfway in the middle
        Thread.sleep(200);
    } catch (InterruptedException e) {

    }
    while (centerPanel.getSize().height != (MAX_HEIGHT * list.getRows()) && ((lowerBound + upperBound) / 2) != lowerBound) {
        if (centerPanel.getSize().height > (MAX_HEIGHT * list.getRows())) {
            upperBound = (upperBound + lowerBound) / 2;
        } else {
            lowerBound = (upperBound + lowerBound) / 2;
        }
        try {
            window.setSize(new Dimension(40, (upperBound + lowerBound) / 2)); //Set window size to halfway in the middle
            Thread.sleep(200);
        } catch (InterruptedException e) {

        }
    }

    tempVerticalSize = upperBound;

    upperBound = 40000;
    lowerBound = 0;
    try {
        window.setSize(new Dimension((upperBound + lowerBound) / 2, 40)); //Set window size to halfway in the middle
        Thread.sleep(200);
    } catch (InterruptedException e) {

    }
    while (centerPanel.getSize().width != (MAX_WIDTH * list.getColumns()) && ((lowerBound + upperBound) / 2) != lowerBound) {
        if (centerPanel.getSize().width > (MAX_WIDTH * list.getColumns())) {
            upperBound = (upperBound + lowerBound) / 2;
        } else {
            lowerBound = (upperBound + lowerBound) / 2;
        }
        try {
            window.setSize(new Dimension((upperBound + lowerBound) / 2, 40)); //Set window size to halfway in the middle
            Thread.sleep(200);
        } catch (InterruptedException e) {

        }
    }

    return new int[]{tempVerticalSize, upperBound};
}

因此，每当我在首次创建 window 时尝试获得最小尺寸时，它都可以正常工作。当 window 改变大小时，JPanel 也会改变大小，因此它可以在 window 改变后获取 JPanel 的大小。每当我为我的 listenLabel 执行完全相同的代码时，在调用 redoWindowSetup() 之后，window 会这样做：

http://i.stack.imgur.com/BG6x3.png

蓝色区域通常会拉伸，但现在不会拉伸，因此随着 window 更改大小，JPanel 的大小保持在一个值。我已经尝试在 window 和 centerPanel 上使用 paintAll 和 repaint，但我似乎无法让它工作。

Answer 1

我发现了如何解决这个问题。这仅仅是因为在设置 window 大小后我需要一个 JFrame.revalidate() 语句。这手动强制面板尺寸更新。

设置 JFrame 大小后 JPanel 大小不会更新

JPanel size wont update after setting JFrame size

java

swing

jpanel

jframe