java - 在JFrame上放置JPanels不正确

我编写了一个程序来使用我的作业使用swing / awt框架来组成GUI。到目前为止，我能够使各个部分协同工作，但是当我将它们全部放入JFrame时，它们并没有按预期的那样推出。

我最近开始研究Java GUI框架，不确定我的代码中缺少什么。如何使它正常工作？

我还附上了我得到的输出的屏幕截图（见底部）。

public class MainFrame extends JFrame {

    public MainFrame() {
    addComponentsToPane(this.getContentPane());
    }

    private void addComponentsToPane(Container pane) {

        // Set layout
        GridBagConstraints gbc = new GridBagConstraints();
        this.setTitle("Test tool");
        this.setSize(600, 650);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        this.setLayout(new GridLayout(2, 1));

        // Add video JComponent
        mMainPanel = new MainPanel();
        pane.add(mMainPanel, 0);

        // Add conference screen panel
        mFeedPanel = new FeedPanel();
        pane.add(mFeedPanel, 1);

        // Add a button panel
        mButtonPanel = new ButtonPanel();
        pane.add(mButtonPanel, 2);

        this.setResizable(true);
        this.setVisible(true);
        this.pack();
    }
}

// In actual output, there is 1 screen in this panel.
// mScreen1 is derived from JComponent object.
public class MainPanel() extends JPanel {

    public MainPanel() {
    addMainPanelComponents();
    }

    private void addMainPanelComponents() {
        this.setSize(352, 240);
        setBackground(Color.yellow);
        setLayout(new GridLayout(1, 2));
        add(mScreen);
        setVisible(true);
    }
}

// In actual output, there are 3 screens in this panel. I have shown code for 1 screen only
// mScreen1 is derived from JComponent object.
public class FeedPanel extends JPanel {

    public FeedPanel() {
    addFeedPanelComponents();
    }

    private void addFeedPanelComponents() {

        String img1 = "images/screen1.png";

        setSize(352, 150);
        setBackground(Color.yellow);
        setLayout(new GridLayout(1, 3));

        Image image1 = ImageIO.read(new File(img1));
        mScreen1.setImage(image1);
        add(mScreen1);
        setVisible(true);
    }
}

public class ButtonPanel extends JPanel {

    public ButtonPanel() {
    addButtonPanelComponents();
    }

    private void addButtonPanelComponents() {

        this.setSize(352, 150);
        this.setBackground(Color.yellow);
        this.setLayout(new GridLayout(1,
                                      5));

        // Add Button to panel
        mStartButton = new JButton("Start");
        this.add(mStartButton);
        mStartButton.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent ae) {
                StartButtonActionListener(ae);
            }
        });

        mStopButton = new JButton("Stop");
        this.add(mStopButton);
        mStopButton.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent ae) {
                StopButtonActionListener(ae);
            }
        });
        setVisible(true);
    }
}

这是运行代码时的默认值。

 

这是在手动调整框架大小之后。

最佳答案

BorderLayout，GirdLayout和BoxLayout的组合可以为您完成此操作（实际上，这不是唯一的选择）。

这是代码：

import java.awt.BorderLayout;
import java.awt.GridLayout;

import javax.swing.Box;
import javax.swing.BoxLayout;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;

public class GridLayoutTest {
    public void createUI(){
        JFrame frame = new JFrame();

        JPanel topPanel = new TopPanel();
        JPanel buttomPanel = new ButtomPanel();


        JPanel mainPanel = new JPanel();
        mainPanel.setLayout(new BorderLayout());
        mainPanel.add(topPanel,BorderLayout.CENTER);
        mainPanel.add(buttomPanel,BorderLayout.SOUTH);
        frame.add(mainPanel,BorderLayout.CENTER);
        frame.pack();
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        GridLayoutTest test = new GridLayoutTest();
        test.createUI();
    }

    @SuppressWarnings("serial")
    class TopPanel extends JPanel{
        public TopPanel(){
            setLayout(new GridLayout(2, 3));
            ImageIcon icon = new ImageIcon("capture.png");
            JLabel label1 = new JLabel(icon);
            label1.setVisible(false);
            JLabel label2 = new JLabel(icon);
            JLabel label3 = new JLabel(icon);
            label3.setVisible(false);
            JLabel label4 = new JLabel(icon);
            JLabel label5 = new JLabel(icon);
            JLabel label6 = new JLabel(icon);
            add(label1);
            add(label2);
            add(label3);
            add(label4);
            add(label5);
            add(label6);
        }
    }

    @SuppressWarnings("serial")
    class ButtomPanel extends JPanel{
        public ButtomPanel(){
            JButton startButton = new JButton("start");
            JButton stopButton = new JButton("stop");
            JButton recordButton = new JButton("record");

            setLayout(new BoxLayout(this, BoxLayout.X_AXIS));
            add(Box.createHorizontalGlue());
            add(startButton);
            add(Box.createHorizontalStrut(10));
            add(stopButton);
            add(Box.createHorizontalStrut(10));
            add(recordButton);
            add(Box.createHorizontalGlue());
        }
    }
}

BoxLayout太好了，它还提供了空白区域并帮助您将组件居中。

    setLayout(new BoxLayout(this, BoxLayout.X_AXIS));
    add(Box.createHorizontalGlue());
    add(startButton);
    add(Box.createHorizontalStrut(10));
    add(stopButton);
    add(Box.createHorizontalStrut(10));
    add(recordButton);
    add(Box.createHorizontalGlue());

在第一个组件之前和最后一个组件之后添加胶水将帮助您使组件也居中，并添加支杆可以帮助您提供所需的空白。您可以参考https://stackoverflow.com/a/22525005/3378204以获得更多详细信息。

效果如下：







BoxLayout不会影响组件的大小。希望它能对您有所帮助。