在JFrame中拥有背景图像时，将JButtons移动到左侧

Question

我是Java的新手并且正在开发一个项目。作为制作我的主菜单的测试，我一直在试验JFrame和powerrangers的图片。我的问题是我已经尝试了很多次，并花了很多时间试图让我的游戏和我的帮助按钮在我的窗口左侧。我已经尝试制作一个4格的网格并放入一个空标签，但它不会起作用。 这是我的代码：

package be.kdg.AngryTanksKlad;

import java.awt.*;
import java.awt.event.ActionEvent;
import java.io.IOException;
import java.net.URL;
import javax.imageio.ImageIO;
import javax.swing.*;

public class Main {
  public static void main(String[] args) throws IOException {
      final Image image = ImageIO.read(new URL("http://www.modernmom.com/sites/default/files/images/Power%2BRangers%2BPowerRangersMMPR.jpg"));
      final JFrame frame = new JFrame();
      frame.add(new ImagePanel(image));
      frame.setSize(800, 600);
      frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      frame.setVisible(true);
    }
  }




@SuppressWarnings("serial")
class ImagePanel extends JPanel {
  private Image image;
  private boolean tile;
  private JPanel menu = new JPanel(new FlowLayout(FlowLayout.LEFT));

  ImagePanel(Image image) {
    this.image = image;
    this.tile = false;
    final JButton play = new JButton("PLAY");
    final JButton help = new JButton("HELP");
    final JLabel empty = new JLabel();
  }

  menu.setLayout(new GridLayout(4,4));

  menu.add(empty);
  menu.add(play);
  menu.add(help);
  add(menu,BorderLayout.CENTER);
  menu.setOpaque(false);

  setVisible(true);
};

@Override
public void paintComponent(Graphics g) {
    super.paintComponent(g);
    if (tile) {
        int iw = image.getWidth(this);
        int ih = image.getHeight(this);
        if (iw > 0 && ih > 0) {
            for (int x = 0; x < getWidth(); x += iw) {
                for (int y = 0; y < getHeight(); y += ih) {
                    g.drawImage(image, x, y, iw, ih, this);
                }
            }
        }
    } else {
        g.drawImage(image, 0, 0, getWidth(), getHeight(), this);
    }
  }
}

Answer 1

这样的东西？

请参阅代码中的注释。

import java.awt.*;
import java.awt.image.*;
import java.awt.event.ActionEvent;
import java.io.IOException;
import java.net.URL;
import javax.imageio.ImageIO;
import javax.swing.*;
import javax.swing.border.*;

public class SillyNAmeForAMainClassGivenIHave100CalledMain {

public static void main(String[] args) throws IOException {
    final Image image = new BufferedImage(400,200,BufferedImage.TYPE_INT_RGB);
    final JFrame frame = new JFrame();
    frame.add(new ImagePanel(image));
    //frame.setSize(800, 600);
    frame.pack();
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setVisible(true);
}
}

@SuppressWarnings("serial")
class ImagePanel extends JPanel {
private Image image;
private boolean tile;
// add 5px spacing between buttons
private JPanel menu = new JPanel(new GridLayout(4,4,5,5));

ImagePanel(Image image) {
    super(new BorderLayout());  // default is FlowLayout!
    this.image = image;
    this.tile = false;
    final JButton play = new JButton("PLAY");
    final JButton help = new JButton("HELP");

    menu.add(play);
    menu.add(help);

    JPanel buttonConstrain = new JPanel(new FlowLayout());
    // pad the top of it..
    buttonConstrain.setBorder(new EmptyBorder(20,5,5,5));
    buttonConstrain.setOpaque(false);
    buttonConstrain.add(menu);
    // it won't help to use a BorderLayout contraint when the default is FlowLayout!
    // LINE_START = 'left' for left-to-right locales, right for the other
    add(buttonConstrain,BorderLayout.LINE_START);
    menu.setOpaque(false);

    setVisible(true);
}

@Override
public Dimension getPreferredSize() {
    Dimension d = null;
    if (image != null) {
        d = new Dimension(image.getWidth(this), image.getHeight(this));
    } else {
        d = new Dimension(600,400);
    }
    return d;
}

@Override
public void paintComponent(Graphics g) {
    super.paintComponent(g);
    if (tile) {
        int iw = image.getWidth(this);
        int ih = image.getHeight(this);
        if (iw > 0 && ih > 0) {
            for (int x = 0; x < getWidth(); x += iw) {
                for (int y = 0; y < getHeight(); y += ih) {
                    g.drawImage(image, x, y, iw, ih, this);
                }
            }
        }
    } else {
        g.drawImage(image, 0, 0, getWidth(), getHeight(), this);
    }
  }
}

Answer 2

  

“我的问题是我已经尝试了很多次，花了很多时间试图将我的游戏和我的帮助按钮放在窗口的左边。”

1. 将菜单换入另一个JPanel
2. 将主ImagePanel的布局设置为BorderLayout。
3. 将新JPanel添加到BorderLayout.WEST
的ImagePanel

4. setOpaque(false)到新JPanel

   JPanel panel = new JPanel();
   panel.setOpaque(false);
   panel.add(menu);
   setLayout(new BorderLayout());
   add(panel, BorderLayout.WEST);
   

---

工作正常



import java.awt.*;
import java.io.IOException;
import java.net.URL;
import javax.imageio.ImageIO;
import javax.swing.*;

public class Main {

    public static void main(String[] args) throws IOException {
        final Image image = ImageIO.read(new URL("http://www.modernmom.com/sites/default/files/images/Power%2BRangers%2BPowerRangersMMPR.jpg"));
        final JFrame frame = new JFrame();
        frame.add(new ImagePanel(image));
        frame.setSize(800, 600);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);
    }
}

@SuppressWarnings("serial")
class ImagePanel extends JPanel {

    private Image image;
    private boolean tile;
    private JPanel menu = new JPanel(new FlowLayout(FlowLayout.LEFT));

    ImagePanel(Image image) {
        this.image = image;
        this.tile = false;
        final JButton play = new JButton("PLAY");
        final JButton help = new JButton("HELP");
        final JLabel empty = new JLabel();


        menu.setLayout(
                new GridLayout(4, 4));

        menu.add(empty);

        menu.add(play);

        menu.add(help);

        JPanel panel = new JPanel();
        panel.setOpaque(false);
        panel.add(menu);
        setLayout(new BorderLayout());
        add(panel, BorderLayout.WEST);

        menu.setOpaque(false);

        setVisible(true);
    }

    @Override
    public void paintComponent(Graphics g) {
        super.paintComponent(g);
        if (tile) {
            int iw = image.getWidth(this);
            int ih = image.getHeight(this);
            if (iw > 0 && ih > 0) {
                for (int x = 0; x < getWidth(); x += iw) {
                    for (int y = 0; y < getHeight(); y += ih) {
                        g.drawImage(image, x, y, iw, ih, this);
                    }
                }
            }
        } else {
            g.drawImage(image, 0, 0, getWidth(), getHeight(), this);
        }
    }
}