Question

所以我努力让这个工作起来。试图做一个小的调整应用程序。我想将按钮放在背景图像的适当调音栓的顶部（图像是吉他琴头）。但是，我无法弄清楚如何使用流布局来管理它。我可能只是愚蠢但是有人可以跟我说说这里发生什么事吗？

package guitartuner;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.text.*;
import java.awt.image.*;
import java.io.*;
import javax.imageio.*;


public class GuitarTuner extends JFrame{

private JFrame mainFrame;
private JLabel EJLabel, AJLabel, DJLabel, GJLabel, BJLabel, eJLabel, guitarJLabel,
        bassJLabel, loopJLabel;
private JPanel controlPanel;
private JButton EButton, AButton, DButton, GButton, BButton, eButton;

public class LoadImageApp extends Component{
    BufferedImage img;

    public void paint(Graphics g){
        g.drawImage(img, 0, 0, null);
    }

    public LoadImageApp(){
        try{
            img = ImageIO.read(new File("/Users/Yojimbo/NetBeansProjects/guitarTuner/src/guitartuner/headstock.jpg"));
        } catch (IOException e){    
        }
    }
    public Dimension getPreferredSize() {
        if (img == null) {
            return new Dimension(500,500);
        } else {
            return new Dimension(img.getWidth(null), img.getHeight(null));
        }
    }
}

public GuitarTuner(){
    createUserInterface();
}

public void createUserInterface(){



    JFrame f = new JFrame("Guitar Tuner");

    f.addWindowListener(new WindowAdapter(){
        public void windowClosing(WindowEvent e){
            System.exit(0);
        }
    });

    f.add(new LoadImageApp());
    f.setLayout(new FlowLayout());

    EButton = new JButton();
    EButton.setBounds(0, 0, 50, 10);
    EButton.setText("E");
    f.add(EButton);

    AButton = new JButton();
    AButton.setBounds(40, 40, 50, 10);
    AButton.setText("A");
    f.add(AButton);

    DButton = new JButton();
    DButton.setBounds(60, 60, 50, 10);
    DButton.setText("D");
    f.add(DButton);

    GButton = new JButton();
    GButton.setBounds(20, 100, 50, 10);
    GButton.setText("G");
    f.add(GButton);

    BButton = new JButton();
    BButton.setBounds(40, 100, 50, 10);
    BButton.setText("B");
    f.add(BButton);

    eButton = new JButton();
    eButton.setBounds(60, 100, 50, 10);
    eButton.setText("e");
    f.add(eButton);

    f.pack();
    f.setTitle("Aaron's Awesome Guitar Tuner");
    f.setSize (400, 575);
    f.setVisible(true);
}

public static void main(String[] args) {
    GuitarTuner application = new GuitarTuner();
    application.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}   
}

Answer 1

尝试使用GridBagLayout。花点时间阅读本文。如果您想将按钮放在所需的位置，这可能对您有所帮助。

https://docs.oracle.com/javase/tutorial/uiswing/layout/gridbag.html

Answer 2

您还可以在createUserInterface（） - Method

的开头添加这些行

编辑：如果您应该这样做，还必须删除LoadImageApp实例的f.add（...）。

public void createUserInterface() throws IOException {
    BufferedImage img = ImageIO.read(new File("/Users/Yojimbo/NetBeansProjects/guitarTuner/src/guitartuner/headstock.jpg"));
    JFrame f = new JFrame("Guitar Tuner");
    JPanel contentPane = new JPanel(){
        @Override
        protected void paintComponent(Graphics g) {
            super.paintComponent(g);
            g.drawImage(img, 0, 0, getWidth(), getHeight(), this);
        }
    };
    f.setContentPane(contentPane);
...

Answer 3

如果您希望组件相互重叠，则可以使用JLayeredPane。

请参阅：https://docs.oracle.com/javase/tutorial/uiswing/components/layeredpane.html

您可以将LoadImageApp放在一个图层中，将另一个JPanel放在FlowLayout中，其中包含您上面的图层中的按钮。

Answer 4

不要从组件中扩展LoadImageApp，将其从JPanel
覆盖paintComponent方法而不是paint。
将新图像面板的布局从其构造函数设置为FlowLayout。
不要设置框架布局，只需添加图像面板即可。并将所有按钮直接添加到图像面板。

以下是工作代码：

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.text.*;
import java.awt.image.*;
import java.io.*;
import javax.imageio.*;

public class GuitarTuner extends JFrame {

    private JFrame mainFrame;
    private JLabel EJLabel, AJLabel, DJLabel, GJLabel, BJLabel, eJLabel, guitarJLabel, bassJLabel, loopJLabel;
    private JPanel controlPanel;
    private JButton EButton, AButton, DButton, GButton, BButton, eButton;

    public class LoadImageApp extends JPanel {
        BufferedImage img;

        public void paintComponent(Graphics g) {
            g.drawImage(img, 0, 0, null);
        }

        public LoadImageApp() {
            super(new FlowLayout());
            try {
                img = ImageIO
                        .read(new File("/Users/Yojimbo/NetBeansProjects/guitarTuner/src/guitartuner/headstock.jpg"));
            } catch (IOException e) {
            }
        }

        public Dimension getPreferredSize() {
            if (img == null) {
                return new Dimension(500, 500);
            } else {
                return new Dimension(img.getWidth(null), img.getHeight(null));
            }
        }
    }

    public GuitarTuner() {
        createUserInterface();
    }

    public void createUserInterface() {

        JFrame f = new JFrame("Guitar Tuner");

        f.addWindowListener(new WindowAdapter() {
            public void windowClosing(WindowEvent e) {
                System.exit(0);
            }
        });

        LoadImageApp panel = new LoadImageApp();
        f.add(panel);

        EButton = new JButton();
        EButton.setBounds(0, 0, 50, 10);
        EButton.setText("E");
        panel.add(EButton);

        AButton = new JButton();
        AButton.setBounds(40, 40, 50, 10);
        AButton.setText("A");
        panel.add(AButton);

        DButton = new JButton();
        DButton.setBounds(60, 60, 50, 10);
        DButton.setText("D");
        panel.add(DButton);

        GButton = new JButton();
        GButton.setBounds(20, 100, 50, 10);
        GButton.setText("G");
        panel.add(GButton);

        BButton = new JButton();
        BButton.setBounds(40, 100, 50, 10);
        BButton.setText("B");
        panel.add(BButton);

        eButton = new JButton();
        eButton.setBounds(60, 100, 50, 10);
        eButton.setText("e");
        panel.add(eButton);

        f.pack();
        f.setTitle("Aaron's Awesome Guitar Tuner");
        f.setSize(400, 575);
        f.setVisible(true);
    }

    public static void main(String[] args) {
        GuitarTuner application = new GuitarTuner();
        application.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }
}

将按钮放在图像上？

4 个答案: