Question

我的文字字段没有被添加到我的Jframe中，我希望这个文本字段可用，这样我就可以用它来改变绘画中矩形的高度。在actionperfomred我试图从该字段获取值，并希望它将重新绘制具有正确值的图像

import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;
import java.io.*;
import javax.imageio.*;
import javax.swing.*;
import java.net.*;
import java.sql.*;
import java.lang.Object;
import java.awt.Graphics;
import java.awt.Graphics2D;


public class Test extends JPanel implements ActionListener{

    JTextField textField;
    JFrame f=new JFrame();
    int x=77, y=441, w=23, h=10, entry;
    BufferedImage img=null;

    public void init(){
        JTextField textField=new JTextField(); 
        f.add(textField);
        textField.setBounds(10,10,40,30);
        textField.setVisible(true);
        textField.addActionListener(this);
    }

   // BufferedImage img;

   public static void main(String[] args) {
        BufferedImage img =new BufferedImage(100, 50,BufferedImage.TYPE_INT_ARGB); 
        //textField = new JTextField();
        JFrame f = new JFrame("Load Image Sample");

       /*textField=new JTextField();
        textField.addActionListener(this);
        f.add(textField);
        textField.setBounds(10,10,40,30);
        textField.setVisible(true);*/

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

        f.add(new Test());
        f.pack();
        f.setVisible(true);
    }


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

        Graphics2D i = img.createGraphics();
       Color myColor = Color.decode("#32004b");
       i.setColor(myColor);
       i.fillRect(x,y,w,h);

           // g.fillRect(10,10,10,10);
    }

    public Test() {

       try {
           img = ImageIO.read(new File("sales-goal.png"));
       } catch (IOException e) {}



                //77,441,23,10
    }

    public Dimension getPreferredSize() {
        if (img == null) {
             return new Dimension(100,100);
        } else {
           //return new Dimension(img.getWidth(null), img.getHeight(null));
            return new Dimension(300,600);
       }
    }


    public void actionPerformed(ActionEvent e) {

        Graphics g= getGraphics();


               if (e.getSource() == textField) {
                   entry= Integer.parseInt(textField.getText());
                   g.drawString("Test",50,50);

                   entry=h;

                }

    }
}

Answer 1

我认为这是因为你从不调用方法init

Answer 2

调用你的init方法，你会没事的

不将TextField添加到jFrame

2 个答案: