[英]Paint new things on JPanel
好的,所以我有一个JPanel重写了paintComponent方法。
很简单,看起来像这样:
public class Panel1 extends JPanel {
public void paintComponent (Graphics g) {
super.paintComponent (g);
g.fillOval (0, 0, getWidth (), getHeight ());
}
}
现在,我将此JPanel作为属性添加到另一个JPanel类,例如:
public class Panel2 extends JPanel {
Panel1 panel;
public Panel2 (Panel1 panel) {
this.panel = panel;
}
protected void paintComponent (Graphics g) {
super.paintComponent (g);
panel.paint (g); //This isn't working.
// panel.paintComponent (g); //Tried this too
g.drawOval (100, 100, getWidth () - 200, getHeight () - 200);
}
}
我想要的是将Panel2绘画成与Panel1完全一样(无需对其进行硬编码),并可能添加其他内容(例如三角形或某物,我不知道)。
这有可能吗? 我调查了一下,但没有找到任何方法。 在此先感谢您的帮助!!
MAIN,以帮助:
public class Main {
public static void main (String[] args) {
JFrame frame = new JFrame ();
frame.setSize (500, 500);
frame.add (new Panel2 (new Panel1 ()));
frame.setVisible (true);
}
}
编辑:以防万一,我不想继承。 这就是为什么我将其添加为属性的原因,但是如果还有其他方法,请让我现在进行。
您可以尝试将Panel1
paintComponent
公开,然后在Panel2
paintComponent
中调用它:
protected void paintComponent (Graphics g) {
panel1.paintComponent(g);
}
您还可以在Panel1
类中创建一个方法来为您处理绘画
public void yourPainting(Graphics g){
//whatever you want to paint
}
然后在Panel1
和Panel2
的paintComponent
方法中调用此方法
它不按问题中的方式工作的原因是Panel1
的大小为0x0。 要获得合理的尺寸,请从getPreferredSize()
返回尺寸,然后将面板尺寸设置为首选尺寸。
import java.awt.*;
import javax.swing.*;
public class PaintUnrealized {
public static void main(String[] args) {
Runnable r = new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (Exception useDefault) {
}
JFrame f = new JFrame("Paint Unrealized Component");
f.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
f.setLocationByPlatform(true);
f.setContentPane(new Panel2(new Panel1()));
f.pack();
f.setMinimumSize(f.getSize());
f.setVisible(true);
}
};
SwingUtilities.invokeLater(r);
}
}
class Panel1 extends JPanel {
public Panel1() {
setBackground(Color.RED);
setSize(getPreferredSize());
}
public void paintComponent(Graphics g) {
super.paintComponent(g);
g.fillOval(0, 0, getWidth(), getHeight());
}
@Override
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}
}
class Panel2 extends JPanel {
Panel1 panel;
public Panel2(Panel1 panel) {
this.panel = panel;
setBackground(Color.YELLOW);
}
protected void paintComponent(Graphics g) {
super.paintComponent(g);
panel.paintComponent(g); // This works
int pad = 25;
g.drawOval(pad, pad, getWidth()-(2*pad), getHeight()-(2*pad));
}
@Override
public Dimension getPreferredSize() {
return new Dimension(500, 300);
}
}
public class Panel2 extends JPanel {
private Panel1 panel1;
public Panel2 (Panel1 panel) {
this.panel1 = panel;
}
protected void paintComponent (Graphics g) {
panel1.paint(g);
}
}
我相信应该可以
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.