[英]Paint new things on JPanel
好的,所以我有一個JPanel重寫了paintComponent方法。
很簡單,看起來像這樣:
public class Panel1 extends JPanel {
public void paintComponent (Graphics g) {
super.paintComponent (g);
g.fillOval (0, 0, getWidth (), getHeight ());
}
}
現在,我將此JPanel作為屬性添加到另一個JPanel類,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);
}
}
我想要的是將Panel2繪畫成與Panel1完全一樣(無需對其進行硬編碼),並可能添加其他內容(例如三角形或某物,我不知道)。
這有可能嗎? 我調查了一下,但沒有找到任何方法。 在此先感謝您的幫助!!
MAIN,以幫助:
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);
}
}
編輯:以防萬一,我不想繼承。 這就是為什么我將其添加為屬性的原因,但是如果還有其他方法,請讓我現在進行。
您可以嘗試將Panel1
paintComponent
公開,然后在Panel2
paintComponent
中調用它:
protected void paintComponent (Graphics g) {
panel1.paintComponent(g);
}
您還可以在Panel1
類中創建一個方法來為您處理繪畫
public void yourPainting(Graphics g){
//whatever you want to paint
}
然后在Panel1
和Panel2
的paintComponent
方法中調用此方法
它不按問題中的方式工作的原因是Panel1
的大小為0x0。 要獲得合理的尺寸,請從getPreferredSize()
返回尺寸,然后將面板尺寸設置為首選尺寸。
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);
}
}
我相信應該可以
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.