3
我試圖向現有的JPanel添加/繪製單個Graphics對象。我生成了10個隨機大小的初始圖形對象並放置在面板中,但希望一次添加其他繪製對象,隨機大小和初始位置10.試圖在JPanel中添加一個動態定位的圖像按鈕單擊
目前,AddNewDrawItem類不會呈現新的圖形對象。
感謝您的意見。
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Random;
public class Painter{
private DrawingPanel dp = new DrawingPanel();
//constructor
public Painter(){
buildGUI();
}
private void buildGUI(){
JFrame frame = new JFrame();
frame.setLayout(new BorderLayout());
frame.setTitle("Paint drawing demonstration");
JPanel headerPanel = new JPanel();
headerPanel.add(new JLabel("The drawing panel is below"));
JButton addNew = new JButton("Add New Graphic");
addNew.addActionListener(new addNewClickHandler());
headerPanel.add(addNew);
frame.add(BorderLayout.NORTH,headerPanel);
frame.add(BorderLayout.SOUTH,this.dp);
frame.pack();
frame.setVisible(true);
}
class DrawingPanel extends JPanel {
public void paintComponent(Graphics g) {
super.paintComponent(g);
this.setBackground(Color.white);
int x, posx, posy, width, height;
for(x=0;x<=10;x++){
//even number differentiation
if(x % 2 == 0){
g.setColor(Color.red);
}else{
g.setColor(Color.blue);
}
Random rand = new Random();
posx = rand.nextInt(300);
posy = rand.nextInt(300);
width = rand.nextInt(40);
height = rand.nextInt(40);
//System.out.println("the ran x pos is: " + posx);
g.fillRect(posx, posy, width, height);
}//end for
}//end paintComponent
public Dimension getPreferredSize() {
return new Dimension(400,400);
}
}// end DrawingPanel
private class addNewClickHandler implements ActionListener{
public void actionPerformed(ActionEvent e){
System.out.print("in addNew_click_handler click handler");//trace debug
AddNewDrawItem newItem = new AddNewDrawItem();
newItem.repaint();
System.out.print("after repaint() in addNew_click_handler click handler");//trace debug
}
}
class AddNewDrawItem extends JPanel {
public void paintComponent(Graphics g) {
super.paintComponent(g);
this.setBackground(Color.white);
int posx, posy, width, height;
Random rand = new Random();
posx = rand.nextInt(300);
posy = rand.nextInt(300);
width = rand.nextInt(40);
height = rand.nextInt(40);
g.setColor(Color.cyan);
g.fillRect(posx, posy, width, height);
}//end paintComponent
}//end AddNewDrawItem
public static void main(String args[]){
new Painter();
}
}//end class Painter
+1雖然我會建議界面,列表'。 –
trashgod
謝謝,我想我明白了氣墊船的說法。我會給更新一個鏡頭,並在完成後發佈重做代碼。 – jamesTheProgrammer