canvasdemo.java

jBuilderX无线应用开发源代码

import javax.microedition.midlet.MIDlet;
import javax.microedition.lcdui.*;

public class CanvasDemo extends MIDlet
{
	private Display display;

	public CanvasDemo(){
	}

	public void startApp(){
		display=Display.getDisplay(this);
		//创建MyCanvas对象，并将其设置为当前要显示的屏幕
		MyCanvas canvas = new MyCanvas();
		display.setCurrent(canvas);
	}

	public void pauseApp(){
	}

	public void destroyApp(boolean unconditional){
	}
}
//MyCanvas继承了Canvas类
class MyCanvas extends Canvas
{
	//绘图方法
	protected void paint(Graphics g){
		//将绘图颜色设置为白色
		g.setColor(255,255,255);
		//用当前绘图颜色填充整个屏幕
		g.fillRect(0,0,getWidth(),getHeight());
		//将绘图颜色设置为红色
		g.setColor(255,0,0);
		//用当前绘图颜色绘制字符串"Hello World"
		g.drawString("Hello World",10,10,Graphics.LEFT|Graphics.TOP);
	}
};