Question

j2me编程中drawImage函数使用无法显示图片

编译通过，没有抛出异常，代码如下：canvas类：package Graphics;import javax.microedition.lcdui.*;public class Mycanvas extends Canvas{private Image image;private int x =this.getWidth();private int y =this.getHeight();public Mycanvas(){try{image = Image.createImage("/L.png");}catch(Exception ex){System.out.println(ex);}}public void paint(Graphics g){//g.setColor(25,25,36);//g.fillRect(0, 0, x, y);g.drawImage(image, x,y , Graphics.LEFT|Graphics.TOP);System.out.println("hehe");}}主类package Graphics;import javax.microedition.midlet.MIDlet;import javax.microedition.midlet.MIDletStateChangeException;import javax.microedition.lcdui.*;public class test extends MIDlet {private Display display;private Mycanvas mycanvas;public test() {display = Display.getDisplay(this);mycanvas = new Mycanvas();}protected void startApp() throws MIDletStateChangeException {display.setCurrent(mycanvas);}protected void destroyApp(boolean arg0) throws MIDletStateChangeException {}protected void pauseApp() {}}

Answer 1

大哥，你把图片画到什么地方去了？
g.drawImage(image, x,y , Graphics.LEFT|Graphics.TOP);

试试：
g.drawImage(image, 0,0 , Graphics.LEFT|Graphics.TOP);

Answer 2

同上，但解释下原因。
x，y的取值是get width和height等于屏幕的最大宽高，直接画在了右下角看不见的地方
改成屏幕内的位置x=[0到getWidth之间]，y=[0到getHeight之间]都是屏幕内
才能
g.drawImage(image, x,y , Graphics.LEFT|Graphics.TOP);

画出来