Question

我试图在1秒后更改图像以进行图像查看。但它不会在屏幕上显示任何图像。以下是code.please help.thank you。

代码 -

public class Shapes extends Activity {

     Timer timer = new Timer();
     int flag;
     String images[]={};
     ImageView iv;
     static int v[]={R.drawable.round,R.drawable.rectangle};
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        setContentView(R.layout.shapes);
         iv=(ImageView) findViewById(R.id.imageView1);

         timer.schedule(new TimerTask() {

             public void run() {
                 runOnUiThread(new Runnable() {

                     public void run() {

                        if (flag > 1) {
                             timer.cancel();
                             timer = null;
                         } else
                             iv.setImageResource(v[flag++]);

                     }
                 });

             }
         }, System.currentTimeMillis(), 1000);

    }
}

如何检查资源图像并进行更改

Answer 1

使用Handler代替Timer

Handler handler = new Handler();

Runnable changeImage = new Runnable(){

    @Override
    public void run(){
        if(flag>1)
           handler.removeCallbacks(changeImage);
        else{
           iv.setImageResource(v[flag++]);
           handler.postDelayed(changeImage, 1000);
        }
    }

};

从oncreate（）开始第一次

public void onCreate(Bundle b){

    handler.postDelayed(changeImage, 1000);
}

Answer 2

timer.scheduleAtFixedRate(new TimerTask() {

     public void run() {
             runOnUiThread(new Runnable() {

                 public void run() {
                     flag++;
                      if (flag > 1) {
                          timer.cancel();
                          timer = null;
                      } 
                      else
                          iv.setImageResource(v[flag]);
                     }
                 });

             }
         }, 1000, 1000); // wait 1 second before start.. then repeat every second..

Answer 3

这是因为你把System.currentTimeMillis（）作为延迟。尝试将其替换为0，因为时间应该在0 ms后开始。

在android imageview中将图像更改为1秒

3 个答案: