java - Android for循环在主线程中不起作用

Question

我尝试旋转图像。我用 runnable 来旋转图像，我写了循环，我想在循环内旋转图像 这是我的来源

public void rotateimages(final View myView) {
    myHandler = new Handler();
    runnable = new Runnable() {

        @Override
        public void run() {

            double k = 30;

            double speed = Math.PI / k;
            for (alpa = 0; alpa < (Math.PI * 6 + res * 2 * Math.PI / 5); alpa += speed) {

                myView.setRotation((float) (myView.getRotation() - alpa));

                Log.e("alpa values", String.valueOf(alpa));

                k = Math.min(k + 0.2, 240);
                speed = Math.PI / k;
                myHandler.postDelayed(this, 100); 
            }
            // rotateimages();
        }

    };

    myHandler.postDelayed(runnable, 180);
}

当我运行我的应用程序时，我只能旋转一次。我的代码有什么问题吗？如果有人知道解决方案请帮助我

Answer 1

如果你想循环，你需要自己重新定义这个'runnable'循环 将您的代码编辑为:

myHandler = new Handler();
count = 0;
public void rotateImage(final View myView, final int size) {


    runnable = new Runnable() {

        @Override
        public void run() {

            count++;
            myView.setRotation(myView.getRotation() + size);
            if(count == 10){
               myHandler.removeCallBack(runnable );
            }
           myHandler.postDelayed(this, 1000); // 1000 means 1 second duration
         }
        };
        myHandler.postDelayed(runnable, 180); // 180 is the delay after new runnable is going to called

}

如何循环自身，这意味着一行代码，或者一条语句再次调用事件。一些例子:

 void nothing(int a){
   if(a> 0)
     nothing(a-1);
   }

然后什么都不调用(10)。仅此而已，并避免以下行为:

void nothing(int a){
       for(int i =0; i< a;i++) 
         nothing(a-1);                //BIG WRONG
       }
 Do you know your solution?