如何在中心點上旋轉一個android圖標？

Question

我已經寫了下面的代碼來讓我的圖標旋轉到屏幕的中心，而是圍繞左上角（即ImageView的原點x = 0，y = 0）旋轉。設置ImageView或RotateAnimation的某些屬性應該很簡單，但我無法弄清楚。

public class IconPromoActivity extends Activity { 
    private static final float ROTATE_FROM = 0.0f; 
    private static final float ROTATE_TO = -10.0f * 360.0f;// 3.141592654f * 32.0f; 

    /** Called when the activity is first created. */ 
    @Override 
    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.main); 

     ImageView favicon = (ImageView) findViewById(R.id.favicon); 

     RotateAnimation r; // = new RotateAnimation(ROTATE_FROM, ROTATE_TO); 
     r = new RotateAnimation(ROTATE_FROM, ROTATE_TO, 0, 0, 40, 0); 
     r.setDuration((long) 2*1500); 
     r.setRepeatCount(0); 
     favicon.startAnimation(r); 
    } 
} 

Answer 1

嘗試： r = new RotateAnimation(ROTATE_FROM, ROTATE_TO, Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF, 0.5f);

Answer 2

這個工作對我來說：

img = (ImageView)findViewById(R.id.ImageView01); 
RotateAnimation rotateAnimation = new RotateAnimation(30, 90, 
    Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF, 0.5f);