方法是activityview的onWindowFocusChanged事件時可以取得特定view長寬
@Override
public void onWindowFocusChanged(boolean hasFocus) {
super.onWindowFocusChanged(hasFocus);
ImageView imgView= (ImageView)findViewById(R.id.imageview_activities_a);
Log.w("myApp", Integer.toString(imgView.getHeight()));