转载

Android -- 获取View宽高

在activity中可以调用View.getWidth、View.getHeight()、View.getMeasuredWidth() 、View.getgetMeasuredHeight()来获得某个view的宽度或高度，但是在onCreate()、onStrart()、onResume()方法中会返回0，这是应为当前activity所代表的界面还没显示出来没有添加到WindowPhone的DecorView上或要获取的view没有被添加到DecorView上或者该View的visibility属性为gone 或者该view的width或height真的为0 ，所以只有上述条件都不成立时才能得到非0的width和height。

View的事件回调里使用

这时候该view已经被显示即被添加到DecorView上如点击事件触摸事件焦点事件等

View view=findViewById(R.id.tv);       view.setOnClickListener(new OnClickListener() {                      @Override           public void onClick(View v) {               int width = v.getWidth();           }       });

onWindowFocusChanged() 回调

在activity被显示出来时即添加到了DecorView上时获取宽和高如onWindowFocusChanged() 回调方法

@Override   public void onWindowFocusChanged(boolean hasFocus) {    View iv1 = findViewById(R.id.iv1);    View iv2=findViewById(R.id.iv2);    String msg1="iv1' width:"+iv1.getWidth()+" height:"+iv1.getHeight()+"   measuredWidth:"+iv1.getMeasuredWidth()+"measuredHeight:"+iv1.getMeasuredHeight();    String msg2="iv2' width:"+iv2.getWidth()+" height:"+iv2.getHeight()+"   measuredWidth:"+iv2.getMeasuredWidth()+"measuredHeight:"+iv2.getMeasuredHeight();    Log.i("onWindowFocusChanged() "+msg1);    Log.i("onWindowFocusChanged() "+msg2);    super.onWindowFocusChanged(hasFocus);   }

延时

在onResume方法最后开线程300毫秒左右后获取宽和高因为onResume执行完后300毫秒后，界面就显示出来了。

view.postDelayed(new Runnable() {    @Override    public void run() {     View iv1 = findViewById(R.id.iv1);     View iv2=findViewById(R.id.iv2);     String msg1="iv1' width:"+iv1.getWidth()+" height:"+iv1.getHeight()+"  measuredWidth:"+iv1.getMeasuredWidth()+"measuredHeight:"+iv1.getMeasuredHeight();     String msg2="iv2' width:"+iv2.getWidth()+" height:"+iv2.getHeight()+"  measuredWidth:"+iv2.getMeasuredWidth()+"measuredHeight:"+iv2.getMeasuredHeight();     Log.i("onWindowFocusChanged() "+msg1);     Log.i("onWindowFocusChanged() "+msg2);    }   }, 300);

在onCreate()或onResume()等方法中需要

getViewTreeObserver().addOnGlobalLayoutListener()来添为view加回调在回调里获得宽度或者高度获取完后让view删除该回调

view.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {    @Override    public void onGlobalLayout() {     view.postDelayed(new Runnable() {      @Override      public void run() {       View iv1 = findViewById(R.id.iv1);       View iv2=findViewById(R.id.iv2);       String msg1="iv1' width:"+iv1.getWidth()+" height:"+iv1.getHeight()+"  measuredWidth:"+iv1.getMeasuredWidth()+"measuredHeight:"+iv1.getMeasuredHeight();       String msg2="iv2' width:"+iv2.getWidth()+" height:"+iv2.getHeight()+"  measuredWidth:"+iv2.getMeasuredWidth()+"measuredHeight:"+iv2.getMeasuredHeight();       Log.i("onWindowFocusChanged() "+msg1);       Log.i("onWindowFocusChanged() "+msg2);      }     }, 300);    }   });