Android -- 获取View宽高

浏览数：23 / 时间：2015年06月11日

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);  
        }  
    });