Android获取屏幕大小（Px）

 private DisplayMetrics dm = new DisplayMetrics();
     TextView tv;
     Button bu;
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_weather);
         tv = (TextView) findViewById(R.id.tv);
         bu = (Button) findViewById(R.id.but);
　　　　　　 //
         getWindowManager().getDefaultDisplay().getMetrics(dm);
         tv.setText(dm.widthPixels+"::"+dm.heightPixels);
     }