有三种方法，其实都是一样的，只是做了不同的封装：
private void getPhoneDisplayInfo(){
// 一
DisplayMetrics displayMetrics1 = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(displayMetrics1);
int screenWidth = displayMetrics1.widthPixels;
int screenHeight = displayMetrics1.heightPixels;
Log.d("debug", "screenWidth = "+screenWidth+"|screenHeight = "+screenHeight);
// 二
DisplayMetrics displayMetrics2 = new DisplayMetrics();
displayMetrics2 = getApplicationContext().getResources().getDisplayMetrics();
Log.d("debug", "screenWidth = "+displayMetrics2.widthPixels+"|screenHeight = "+displayMetrics2.heightPixels);
// 三
Display display = getWindowManager().getDefaultDisplay();
Log.d("debug", "screenWidth = "+display.getWidth()+"|screenHeight = "+display.getHeight());
}
