android设置横竖屏切换时生命周期不会改变

android:configChanges="keyboardHidden|orientation|screenSize"

<activity android:name=".MainActivity"
    android:configChanges="keyboardHidden|orientation|screenSize"/>

 添加了这句代码后，在发生横竖屏切换时activity 的生命周期不会改变
 下面的这个方法才会有效

@Override
public void onConfigurationChanged(Configuration newConfig) {
    super.onConfigurationChanged(newConfig);

    Configuration cfg = getResources().getConfiguration();

    if (cfg.orientation == Configuration.ORIENTATION_LANDSCAPE) {
        Toast.makeText(this, "横屏", Toast.LENGTH_SHORT).show();
    } else if (cfg.orientation == Configuration.ORIENTATION_PORTRAIT) {
        Toast.makeText(this, "竖屏", Toast.LENGTH_SHORT).show();
    }
}