实例_活动被系统意外回收时_保留临时数据onSaveInstanceState(Bundle outState)

public class MainActivity extends Activity
{
    private EditText et;
    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        //
        //小技巧:
        //MainActivity.this.getClass().getName().toString()----------<package name>.<instance name>
        //MainActivity.this.getClass().getSimpleName().toString()----<instance name>
        //
        Log.e(MainActivity.this.getClass().getSimpleName().toString(), "开始了");
        et = (EditText) findViewById(R.id.et);
        if(savedInstanceState != null)
        {    
            String tempData = savedInstanceState.getString("key");//temp 临时的
            et.setText(tempData);
            et.setSelection(tempData.length());
        }
    }
    
    @Override
    protected void onSaveInstanceState(Bundle outState)//state 国家 规定 情形 n/v
    {
        super.onSaveInstanceState(outState);
        String tempData = et.getText().toString();
        outState.putString("key", tempData);
    }
}