savedInstanceState保存状态的一个问题
从网上看到一段代码是关于savedInstanceState保存状态的。进入程序后会执行onCreate,打出log,按home键会执行
onSaveInstanceState,打出log。
问题一:onRestoreInstanceState这个函数并没有执行,log没有打出来,这个函数在什么情况下才会执行呢
问题二:按home键推出后,再返回是不会执行onCreate的,那onCreate中写了
if(null != savedInstanceState)
{
int IntTest = savedInstanceState.getInt("IntTest");
String StrTest = savedInstanceState.getString("StrTest");
Log.e(TAG, "onCreate get the savedInstanceState+IntTest="+IntTest+"+StrTest="+StrTest);
}
是做什么用的呢?
package com.myandroid.test;
import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
public class AndroidTest extends Activity {
private static final String TAG = "MyNewLog";
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// If an instance of this activity had previously stopped, we can
// get the original text it started with.
if(null != savedInstanceState)
{
int IntTest = savedInstanceState.getInt("IntTest");
String StrTest = savedInstanceState.getString("StrTest");
Log.e(TAG, "onCreate get the savedInstanceState+IntTest="+IntTest+"+StrTest="+StrTest);
}
setContentView(R.layout.main);
Log.e(TAG, "onCreate");
}
@Override
public void onSaveInstanceState(Bundle savedInstanceState) {
// Save away the original text, so we still have it if the activity
// needs to be killed while paused.
savedInstanceState.putInt("IntTest", 0);
savedInstanceState.putString("StrTest", "savedInstanceState test");
super.onSaveInstanceState(savedInstanceState);
Log.e(TAG, "onSaveInstanceState");
}
@Override
public void onRestoreInstanceState(Bundle savedInstanceState) {
super.onRestoreInstanceState(savedInstanceState);
int IntTest = savedInstanceState.getInt("IntTest");
String StrTest = savedInstanceState.getString("StrTest");
Log.e(TAG, "onRestoreInstanceState+IntTest="+IntTest+"+StrTest="+StrTest);
}
}