2010-04-15 48 views
1

考慮下面的代碼,它會保存靜態變量:mMyArray in onSaveInstanceState並將其恢復到onRestoreInstanceState中,但是我發現它根本無法保存int數組。我試過基本類型值(int),它可以保存/恢復基本類型值。靜態變量不能保存在onSaveInstanceState中?

public class StaticVarActivity extends Activity { 

    private static final String TAG = "StaticVarActivity"; 

    private static int[] mMyArray = { 1, 1 }; 

    /** Called when the activity is first created. */ 
    @Override 
    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.main); 

     Log.d(TAG, "Setting values to 2 in onCreate"); 
     mMyArray[0] = 2; 
     mMyArray[1] = 2; 

     findViewById(R.id.btn).setOnClickListener(new OnClickListener() { 

      public void onClick(View v) { 
       Log.d(TAG, "Setting values to 3 in onClick"); 
       mMyArray[0] = 3; 
       mMyArray[1] = 3; 
      } 
     }); 
    } 

    /* (non-Javadoc) 
    * @see android.app.Activity#onRestoreInstanceState(android.os.Bundle) 
    */ 
    @Override 
    protected void onRestoreInstanceState(Bundle savedInstanceState) { 
     super.onRestoreInstanceState(savedInstanceState); 

     Log.d(TAG,"onRestoreInstanceState 1:"+mMyArray[0]+","+mMyArray[1]); 
     mMyArray = savedInstanceState.getIntArray("key"); 
     Log.d(TAG,"onRestoreInstanceState 2:"+mMyArray[0]+","+mMyArray[1]); 

    } 

    /* (non-Javadoc) 
    * @see android.app.Activity#onSaveInstanceState(android.os.Bundle) 
    */ 
    @Override 
    protected void onSaveInstanceState(Bundle outState) { 
     super.onSaveInstanceState(outState); 
     Log.d(TAG,"onSaveInstanceState 1:"+mMyArray[0]+","+mMyArray[1]); 
     //int[] sss = new int[]{mMyArray[0],mMyArray[1]}; 
     //outState.putIntArray("key", sss); 
     outState.putIntArray("key", mMyArray); 
     Log.d(TAG,"onSaveInstanceState 2:"+mMyArray[0]+","+mMyArray[1]); 
    } 
} 

日誌:


04-14 15:16:00.633:DEBUG/StaticVarActivity(7251):在的onCreate 設定值至2 04-14 15:16:19.843:DEBUG/StaticVarActivity(7251):1:的onClick

//使配置改變,例如改變取向

04-14 15設定值至3 6:23.893:DEBUG/StaticVarActivity(7251):onSaveInstanceState 1:3,3 04-14 15:16:23.893:DEBUG/StaticVarActivity(7251):onSaveInstanceState 2:3,3 04-14 15:16:24.073: DEBUG/StaticVarActivity(7251):在onCreate中將值設置爲2 04-14 15:16:24.073:DEBUG/StaticVarActivity(7251):onRestoreInstanceState 1:2,2 04-14 15:16:24.073:DEBUG/StaticVarActivity 7251):onRestoreInstanceState 2:2,2


如果我更改爲:

private int[] mMyArray = { 1, 1 }; 

日誌將是:


04-14 15:18:29.183:DEBUG/StaticVarActivity(7355):在的onCreate 設定值至2 04-14 15:18:32.123:DEBUG/StaticVarActivity(7355):設置值至3在的onClick

//使配置改變,例如改變取向

04-14 15:18:33.353:DEBUG/StaticVarActivity(7355):1的onSaveInstanceState:3,3 04-14 15時十八:33.353:DEBUG/StaticVarActivity(7355):onSaveInstanceState 2:3,3 04-14 15:18:33.373:DEBUG/StaticVarActi (7355):將值設置爲onCreate 04-14 15:18:33.393:DEBUG/StaticVarActivity(7355):onRestoreInstanceState 1:2,2 04-14 15:18:33.393:DEBUG/StaticVarActivity(7355) :onRestoreInstanceState 2:3,3


我才知道它並不需要保存靜態變量,但爲什麼出現這種情況?

回答

1

AFAIK,您不能用另一個int[]替換static int[]。您可以用其他int值替換static int[]的成員。