Android onRestoreInstanceState覆盖值

Question

所以我对onSaveInstanceState和onRestoreInstanceState有个奇怪的问题。下面是我到现在为止所拥有的，而且工作得很好。方法的调用，值保存和恢复都很好。

@Override
public void onRestoreInstanceState(Bundle savedInstanceState) {
  // Always call the superclass so it can restore the view hierarchy
  super.onRestoreInstanceState(savedInstanceState);

  // Restore value of members from saved state
  mRawImgPath = savedInstanceState.getString(SAVE_STATE_RAW_IMG_PATH);
  mProImgPath = savedInstanceState.getString(SAVE_STATE_PRO_IMG_PATH);
}

@Override
public void onSaveInstanceState(Bundle savedInstanceState) {
  // Always call the superclass so it can save the view hierarchy state
  super.onSaveInstanceState(savedInstanceState);

  // Save the user's current game state
  savedInstanceState.putString(SAVE_STATE_RAW_IMG_PATH, mRawImgPath);
  savedInstanceState.putString(SAVE_STATE_PRO_IMG_PATH, mProImgPath);
}

现在，我想用我希望保存的第三个值来增强代码。

@Override
public void onRestoreInstanceState(Bundle savedInstanceState) {
  // Always call the superclass so it can restore the view hierarchy
  super.onRestoreInstanceState(savedInstanceState);

  // Restore value of members from saved state
  mRawImgPath = savedInstanceState.getString(SAVE_STATE_RAW_IMG_PATH);
  mProImgPath = savedInstanceState.getString(SAVE_STATE_PRO_IMG_PATH);
  mLastState = savedInstanceState.getString(SAVE_STATE_LAST_STATE);
}

@Override
public void onSaveInstanceState(Bundle savedInstanceState) {
  // Always call the superclass so it can save the view hierarchy state
  super.onSaveInstanceState(savedInstanceState);

  // Save the user's current game state
  savedInstanceState.putString(SAVE_STATE_RAW_IMG_PATH, mRawImgPath);
  savedInstanceState.putString(SAVE_STATE_PRO_IMG_PATH, mProImgPath);
  savedInstanceState.putString(SAVE_STATE_LAST_STATE, mLastState);
}

方法仍然被完美地调用，但是它不再恢复正确的值了。我没有将正确的值还原到正确的变量中，而是将SAVE_STATE_LAST_STATE还原到所有三个vars中(mRawImgPath、mProImgPath和mLastState)。

我可以说的是，他们在onSaveInstanceState()保存时有正确的值，所以他们在保存时不会有错误的值。另外，我不会在onCreate()中更改值，否则第一个解决方案(只有两个变量)也不能工作。我真的不知道那里发生了什么。

如果感兴趣的话，下面是声明：

// Vars
GPSTracker gps;
String mRawImgPath = ""; // Path of the raw image
String mProImgPath = ""; // Path of the processed image
String mLastState = "";

// Save state variables
static final String SAVE_STATE_RAW_IMG_PATH = "";
static final String SAVE_STATE_PRO_IMG_PATH = "";
static final String SAVE_STATE_LAST_STATE = "";

任何帮助都是非常感谢的。

Answer 1

static final String SAVE_STATE_RAW_IMG_PATH = "";
static final String SAVE_STATE_PRO_IMG_PATH = "";
static final String SAVE_STATE_LAST_STATE = "";

您有空名，请更改为：

static final String SAVE_STATE_RAW_IMG_PATH = "SAVE_STATE_RAW_IMG_PATH";
static final String SAVE_STATE_PRO_IMG_PATH = "SAVE_STATE_PRO_IMG_PATH";
static final String SAVE_STATE_LAST_STATE = "SAVE_STATE_LAST_STATE";