こんにちは、私もこの問題に遭遇しました。私にとってそれを修正したのは:
@Override
public void onSaveInstanceState(Bundle savedInstanceState) {
// Save the user's current game state
savedInstanceState.putString("Username", mUsername);
savedInstanceState.putString("Password", mPassword);
savedInstanceState.putString("UserID", mUserID);
// Always call the superclass so it can save the view hierarchy state
super.onSaveInstanceState(savedInstanceState);
}
そして onCreate() で:
if (savedInstanceState == null) {
Bundle extras = getIntent().getExtras();
if(extras == null) {
mUsername = "?";
mPassword = "?";
mUserID = "?";
} else {
mUsername = extras.getString("Username");
mPassword = extras.getString("Password");
mUserID = extras.getString("UserID");
}
} else {
mUsername = (String) savedInstanceState.getSerializable("Username");
mPassword = (String) savedInstanceState.getSerializable("Password");
mUserID = (String) savedInstanceState.getSerializable("UserID");
}
オブジェクトが null でないことを確認できます。