應用在選擇列表首選項時崩潰

Question

我有設置活動。

public class SettingsActivity extends Activity {
private static final String TAG="SettingsActivity";
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    getFragmentManager().beginTransaction()
    .replace(android.R.id.content, new MyPreferencesFragment())
    .commit();
    Log.d(TAG,"onCreate");
}
@Override
public void onBackPressed() {
    finish();
    super.onBackPressed();
}

}

我有一個附加到此設置活動的PreferenceFragment。

public class MyPreferencesFragment extends PreferenceFragment implements
        android.content.SharedPreferences.OnSharedPreferenceChangeListener {
    private static final String TAG = "MyPreferencesFragment";
    private static final String[] values = { "send updates all the time",
            "send updates if the power is 30 percent or more(recommended)",
            "when plugged in to a power source",
            "never send location updates(not recommended)" };

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        addPreferencesFromResource(R.xml.preferences);
    }

    @Override
    public void onSharedPreferenceChanged(SharedPreferences sharedPreferences,
            String key) {
        Log.d(TAG, "onSharedPreferenceChanged");
        setSummary();

    }

    @Override
    public void onResume() {
        super.onResume();
        Log.d(TAG, "onResume");
        getPreferenceScreen().getSharedPreferences()
                .registerOnSharedPreferenceChangeListener(this);
        setSummary();
    }

    public void setSummary() {
        ListPreference pref = (ListPreference) findPreference(getString(R.string.string_key_location_settings));
        SharedPreferences sharedPref = PreferenceManager
                .getDefaultSharedPreferences(getActivity());
        if (pref != null) {
            pref.setSummary(values[Integer.valueOf(sharedPref.getString(
                    getString(R.string.string_key_location_settings), "")) - 1]);
        }
    }

}

當我第一次單擊設置並選擇一個列表項時，它可以正常工作；當我再次返回時，單擊設置，應用程序崩潰，或者至少設置活動崩潰。 錯誤日志顯示1.03-17 14:06:16.250: E/AndroidRuntime(28476): java.lang.IllegalStateException: Fragment MyPreferencesFragment{397eb568} not attached to Activity

當我打開設置活動時，但當我單擊列表設置並選擇列表項之一時，即恰好在setSummary（）時，該應用程序不會自動崩潰。 但是，第一次打開設置不會發生這種情況，但是下次打開設置活動並選擇一個列表項時，它會崩潰

我的錯誤日志

03-17 14:49:13.211: E/AndroidRuntime(25871): java.lang.IllegalStateException: Fragment MyPreferencesFragment{3add3d7c} not attached to Activity
03-17 14:49:13.211: E/AndroidRuntime(25871):    at android.app.Fragment.getResources(Fragment.java:788)
03-17 14:49:13.211: E/AndroidRuntime(25871):    at android.app.Fragment.getString(Fragment.java:810)
03-17 14:49:13.211: E/AndroidRuntime(25871):    at com.example.clickforhelp.controllers.MyPreferencesFragment.onSharedPreferenceChanged(MyPreferencesFragment.java:36)
03-17 14:49:13.211: E/AndroidRuntime(25871):    at android.app.SharedPreferencesImpl$EditorImpl.notifyListeners(SharedPreferencesImpl.java:476)
03-17 14:49:13.211: E/AndroidRuntime(25871):    at android.app.SharedPreferencesImpl$EditorImpl.apply(SharedPreferencesImpl.java:384)
03-17 14:49:13.211: E/AndroidRuntime(25871):    at android.preference.Preference.tryCommit(Preference.java:1403)
03-17 14:49:13.211: E/AndroidRuntime(25871):    at android.preference.Preference.persistString(Preference.java:1436)
03-17 14:49:13.211: E/AndroidRuntime(25871):    at android.preference.ListPreference.setValue(ListPreference.java:147)
03-17 14:49:13.211: E/AndroidRuntime(25871):    at android.preference.ListPreference.onDialogClosed(ListPreference.java:282)
03-17 14:49:13.211: E/AndroidRuntime(25871):    at android.preference.DialogPreference.onDismiss(DialogPreference.java:391)
03-17 14:49:13.211: E/AndroidRuntime(25871):    at android.app.Dialog$ListenersHandler.handleMessage(Dialog.java:1257)
03-17 14:49:13.211: E/AndroidRuntime(25871):    at android.os.Handler.dispatchMessage(Handler.java:102)
03-17 14:49:13.211: E/AndroidRuntime(25871):    at android.os.Looper.loop(Looper.java:135)
03-17 14:49:13.211: E/AndroidRuntime(25871):    at android.app.ActivityThread.main(ActivityThread.java:5312)
03-17 14:49:13.211: E/AndroidRuntime(25871):    at java.lang.reflect.Method.invoke(Native Method)
03-17 14:49:13.211: E/AndroidRuntime(25871):    at java.lang.reflect.Method.invoke(Method.java:372)
03-17 14:49:13.211: E/AndroidRuntime(25871):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:901)
03-17 14:49:13.211: E/AndroidRuntime(25871):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:696)

Answer 1

將代碼從onCreate移到onActivityCreated而不是嘗試在onCreate上進行getActivity

將片段添加為您的活動為

FragmentTransaction fragTrans = getFragmentManager().beginTransaction();
fragTrans.replace(android.R.id.content, new PreferenceFragment()).commit();