Question

简单的问题。我做了一个settingsActivity并且做了一个sharedPrefernecesLIstener。它运行良好，所以我独自留下来制作其余的应用程序。我回到它来完成一些事情，发现它停止工作了。我浏览了Stack Overflow上的一些问题并阅读了一些内容，但没有答案。日志说： W/InputEventReceiver: Attempted to finish an input event but the input event receiver has already been disposed. 搜索此内容不会给我答案，因为答案通常是针对我无法解决问题的特定实例。例如：An Input is Disposed。我不在我的深度之内，所以我转向询问这个问题。

public class SettingsActivity extends AppCompatActivity {
static final String TAG = "SettingsActivity";
public static final String SHARED_PREFS = "sharedPrefs";
public static final String PREF_NETWORK_TYPE = "network_choice";
public static final String WIFI = "WiFi";
public static final String FIRST = "First";
public static final String WIFI_PREFERENCE = "WiFi Enabled";
public static final String NO_PREFERENCE = "First Enabled";
public String sPref = null;
private NetworkCheck networkCheck;
SharedPreferences sharedPrefs;
SharedPreferences.OnSharedPreferenceChangeListener listener;
private boolean prefWifi = false;
private boolean noPreferredNetwork = true;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.settings_activity);
    networkCheck = new NetworkCheck();
    getSupportFragmentManager()
            .beginTransaction()
            .replace(R.id.settings, new SettingsFragment())
            .commit();
    ActionBar actionBar = getSupportActionBar();
    if (actionBar != null) {
        actionBar.setDisplayHomeAsUpEnabled(true);
    }
    PreferenceManager.setDefaultValues(this, R.xml.root_preferences, false);

    IntentFilter filter = new IntentFilter(CONNECTIVITY_SERVICE);
    this.registerReceiver(networkCheck, filter);

    if (savedInstanceState == null) {
        sharedPrefs = PreferenceManager.getDefaultSharedPreferences(this);
        sPref = sharedPrefs.getString(PREF_NETWORK_TYPE, "First");
        if (sPref == null) {
            sPref = FIRST;
        }
        switch (sPref) {
            case WIFI:
                prefWifi = true;
                noPreferredNetwork = false;
                break;
            case FIRST:
                prefWifi = false;
                noPreferredNetwork = true;
                break;
            default:
                prefWifi = false;
                noPreferredNetwork = true;
        }
    }
    Log.i(TAG, "onSharedPreferenceChanged: onCreate - " + sPref + " " + prefWifi + " " + noPreferredNetwork);

    listener = (sharedPreferences, key) -> {
        if (key.equals(PREF_NETWORK_TYPE)) {
            Toast.makeText(SettingsActivity.this, "Tell me this works", Toast.LENGTH_LONG).show();
        }
    };
    listener = (sharedPreferences, key) -> {


        if (key.equals(PREF_NETWORK_TYPE)) {
            sPref = sharedPrefs.getString(PREF_NETWORK_TYPE, "First");
            if (sPref == null) {
                sPref = FIRST;
            }
            prefWifi = sPref.equals(WIFI);
            noPreferredNetwork = sPref.equals(FIRST);
            if (prefWifi) {
                sPref = WIFI;
            } else if (noPreferredNetwork) {
                sPref = FIRST;
            }
            networkType();

            Log.i(TAG, "onSharedPreferenceChanged: in listener- " + sPref + " " + prefWifi + " " + noPreferredNetwork);
        }
    };
    networkType();

}


@Override
public void onDestroy() {
    super.onDestroy();
    if (networkCheck != null) {
        this.unregisterReceiver(networkCheck);
    }
}

@Override
public void onResume() {
    super.onResume();
    sharedPrefs.registerOnSharedPreferenceChangeListener(listener);
}

@Override
public void onPause() {
    super.onPause();
    networkType();
    Log.i(TAG, "onSharedPreferenceChanged: onPause- " + sPref + " " + prefWifi + " " + noPreferredNetwork);
    sharedPrefs.unregisterOnSharedPreferenceChangeListener(listener);
}

public void networkType() {
    sharedPrefs = getSharedPreferences(SHARED_PREFS, MODE_PRIVATE);
    SharedPreferences.Editor editor = sharedPrefs.edit();
    editor.putBoolean(WIFI_PREFERENCE, prefWifi);
    editor.putBoolean(NO_PREFERENCE, noPreferredNetwork);
    editor.apply();

    Log.i(TAG, "onSharedPreferenceChanged: networkType- " + " " + "prefWifi: " + prefWifi + " " + "noPreferredNetwork: " + noPreferredNetwork);

}

public static class SettingsFragment extends PreferenceFragmentCompat {

    @Override
    public void onCreatePreferences(Bundle savedInstanceState, String rootKey) {
        setPreferencesFromResource(R.xml.root_preferences, rootKey);
    }
}
}

有趣的是，List Preference在我下次打开应用程序时有效，但是Listener不起作用。

更新： 下面的root_preferences是调用PREF_NETWORK_TYPE变量的地方。或者应该被调用。

<PreferenceCategory
    android:key="network"
    android:title="Network">

  <ListPreference
      android:key="network_choice"
      android:title="Network Connection Type"
      android:summary="Choose the Network connection you to use to access the Internet"
      android:entries="@array/pref_connectionType"
      android:entryValues="@array/pref_connectionType_values"
      android:defaultValue="First"/>
</PreferenceCategory>

SharedPreferencesListener没有明显原因停止工作

0 个答案: