最近对我的代码库进行了一些重大的重构（主要是将类移到新的包中），现在我在用户登录后尝试启动NavigationDrawer活动时遇到错误。
DistributorLogin运行一个asynctask来验证用户的凭据，并返回一个Distributor对象，该对象作为额外的函数传递给启动NavigationDrawer的Intent。在startActivity（Intent）运行后的某个时刻，在设置活动时会发生对Context.getResources（）的调用。看来资源对象返回null。一些设备在ContextThemeWrapper.initializeTheme（int）中出现此错误，并且我在尝试检索布尔值时也看到它发生在Window.getDefaultFeatures（Context）中。只有在尝试启动NavDrawer活动时才会出现此问题。其他活动似乎开始很好。永远不会调用NavDrawer的onCreate（）。
DistributorLogin.activity
@Override
public void distributorAuthenticationFinished(Distributor output) {
try {
//Only continue if a valid Distributor object was received
if (output != null) {
String currentLanguage = "ENG";
DistributorSettings distributorSettings = output.getDistributorSettings();
if (distributorSettings != null) {
String homeCountry = distributorSettings.getHomeCountry();
currentLanguage = distributorSettings.getCurrentLanguage();
Content.getInstance().setCurrentLocale(homeCountry, currentLanguage);
writeContentDocs(homeCountry, currentLanguage, false);
writeAllSupportedLanguageDocs();
}
//Clear UI element values
etxt_name.setText("");
etxt_password.setText("");
//Attempt to register a new device token if one is not already saved.
Intent tokenIntent = IntentCreator.getTokenRegistrationIntent(this, RegistrationTokenIntentService.CREATE_NEW_IF_NONE_EXISTS,
Distributor.distributorId, Distributor.homeCountry, currentLanguage);
startService(tokenIntent);
// Start the main activity
Intent intent = new Intent(this, NavDrawer.class);
intent.putExtra(getString(R.string.cb_parameter_distributor), output);
startActivity(intent);
}
} catch (Exception e) {
Log.e(TAG, "Error starting nav drawer activity.", e);
}
}
Android清单
<manifest
package="com.marketamerica.android.unfranchiseprospecting"
xmlns:android="http://schemas.android.com/apk/res/android">
<application
android:name=".models.Ufp"
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme"
android:uiOptions="splitActionBarWhenNarrow">
<activity
android:name=".activities.DistributorLogin"
android:label="@string/app_name_acronym"
android:windowSoftInputMode="adjustPan">
<intent-filter>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
</activity>
<activity
android:name=".activities.NavDrawer"
android:label="@string/title_activity_nav_drawer"
android:windowSoftInputMode="adjustPan"
android:launchMode="singleTop"/>
</application>
</manifest>
NavDrawer
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
ufpTypeFace = Typeface.createFromAsset(getAssets(), "fonts/ufp_2-0.ttf");
isTablet = Ufp.getIsTablet();
// Get application resources
resources = this.getResources();
// Define our sharedPreferences and editor objects
sharedPreferences = getSharedPreferences(resources.getString(R.string.ma_content_shared_prefs_name), Context.MODE_PRIVATE);
sharedPreferencesEditor = sharedPreferences.edit();
checkAndResetSharedPrefsIfNecessary();
// Set the initial fragmentState
if (savedInstanceState == null) {
fragmentState = FragmentState.viewable;
sharedPreferencesEditor.putString("fragmentState", "viewable");
sharedPreferencesEditor.apply();
} else {
shouldRestoreMediaDetail = savedInstanceState.getBoolean(getString(R.string.media_detail_arg_key));
}
restoreSelectedProspectId(sharedPreferences);
if (!selectedProspectId.equals("")) {
prospectDetails = repository.get(getString(R.string.cb_parameter_prospect_doc_prefix) + selectedProspectId, ProspectDetails.class);
}
// Assign our Distributor object from CB
distributor = (Distributor) getIntent().getSerializableExtra(getString(R.string.cb_parameter_distributor));
// ThreadPoolExecutors responsible for updating prospectDetailsArrayList and timelineItemArrayList
detailsThreadPoolExecutor = new ThreadPoolExecutor(1, 1, 1, TimeUnit.SECONDS, new LinkedBlockingQueue<Runnable>());
timelineThreadPoolExecutor = new ThreadPoolExecutor(1, 1, 1, TimeUnit.SECONDS, new LinkedBlockingQueue<Runnable>());;
startProspectDetailsLiveQuery();
startTimelineLiveQuery();
// Instantiate fragmentManager
fragmentManager = getFragmentManager();
// Set up our content views and layouts
if (!isTablet) { // Handset layout
setContentView(R.layout.activity_nav_drawer);
container = (FrameLayout) findViewById(R.id.container);
drawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
setupFloatingActionButton();
setUpToolbar();
} else { // Tablet layout
setContentView(R.layout.activity_nav_drawer_tablet);
container = (FrameLayout) findViewById(R.id.container);
drawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
setupFloatingActionButton();
setUpToolbar();
}
if (mNavigationDrawerFragment == null) {
// Instantiate the NavigationDrawer
mNavigationDrawerFragment = (NavigationDrawerFragment)
getFragmentManager().findFragmentById(R.id.navigation_drawer);
if (drawerLayout != null) {
// Set up the drawer.
mNavigationDrawerFragment.setUp(
R.id.navigation_drawer,
drawerLayout);
}
}
// Instantiate prospectListFragment and corresponding layout for UI control if device is a tablet
if (Ufp.getIsTablet()) {
prospectListFragment = (ProspectListFragment) fragmentManager.findFragmentById(R.id.prospects_list);
prospectListFragmentLayout = prospectListFragment.getView();
}
logcat的
09-07 15:48:51.644 24077-24077/com.marketamerica.android.unfranchiseprospecting E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.marketamerica.android.unfranchiseprospecting, PID: 24077
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.marketamerica.android.unfranchiseprospecting/com.marketamerica.android.unfranchiseprospecting.activities.NavDrawer}:
java.lang.NullPointerException: Attempt to invoke virtual method 'android.content.res.Resources$Theme android.content.res.Resources.newTheme()' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2814)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2879)
at android.app.ActivityThread.access$900(ActivityThread.java:182)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1475)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:145)
at android.app.ActivityThread.main(ActivityThread.java:6141)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1399)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1194)
Caused by: java.lang.NullPointerException:
Attempt to invoke virtual method 'android.content.res.Resources$Theme android.content.res.Resources.newTheme()' on a null object reference
at android.view.ContextThemeWrapper.initializeTheme(ContextThemeWrapper.java:134)
at android.view.ContextThemeWrapper.setTheme(ContextThemeWrapper.java:85)
at android.support.v7.app.AppCompatActivity.setTheme(AppCompatActivity.java:86)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2760)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2879)
at android.app.ActivityThread.access$900(ActivityThread.java:182)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1475)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:145)
at android.app.ActivityThread.main(ActivityThread.java:6141)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1399)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1194)