im working on an android project an i want to put a Facebook Login feature, i added the Facebook sdk Correctly but i could not initialize LoginButton
**java.lang.NoClassDefFoundError: Could not initialize class com.facebook.login.widget.LoginButton**
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
at org.jetbrains.android.uipreview.ViewLoader.createNewInstance(ViewLoader.java:413)
at org.jetbrains.android.uipreview.ViewLoader.loadView(ViewLoader.java:105)
at com.android.tools.idea.rendering.LayoutlibCallback.loadView(LayoutlibCallback.java:176)
at android.view.BridgeInflater.loadCustomView(BridgeInflater.java:207)
at android.view.BridgeInflater.createViewFromTag(BridgeInflater.java:132)
at android.view.LayoutInflater.rInflate_Original(LayoutInflater.java:806)
at android.view.LayoutInflater_Delegate.rInflate(LayoutInflater_Delegate.java:64)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:782)
at android.view.LayoutInflater.inflate(LayoutInflater.java:504)
at android.view.LayoutInflater.inflate(LayoutInflater.java:385)
at com.android.layoutlib.bridge.impl.RenderSessionImpl.inflate(RenderSessionImpl.java:400)
at com.android.layoutlib.bridge.Bridge.createSession(Bridge.java:332)
at com.android.ide.common.rendering.LayoutLibrary.createSession(LayoutLibrary.java:350)
at com.android.tools.idea.rendering.RenderService$5.compute(RenderService.java:708)
at com.android.tools.idea.rendering.RenderService$5.compute(RenderService.java:697)
at com.intellij.openapi.application.impl.ApplicationImpl.runReadAction(ApplicationImpl.java:932)
at com.android.tools.idea.rendering.RenderService.createRenderSession(RenderService.java:697)
at com.android.tools.idea.rendering.RenderService.render(RenderService.java:816)
at com.intellij.android.designer.designSurface.AndroidDesignerEditorPanel$6.run(AndroidDesignerEditorPanel.java:480)
at com.intellij.util.ui.update.MergingUpdateQueue.execute(MergingUpdateQueue.java:320)
at com.intellij.util.ui.update.MergingUpdateQueue.execute(MergingUpdateQueue.java:310)
at com.intellij.util.ui.update.MergingUpdateQueue$2.run(MergingUpdateQueue.java:254)
at com.intellij.util.ui.update.MergingUpdateQueue.flush(MergingUpdateQueue.java:269)
at com.intellij.util.ui.update.MergingUpdateQueue.flush(MergingUpdateQueue.java:227)
at com.intellij.util.ui.update.MergingUpdateQueue.run(MergingUpdateQueue.java:217)
at com.intellij.util.concurrency.QueueProcessor.runSafely(QueueProcessor.java:238)
at com.intellij.util.Alarm$Request$1.run(Alarm.java:327)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
at java.util.concurrent.FutureTask.run(FutureTask.java:262)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:745)
here is my AppManifest.xml :
<?xml version="1.0" encoding="utf-8"?>
<uses-permission android:name="android.permission.INTERNET"/>
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name=".helloActivity"
android:label="@string/title_activity_hello" >
</activity>
<activity android:name="com.facebook.FacebookActivity"
android:configChanges=
"keyboard|keyboardHidden|screenLayout|screenSize|orientation"
android:theme="@android:style/Theme.Translucent.NoTitleBar"
android:label="@string/app_name" />
<meta-data android:name="com.facebook.sdk.ApplicationId" android:value="@string/app_id"/>
</application>
I specified the App_id in Strings.xml. Thanks for help
This is due to non-initialization of FacebookSdk before its usage. Just add below line:
FacebookSdk.sdkInitialize(mContext);
in case host of LoginButton is:
1.Activity- before setContentView(R.layout.activity_main)
2.Fragment- before inflater.inflate(R.layout.fragment_main, container, false)
Also don't forget to listen the callback in onActivityResult() in above cases to update the UI of LoginButton.
I checked on latest SDK4.0.1, in that com.facebook.login.widget.LoginButton is available. But this was not found in facebook-android-sdk-3.17.1, there we have only com.facebook.widget.LoginButton available. Facebook didn't notified the developers or in their changelogs that LoginButton class moved to sub folder.
Very strange why facebook not updating correctly.. Even the doc for Android login is wrong!!
Add this to you Manifest.xml
<meta-data android:name="com.facebook.sdk.ApplicationId" android:value="@string/facebook_app_id" />
<meta-data android:name="com.facebook.sdk.ApplicationName" android:value="@string/app_name" />
来源：https://stackoverflow.com/questions/29316447/could-not-initialize-loginbutton-facebook-sdk-for-android