Error in the android layout when using com.facebook.widget.LoginButton

Question

I'm using Android Studio and have implemented the Facebook SDK using: File -> Import module -> "facebook" folder

Then I added this line compile project(':facebook') in the build.gradle of the app module.

Now I'm trying to add the Login Button using the com.facebook.widget.LoginButton element:

<com.facebook.widget.LoginButton
    android:id="@+id/authButton"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content" />

And I can't see the "preview" of the layout as I get this error:

java.lang.NullPointerException
at com.facebook.Settings.loadDefaultsFromMetadata(Settings.java:563)
at com.facebook.internal.Utility.getMetadataApplicationId(Utility.java:227)
at com.facebook.widget.LoginButton.checkNuxSettings(LoginButton.java:663)
at com.facebook.widget.LoginButton.onDraw(LoginButton.java:639)
at android.view.View.draw(View.java:14465)
at android.view.View.draw(View.java:14350)
at android.view.ViewGroup.drawChild(ViewGroup.java:3103)
at android.view.ViewGroup.dispatchDraw(ViewGroup.java:2940)
at android.view.View.draw(View.java:14468)
at android.view.View.draw(View.java:14350)
at android.view.ViewGroup.drawChild(ViewGroup.java:3103)
at android.view.ViewGroup.dispatchDraw(ViewGroup.java:2940)
at android.view.View.draw(View.java:14348)
at android.view.ViewGroup.drawChild(ViewGroup.java:3103)
at android.view.ViewGroup.dispatchDraw(ViewGroup.java:2940)
at android.view.View.draw(View.java:14468)
at android.view.View.draw(View.java:14350)
at android.view.ViewGroup.drawChild(ViewGroup.java:3103)
at android.view.ViewGroup.dispatchDraw(ViewGroup.java:2940)
at android.view.View.draw(View.java:14468)
at com.android.layoutlib.bridge.impl.RenderSessionImpl.render(RenderSessionImpl.java:584)
at com.android.layoutlib.bridge.Bridge.createSession(Bridge.java:338)
at com.android.ide.common.rendering.LayoutLibrary.createSession(LayoutLibrary.java:332)
at com.android.tools.idea.rendering.RenderService$3.compute(RenderService.java:560)
at com.android.tools.idea.rendering.RenderService$3.compute(RenderService.java:549)
at com.intellij.openapi.application.impl.ApplicationImpl.runReadAction(ApplicationImpl.java:932)
at com.android.tools.idea.rendering.RenderService.createRenderSession(RenderService.java:549)
at com.android.tools.idea.rendering.RenderService.render(RenderService.java:622)
at org.jetbrains.android.uipreview.AndroidLayoutPreviewToolWindowManager.doRender(AndroidLayoutPreviewToolWindowManager.java:585)
at org.jetbrains.android.uipreview.AndroidLayoutPreviewToolWindowManager.access$1900(AndroidLayoutPreviewToolWindowManager.java:80)
at org.jetbrains.android.uipreview.AndroidLayoutPreviewToolWindowManager$6$1.run(AndroidLayoutPreviewToolWindowManager.java:527)
at com.intellij.openapi.progress.impl.ProgressManagerImpl$2.run(ProgressManagerImpl.java:178)
at com.intellij.openapi.progress.ProgressManager.executeProcessUnderProgress(ProgressManager.java:209)
at com.intellij.openapi.progress.impl.ProgressManagerImpl.executeProcessUnderProgress(ProgressManagerImpl.java:212)
at com.intellij.openapi.progress.impl.ProgressManagerImpl.runProcess(ProgressManagerImpl.java:171)
at org.jetbrains.android.uipreview.AndroidLayoutPreviewToolWindowManager$6.run(AndroidLayoutPreviewToolWindowManager.java:522)
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:439)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303)
at java.util.concurrent.FutureTask.run(FutureTask.java:138)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:895)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:918)
at java.lang.Thread.run(Thread.java:695)

Does anyone know why and how I can get rid of this problem?

Answer 1

Thanks for reporting this. I work on the Android SDK at Facebook. We are going to put out a dot release of the 3.14 SDK soon to address this. But in the meantime, if you go to LoginButton.java and change the onDraw method to look like this.

@Override
protected void onDraw(Canvas canvas) {
    super.onDraw(canvas);

    if (isInEditMode()) {
        return;
    }

    if (!nuxChecked && nuxMode != ToolTipMode.NEVER_DISPLAY) {
        nuxChecked = true;
        checkNuxSettings();
    }

and then rebuild. That should fix your issue.