我按照Facebook的教程集成了SDK,在我添加了.xml文件中的登录到Facebook按钮后,我的应用程序将编译,打开(在我的Nexus 4上运行Lollipop,针对kitkat的项目),然后崩溃.我正在全面更新
Android Studio.
logcat的：
02-07 22:48:24.340 1563-1600/com.example.prachi.mapsapplication E/AndroidRuntime﹕ FATAL EXCEPTION: AsyncTask #1
Process: com.example.prachi.mapsapplication,PID: 1563
java.lang.RuntimeException: An error occured while executing doInBackground()
at android.os.AsyncTask$3.done(AsyncTask.java:300)
at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355)
at java.util.concurrent.FutureTask.setException(FutureTask.java:222)
at java.util.concurrent.FutureTask.run(FutureTask.java:242)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
at java.lang.Thread.run(Thread.java:818)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'int java.lang.Object.hashCode()' on a null object reference
at java.util.concurrent.ConcurrentHashMap.get(ConcurrentHashMap.java:746)
at java.util.concurrent.ConcurrentHashMap.containsKey(ConcurrentHashMap.java:774)
at com.facebook.internal.Utility.queryAppSettings(Utility.java:673)
at com.facebook.widget.LoginButton$1.doInBackground(LoginButton.java:678)
at com.facebook.widget.LoginButton$1.doInBackground(LoginButton.java:675)
at android.os.AsyncTask$2.call(AsyncTask.java:288)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
at java.lang.Thread.run(Thread.java:818)
.xml：
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
android:layout_height="match_parent" android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:paddingBottom="@dimen/activity_vertical_margin" tools:context=".MainActivity"
android:id="@+id/main">
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Adventure Options"
android:id="@+id/options"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginTop="139dp"
android:onClick="optionOnClick" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Random Adventure"
android:id="@+id/random"
android:layout_marginTop="57dp"
android:onClick="randomOnClick"
android:layout_below="@+id/authButton"
android:layout_alignStart="@+id/options" />
<com.facebook.widget.LoginButton
android:id="@+id/authButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:layout_centerVertical="true"
android:layout_centerHorizontal="true" />
