问题描述
我想乱用新RecyclerView,每当我尝试运行它,我的应用程序立即崩溃。它给我的NullPointerException从 android.support.v7.widget.RecyclerView
试图访问方法。我看着其他职位,看到大多数人没有编译com.android.support:recyclerview-v7:+
,但我想,它不是招'T帮助都没有。真的不知道该怎么做,在这一点上,任何帮助,将AP preciated。在这里,错误日志:(我会发布图片,但我没有10代表还)
显示java.lang.NullPointerException:尝试调用虚拟方法无效android.support.v7.widget.RecyclerView$LayoutManager.onMeasure(android.support.v7.widget.RecyclerView$Recycler, android.support.v7.widget.RecyclerView $州,在一个空对象引用INT,INT)
在android.support.v7.widget.RecyclerView.onMeasure(RecyclerView.java:1764)
在android.view.View.measure(View.java:17430)
在android.widget.RelativeLayout.measureChildHorizontal(RelativeLayout.java:727)
在android.widget.RelativeLayout.onMeasure(RelativeLayout.java:463)
在android.view.View.measure(View.java:17430)
在android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5463)
在android.widget.FrameLayout.onMeasure(FrameLayout.java:430)
在android.view.View.measure(View.java:17430)
在android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5463)
在android.widget.FrameLayout.onMeasure(FrameLayout.java:430)
在android.view.View.measure(View.java:17430)
在android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5463)
在android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1436)
在android.widget.LinearLayout.measureVertical(LinearLayout.java:722)
在android.widget.LinearLayout.onMeasure(LinearLayout.java:613)
在android.view.View.measure(View.java:17430)
在android.support.v4.widget.DrawerLayout.onMeasure(DrawerLayout.java:851)
在android.view.View.measure(View.java:17430)
在android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5463)
在android.widget.FrameLayout.onMeasure(FrameLayout.java:430)
在android.view.View.measure(View.java:17430)
在android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5463)
在android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1436)
在android.widget.LinearLayout.measureVertical(LinearLayout.java:722)
在android.widget.LinearLayout.onMeasure(LinearLayout.java:613)
在android.view.View.measure(View.java:17430)
在android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5463)
在android.widget.FrameLayout.onMeasure(FrameLayout.java:430)
在android.view.View.measure(View.java:17430)
在android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5463)
在android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1436)
在android.widget.LinearLayout.measureVertical(LinearLayout.java:722)
在android.widget.LinearLayout.onMeasure(LinearLayout.java:613)
在android.view.View.measure(View.java:17430)
在android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5463)
在android.widget.FrameLayout.onMeasure(FrameLayout.java:430)
在com.android.internal.policy.impl.PhoneWindow $ DecorView.onMeasure(PhoneWindow.java:2560)
在android.view.View.measure(View.java:17430)
在android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:2001)
在android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1166)
在android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1372)
在android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1054)
在android.view.ViewRootImpl $ TraversalRunnable.run(ViewRootImpl.java:5786)
在android.view.Choreographer $ CallbackRecord.run(Choreographer.java:767)
在android.view.Choreographer.doCallbacks(Choreographer.java:580)
在android.view.Choreographer.doFrame(Choreographer.java:550)
在android.view.Choreographer $ FrameDisplayEventReceiver.run(Choreographer.java:753)
在android.os.Handler.handleCallback(Handler.java:739)
在android.os.Handler.dispatchMessage(Handler.java:95)
在android.os.Looper.loop(Looper.java:135)
在android.app.ActivityThread.main(ActivityThread.java:5221)
在java.lang.reflect.Method.invoke(本机方法)
在java.lang.reflect.Method.invoke(Method.java:372)
在com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run(ZygoteInit.java:898)
在com.android.internal.os.ZygoteInit.main(ZygoteInit.java:693)
这个问题通常发生在没有<$c$c>LayoutManager$c$c>商为<$c$c>RecyclerView$c$c>.你可以做到这一点,像这样:
最后LinearLayoutManager的layoutManager =新LinearLayoutManager(上下文);
layoutManager.setOrientation(LinearLayoutManager.VERTICAL);
recyclerView.setLayoutManager(的layoutManager);
I'm trying to mess with the new RecyclerView and whenever I try to run it, my app immediately crashes. It gives me NullPointerException for trying to access methods from android.support.v7.widget.RecyclerView
. I've looked at other posts and saw that most people didn't have compile 'com.android.support:recyclerview-v7:+'
but I tried that and it hasn't helped at all. Not really sure what to do at this point, any help would be appreciated. Here the error log: (I would post a picture but I don't have 10 rep yet)
java.lang.NullPointerException: Attempt to invoke virtual method 'void android.support.v7.widget.RecyclerView$LayoutManager.onMeasure(android.support.v7.widget.RecyclerView$Recycler, android.support.v7.widget.RecyclerView$State, int, int)' on a null object reference
at android.support.v7.widget.RecyclerView.onMeasure(RecyclerView.java:1764)
at android.view.View.measure(View.java:17430)
at android.widget.RelativeLayout.measureChildHorizontal(RelativeLayout.java:727)
at android.widget.RelativeLayout.onMeasure(RelativeLayout.java:463)
at android.view.View.measure(View.java:17430)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5463)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:430)
at android.view.View.measure(View.java:17430)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5463)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:430)
at android.view.View.measure(View.java:17430)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5463)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1436)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:722)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:613)
at android.view.View.measure(View.java:17430)
at android.support.v4.widget.DrawerLayout.onMeasure(DrawerLayout.java:851)
at android.view.View.measure(View.java:17430)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5463)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:430)
at android.view.View.measure(View.java:17430)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5463)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1436)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:722)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:613)
at android.view.View.measure(View.java:17430)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5463)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:430)
at android.view.View.measure(View.java:17430)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5463)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1436)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:722)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:613)
at android.view.View.measure(View.java:17430)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5463)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:430)
at com.android.internal.policy.impl.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2560)
at android.view.View.measure(View.java:17430)
at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:2001)
at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1166)
at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1372)
at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1054)
at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:5786)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:767)
at android.view.Choreographer.doCallbacks(Choreographer.java:580)
at android.view.Choreographer.doFrame(Choreographer.java:550)
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:753)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5221)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:898)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:693)
This issue usually occurs when no LayoutManager
was provided for the RecyclerView
. You can do it like so:
final LinearLayoutManager layoutManager = new LinearLayoutManager(context);
layoutManager.setOrientation(LinearLayoutManager.VERTICAL);
recyclerView.setLayoutManager(layoutManager);
这篇关于应用轰然试图用RecyclerView在Android 5.0时,的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持!