Question

我开发了一个带有firebase的Android应用程序，它运行良好。我决定用websocket而不是Firebase重用我的代码。在一些帮助下，我正在开发它，并且它进展顺利。但我有一个组件的问题。

当我在一个活动中尝试打开一个包含带有android.r.layout.simple_list_item_multiple_choice的列表视图的对话框时出现了麻烦。在那一刻，应用程序崩溃了......错误显示出来了。

我调试在对话框中加载信息的代码并显示没有错误...我找不到空对象或'由'引起的，通常它有助于找到可能是错误的位置......

06-12 00:59:56.718 2289-2289/wazodevs.com.coletask E/AndroidRuntime: FATAL EXCEPTION: main
        Process: wazodevs.com.coletask, PID: 2289
        java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String java.lang.Object.toString()' on a null object reference
            at android.widget.ArrayAdapter.createViewFromResource(ArrayAdapter.java)
            at android.widget.ArrayAdapter.getView(ArrayAdapter.java)
            at android.widget.AbsListView.obtainView(AbsListView.java)
            at android.widget.ListView.makeAndAddView(ListView.java)
            at android.widget.ListView.fillDown(ListView.java)
            at android.widget.ListView.fillFromTop(ListView.java)
            at android.widget.ListView.layoutChildren(ListView.java)
            at android.widget.AbsListView.onLayout(AbsListView.java)
            at android.view.View.layout(View.java)
            at android.view.ViewGroup.layout(ViewGroup.java)
            at android.widget.LinearLayout.setChildFrame(LinearLayout.java)
            at android.widget.LinearLayout.layoutHorizontal(LinearLayout.java)
            at android.widget.LinearLayout.onLayout(LinearLayout.java)
            at android.view.View.layout(View.java)
            at android.view.ViewGroup.layout(ViewGroup.java)
            at android.widget.LinearLayout.setChildFrame(LinearLayout.java)
            at android.widget.LinearLayout.layoutVertical(LinearLayout.java)
            at android.widget.LinearLayout.onLayout(LinearLayout.java)
            at android.view.View.layout(View.java)
            at android.view.ViewGroup.layout(ViewGroup.java)
            at android.widget.RelativeLayout.onLayout(RelativeLayout.java)
            at android.view.View.layout(View.java)
            at android.view.ViewGroup.layout(ViewGroup.java)
            at android.widget.FrameLayout.layoutChildren(FrameLayout.java)
            at android.widget.FrameLayout.onLayout(FrameLayout.java)
            at android.view.View.layout(View.java)
            at android.view.ViewGroup.layout(ViewGroup.java)
            at android.widget.FrameLayout.layoutChildren(FrameLayout.java)
            at android.widget.FrameLayout.onLayout(FrameLayout.java)
            at android.view.View.layout(View.java)
            at android.view.ViewGroup.layout(ViewGroup.java)
            at android.widget.LinearLayout.setChildFrame(LinearLayout.java)
            at android.widget.LinearLayout.layoutVertical(LinearLayout.java)
            at android.widget.LinearLayout.onLayout(LinearLayout.java)
            at android.view.View.layout(View.java)
            at android.view.ViewGroup.layout(ViewGroup.java)
            at android.widget.FrameLayout.layoutChildren(FrameLayout.java)
            at android.widget.FrameLayout.onLayout(FrameLayout.java)
            at android.view.View.layout(View.java)
            at android.view.ViewGroup.layout(ViewGroup.java)
            at android.view.ViewRootImpl.performLayout(ViewRootImpl.java)
            at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java)
            at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java)
            at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java)
            at android.view.Choreographer$CallbackRecord.run(Choreographer.java)
            at android.view.Choreographer.doCallbacks(Choreographer.java)
            at android.view.Choreographer.doFrame(Choreographer.java)
            at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java)
            at android.os.Handler.handleCallback(Handler.java)
            at android.os.Handler.dispatchMessage(Handler.java)
            at android.os.Looper.loop(Looper.java)
            at android.app.ActivityThread.main(ActivityThread.java)
            at java.lang.reflect.Method.invoke(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:372)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java)
06-12 00:59:57.008 356-1014/? E/BandwidthController: No such appUid 10117 to remove

Thx 4 all！

Answer 1

我在对话框中调试加载信息的代码并在没有显示的情况下显示错误...我无法找到空对象或由＆＃39;引起的＆＃39;通常它有助于找到错误的位置......

您的数据集包含空值。在内部，ArrayAdapter执行以下检查：

final T item = getItem(position);
if (item instanceof CharSequence) {
    text.setText((CharSequence) item);
 } else {
    text.setText(item.toString());
 }

这是createViewFromResource上toString被称为

的唯一地方

Answer 2

答案非常愚蠢....问题是我必须创建一个字符串列表来加载arrayadapter，而aImages有8个元素，但是ObtainImgs过滤并填充8个中的3个...但是没有＆＃39; t检查员上的null ...但是当你试图继续......坠毁...... Thx伙计们！

String [] listArray = new String [aImages.length]; listArray = obtainImgs（listArray）;

Android应用程序崩溃而没有引起

2 个答案: