错误日志

11-25 16:09:10.965 22791-22823/myapplication.com.myblue E/HAL: hw_get_module_by_class: lib loaded: /system/lib/hw/gralloc.msm8909.so
11-25 16:09:24.875 22791-22791/myapplication.com.myblue E/ywq: android.bluetooth.device.action.FOUND
11-25 16:09:24.895 22791-22791/myapplication.com.myblue E/AndroidRuntime: FATAL EXCEPTION: main
                                                                          Process: myapplication.com.myblue, PID: 22791
                                                                          java.lang.NullPointerException: Attempt to invoke virtual method 'int android.view.View.getImportantForAccessibility()' on a null object reference
                                                                              at android.widget.AbsListView.obtainView(AbsListView.java:2385)
                                                                              at android.widget.ListView.makeAndAddView(ListView.java:1868)
                                                                              at android.widget.ListView.fillDown(ListView.java:702)
                                                                              at android.widget.ListView.fillFromTop(ListView.java:763)
                                                                              at android.widget.ListView.layoutChildren(ListView.java:1663)
                                                                              at android.widget.AbsListView.onLayout(AbsListView.java:2169)
                                                                              at android.view.View.layout(View.java:15743)
                                                                              at android.view.ViewGroup.layout(ViewGroup.java:5051)
                                                                              at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1734)
                                                                              at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1588)
                                                                              at android.widget.LinearLayout.onLayout(LinearLayout.java:1497)
                                                                              at android.view.View.layout(View.java:15743)
                                                                              at android.view.ViewGroup.layout(ViewGroup.java:5051)
                                                                              at android.widget.FrameLayout.layoutChildren(FrameLayout.java:579)
                                                                              at android.widget.FrameLayout.onLayout(FrameLayout.java:514)
                                                                              at android.view.View.layout(View.java:15743)
                                                                              at android.view.ViewGroup.layout(ViewGroup.java:5051)
                                                                              at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1734)
                                                                              at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1588)
                                                                              at android.widget.LinearLayout.onLayout(LinearLayout.java:1497)
                                                                              at android.view.View.layout(View.java:15743)
                                                                              at android.view.ViewGroup.layout(ViewGroup.java:5051)
                                                                              at android.widget.FrameLayout.layoutChildren(FrameLayout.java:579)
                                                                              at android.widget.FrameLayout.onLayout(FrameLayout.java:514)
                                                                              at android.view.View.layout(View.java:15743)
                                                                              at android.view.ViewGroup.layout(ViewGroup.java:5051)
                                                                              at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1734)
                                                                              at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1588)
                                                                              at android.widget.LinearLayout.onLayout(LinearLayout.java:1497)
                                                                              at android.view.View.layout(View.java:15743)
                                                                              at android.view.ViewGroup.layout(ViewGroup.java:5051)
                                                                              at android.widget.FrameLayout.layoutChildren(FrameLayout.java:579)
                                                                              at android.widget.FrameLayout.onLayout(FrameLayout.java:514)
                                                                              at android.view.View.layout(View.java:15743)
                                                                              at android.view.ViewGroup.layout(ViewGroup.java:5051)
                                                                              at android.view.ViewRootImpl.performLayout(ViewRootImpl.java:2153)
                                                                              at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1907)
                                                                              at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1105)
                                                                              at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:6204)
                                                                              at android.view.Choreographer$CallbackRecord.run(Choreographer.java:799)
                                                                              at android.view.Choreographer.doCallbacks(Choreographer.java:612)
                                                                              at android.view.Choreographer.doFrame(Choreographer.java:581)
                                                                              at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:785)
                                                                              at android.os.Handler.handleCallback(Handler.java:739)
                                                                              at android.os.Handler.dispatchMessage(Handler.java:95)
                                                                              at android.os.Looper.loop(Looper.java:135)
                                                                              at android.app.ActivityThread.main(ActivityThread.java:5593)
                                                                              at java.lang.reflect.Method.invoke(Native Method)
                                                                              at java.lang.reflect.Method.invoke(Method.java:372)
                                                                              at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:967)
                                                                              at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:762)
11-25 16:09:25.375 24146-24146/myapplication.com.myblue E/HAL: hw_get_module_by_class: lib loaded: /system/lib/hw/gralloc.msm8909.so
11-25 16:09:25.505 24146-24174/myapplication.com.myblue E/HAL: hw_get_module_by_class: lib loaded: /system/lib/hw/gralloc.msm8909.so
11-25 16:09:25.505 24146-24174/myapplication.com.myblue E/HAL: hw_get_module_by_class: lib loaded: /system/lib/hw/gralloc.msm8909.so
11-25 16:09:27.235 24146-24174/myapplication.com.myblue E/HAL: hw_get_module_by_class: lib loaded: /system/lib/hw/gralloc.msm8909.so
11-25 16:09:28.225 24146-24146/myapplication.com.myblue E/ywq: android.bluetooth.adapter.action.DISCOVERY_FINISHED
11-25 16:10:54.245 24146-24146/myapplication.com.myblue E/ywq: android.bluetooth.device.action.FOUND
11-25 16:10:54.255 24146-24146/myapplication.com.myblue E/AndroidRuntime: FATAL EXCEPTION: main
                                                                          Process: myapplication.com.myblue, PID: 24146
                                                                          java.lang.NullPointerException: Attempt to invoke virtual method 'int android.view.View.getImportantForAccessibility()' on a null object reference
                                                                              at android.widget.AbsListView.obtainView(AbsListView.java:2385)
                                                                              at android.widget.ListView.makeAndAddView(ListView.java:1868)
                                                                              at android.widget.ListView.fillDown(ListView.java:702)
                                                                              at android.widget.ListView.fillFromTop(ListView.java:763)
                                                                              at android.widget.ListView.layoutChildren(ListView.java:1663)
                                                                              at android.widget.AbsListView.onLayout(AbsListView.java:2169)
                                                                              at android.view.View.layout(View.java:15743)
                                                                              at android.view.ViewGroup.layout(ViewGroup.java:5051)
                                                                              at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1734)
                                                                              at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1588)
                                                                              at android.widget.LinearLayout.onLayout(LinearLayout.java:1497)
                                                                              at android.view.View.layout(View.java:15743)
                                                                              at android.view.ViewGroup.layout(ViewGroup.java:5051)
                                                                              at android.widget.FrameLayout.layoutChildren(FrameLayout.java:579)
                                                                              at android.widget.FrameLayout.onLayout(FrameLayout.java:514)
                                                                              at android.view.View.layout(View.java:15743)
                                                                              at android.view.ViewGroup.layout(ViewGroup.java:5051)
                                                                              at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1734)
                                                                              at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1588)
                                                                              at android.widget.LinearLayout.onLayout(LinearLayout.java:1497)
                                                                              at android.view.View.layout(View.java:15743)
                                                                              at android.view.ViewGroup.layout(ViewGroup.java:5051)
                                                                              at android.widget.FrameLayout.layoutChildren(FrameLayout.java:579)
                                                                              at android.widget.FrameLayout.onLayout(FrameLayout.java:514)
                                                                              at android.view.View.layout(View.java:15743)
                                                                              at android.view.ViewGroup.layout(ViewGroup.java:5051)
                                                                              at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1734)
                                                                              at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1588)
                                                                              at android.widget.LinearLayout.onLayout(LinearLayout.java:1497)
                                                                              at android.view.View.layout(View.java:15743)
                                                                              at android.view.ViewGroup.layout(ViewGroup.java:5051)
                                                                              at android.widget.FrameLayout.layoutChildren(FrameLayout.java:579)
                                                                              at android.widget.FrameLayout.onLayout(FrameLayout.java:514)
                                                                              at android.view.View.layout(View.java:15743)
                                                                              at android.view.ViewGroup.layout(ViewGroup.java:5051)
                                                                              at android.view.ViewRootImpl.performLayout(ViewRootImpl.java:2153)
                                                                              at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1907)
                                                                              at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1105)
                                                                              at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:6204)
                                                                              at android.view.Choreographer$CallbackRecord.run(Choreographer.java:799)
                                                                              at android.view.Choreographer.doCallbacks(Choreographer.java:612)
                                                                              at android.view.Choreographer.doFrame(Choreographer.java:581)
                                                                              at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:785)
                                                                              at android.os.Handler.handleCallback(Handler.java:739)
                                                                              at android.os.Handler.dispatchMessage(Handler.java:95)
                                                                              at android.os.Looper.loop(Looper.java:135)
                                                                              at android.app.ActivityThread.main(ActivityThread.java:5593)
                                                                              at java.lang.reflect.Method.invoke(Native Method)
                                                                              at java.lang.reflect.Method.invoke(Method.java:372)
                                                                              at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:967)
                                                                              at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:762)

1.

对应的Adapter的getView方法返回为空，出现的这个空指针现象。

  @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder holder;
        if(convertView==null){
            convertView= LayoutInflater.from(context).inflate(R.layout.searchitem_layout, null);
            holder=new ViewHolder();
            holder.textViewl=(TextView) convertView.findViewById(R.id.textView_item);
            convertView.setTag(holder);
        }else{
            holder=(ViewHolder) convertView.getTag();
        }
        String s=datas.get(position);
        holder.textViewl.setText("MAC:"+s);

        return convertView;
    }