Question

安卓开发 listView 里面有一个button控件，给该button绑定点击事件报错

Uncaught handler: thread main exiting due to uncaught exception
java.lang.NullPointerException
at com.situo.utils.MyAdapter.getView(MyAdapter.java:90)
at android.widget.AbsListView.obtainView(AbsListView.java:1273)
at android.widget.ListView.measureHeightOfChildren(ListView.java:1147)
at android.widget.ListView.onMeasure(ListView.java:1060)
at android.view.View.measure(View.java:7703)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:2989)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:888)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:350)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:278)
at android.view.View.measure(View.java:7703)
at android.widget.RelativeLayout.measureChildHorizontal(RelativeLayout.java:569)
at android.widget.RelativeLayout.onMeasure(RelativeLayout.java:361)
at android.view.View.measure(View.java:7703)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:2989)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:245)
at android.view.View.measure(View.java:7703)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:464)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:278)
at android.view.View.measure(View.java:7703)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:2989)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:245)
at android.view.View.measure(View.java:7703)
at android.view.ViewRoot.performTraversals(ViewRoot.java:747)

Answer 1

我的猜测，可能你没有实例化布局，比如说你的button id为 btn 你不能button=findViewById(R.id.btn);应该先实例化，item的布局实例化成view然后button = view.findViewById(R.id.btn);就行了!

Answer 2

你在getView()｛
是不是有这样一句话？
mAdapter = new AppListAdapter(this.mContext);
然后这么mContext没有给出构造？

｝

Answer 3

是不是自定义BaseAdapter？贴代码