我有一個簡單的ListView和ArrayAdapter。但是當android去繪製屏幕時,我每次都會得到一個空指針異常。這裏是堆棧:ListView中的Android空指針異常
Thread [<1> main] (Suspended (exception NullPointerException))
<VM does not provide monitor information>
ArrayAdapter.createViewFromResource(int, View, ViewGroup, int) line: 392
ArrayAdapter.getView(int, View, ViewGroup) line: 362
ListView(AbsListView).obtainView(int, boolean[]) line: 2210
ListView.measureHeightOfChildren(int, int, int, int, int) line: 1244
ListView.onMeasure(int, int) line: 1155
ListView(View).measure(int, int) line: 12775
LinearLayout(ViewGroup).measureChildWithMargins(View, int, int, int, int) line: 4709
LinearLayout.measureChildBeforeLayout(View, int, int, int, int, int) line: 1385
LinearLayout.measureVertical(int, int) line: 670
LinearLayout.onMeasure(int, int) line: 563
LinearLayout(View).measure(int, int) line: 12775
FrameLayout(ViewGroup).measureChildWithMargins(View, int, int, int, int) line: 4709
FrameLayout.onMeasure(int, int) line: 293
FrameLayout(View).measure(int, int) line: 12775
LinearLayout(ViewGroup).measureChildWithMargins(View, int, int, int, int) line: 4709
LinearLayout.measureChildBeforeLayout(View, int, int, int, int, int) line: 1385
LinearLayout.measureVertical(int, int) line: 670
LinearLayout.onMeasure(int, int) line: 563
LinearLayout(View).measure(int, int) line: 12775
PhoneWindow$DecorView(ViewGroup).measureChildWithMargins(View, int, int, int, int) line: 4709
PhoneWindow$DecorView(FrameLayout).onMeasure(int, int) line: 293
PhoneWindow$DecorView.onMeasure(int, int) line: 2240
PhoneWindow$DecorView(View).measure(int, int) line: 12775
ViewRootImpl.performTraversals() line: 1117
ViewRootImpl.handleMessage(Message) line: 2505
ViewRootImpl(Handler).dispatchMessage(Message) line: 99
Looper.loop() line: 137
ActivityThread.main(String[]) line: 4514
Method.invokeNative(Object, Object[], Class, Class[], Class, int, boolean) line: not available [native method]
Method.invoke(Object, Object...) line: 511
ZygoteInit$MethodAndArgsCaller.run() line: 790
ZygoteInit.main(String[]) line: 557
NativeStart.main(String[]) line: not available [native method]
代碼也很簡單。該XML:
<LinearLayout 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:background="#0099cc"
tools:context=".FullscreenActivity"
android:orientation="vertical">
<ListView
android:id="@+id/status_view"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
</ListView>
</LinearLayout>
,代碼:
String test[] = {"Line 1","Line 2"};
ListView status = (ListView) findViewById(R.id.status_view);
ArrayAdapter<String> statusList = new ArrayAdapter<String>(this,android.R.layout.simple_list_item_1,R.id.status_view,test);
status.setAdapter(statusList);
我見過噸認爲這樣做同樣的事情,當他們有一些空的字符串數組大多數人得到這個錯誤的例子在它的指針。正如你所看到的,這裏不是這種情況。任何人都與之前的戰鬥?
你確認NullPointerException異常不稱你的listView變量(狀態)?也許是(ListView)findViewById(R.id.status_view);指令返回null .. – Apperside