Android 为什么我设置ListView时应用程序崩溃?
我正在尝试运行一个例子,我在一本关于Android 为什么我设置ListView时应用程序崩溃?,android,android-listview,android-arrayadapter,Android,Android Listview,Android Arrayadapter,我正在尝试运行一个例子,我在一本关于列表视图的书中找到了这个例子。正如书中所述,我在string.xml文件中创建了string数组,而ListView的布局在list\u item.xml的res->layout文件夹中 问题是,当我运行活动时,应用程序崩溃。谁能告诉我错误在哪里吗 代码1: public class ListViewTestActivity extends ListActivity { /** Called when the activity is first created
列表视图的书中找到了这个例子。正如书中所述,我在string.xml
文件中创建了string数组
,而ListView
的布局在list\u item.xml
的res->layout
文件夹中
问题是,当我运行活动时,应用程序崩溃。谁能告诉我错误在哪里吗
代码1:
public class ListViewTestActivity extends ListActivity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
String[] c = getResources().getStringArray(R.array.cities);
setListAdapter(new ArrayAdapter<String>(this, R.layout.list_item, c));
}}
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<TextView
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:textSize="28dip">
</TextView>
</LinearLayout>
05-05 22:45:16.018: E/ArrayAdapter(648): You must supply a resource ID for a TextView
05-05 22:45:16.048: E/AndroidRuntime(648): FATAL EXCEPTION: main
05-05 22:45:16.048: E/AndroidRuntime(648): java.lang.IllegalStateException: ArrayAdapter requires the resource ID to be a TextView
05-05 22:45:16.048: E/AndroidRuntime(648): at android.widget.ArrayAdapter.createViewFromResource(ArrayAdapter.java:347)
05-05 22:45:16.048: E/AndroidRuntime(648): at android.widget.ArrayAdapter.getView(ArrayAdapter.java:323)
05-05 22:45:16.048: E/AndroidRuntime(648): at android.widget.AbsListView.obtainView(AbsListView.java:1430)
05-05 22:45:16.048: E/AndroidRuntime(648): at android.widget.ListView.makeAndAddView(ListView.java:1745)
05-05 22:45:16.048: E/AndroidRuntime(648): at android.widget.ListView.fillDown(ListView.java:670)
05-05 22:45:16.048: E/AndroidRuntime(648): at android.widget.ListView.fillFromTop(ListView.java:727)
05-05 22:45:16.048: E/AndroidRuntime(648): at android.widget.ListView.layoutChildren(ListView.java:1598)
05-05 22:45:16.048: E/AndroidRuntime(648): at android.widget.AbsListView.onLayout(AbsListView.java:1260)
05-05 22:45:16.048: E/AndroidRuntime(648): at android.view.View.layout(View.java:7175)
05-05 22:45:16.048: E/AndroidRuntime(648): at android.widget.FrameLayout.onLayout(FrameLayout.java:338)
05-05 22:45:16.048: E/AndroidRuntime(648): at android.view.View.layout(View.java:7175)
05-05 22:45:16.048: E/AndroidRuntime(648): at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1254)
05-05 22:45:16.048: E/AndroidRuntime(648): at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1130)
05-05 22:45:16.048: E/AndroidRuntime(648): at android.widget.LinearLayout.onLayout(LinearLayout.java:1047)
05-05 22:45:16.048: E/AndroidRuntime(648): at android.view.View.layout(View.java:7175)
05-05 22:45:16.048: E/AndroidRuntime(648): at android.widget.FrameLayout.onLayout(FrameLayout.java:338)
05-05 22:45:16.048: E/AndroidRuntime(648): at android.view.View.layout(View.java:7175)
05-05 22:45:16.048: E/AndroidRuntime(648): at android.view.ViewRoot.performTraversals(ViewRoot.java:1140)
05-05 22:45:16.048: E/AndroidRuntime(648): at android.view.ViewRoot.handleMessage(ViewRoot.java:1859)
05-05 22:45:16.048: E/AndroidRuntime(648): at android.os.Handler.dispatchMessage(Handler.java:99)
05-05 22:45:16.048: E/AndroidRuntime(648): at android.os.Looper.loop(Looper.java:130)
05-05 22:45:16.048: E/AndroidRuntime(648): at android.app.ActivityThread.main(ActivityThread.java:3683)
05-05 22:45:16.048: E/AndroidRuntime(648): at java.lang.reflect.Method.invokeNative(Native Method)
05-05 22:45:16.048: E/AndroidRuntime(648): at java.lang.reflect.Method.invoke(Method.java:507)
05-05 22:45:16.048: E/AndroidRuntime(648): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
05-05 22:45:16.048: E/AndroidRuntime(648): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
05-05 22:45:16.048: E/AndroidRuntime(648): at dalvik.system.NativeStart.main(Native Method)
05-05 22:45:16.048: E/AndroidRuntime(648): Caused by: java.lang.ClassCastException: android.widget.LinearLayout
05-05 22:45:16.048: E/AndroidRuntime(648): at android.widget.ArrayAdapter.createViewFromResource(ArrayAdapter.java:340)
您的xml文件必须如下所示:
<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/monid"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:textSize="28dip" />
您可能正在关闭list\u item.xml中的线性布局。
如果这不起作用,发布日志您可能需要调用onCreate中的某个地方的setContentView(…)。如果您对行项目使用该特定布局,则将id
分配给文本视图
,并将其传递到适配器的构造函数中,以让适配器知道将数据放置在何处:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<TextView
android:id="@+id/text"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:textSize="28dip">
</TextView>
在你的活动中:
setListAdapter(new ArrayAdapter<String>(this, R.layout.list_item, R.id.text, c));
setListAdapter(新的ArrayAdapter(this,R.layout.list_项,R.id.text,c));
你真的写了这句话:android:id=“@+id/idyouwant”
你也可以发布日志吗?发布日志后,我们可以更好地帮助您。
setListAdapter(new ArrayAdapter<String>(this, R.layout.list_item, R.id.text, c));