我在扩展“Fragment”的类中使用自定义列表视图。此自定义列表视图设置为在单击其中一个导航抽屉项目时打开。层次结构是这样的：
MainActivity.java（扩展活动）
问题是，当我不将项目点击监听器添加到onCreateView（）方法时，程序工作正常。但是，当我这样做时，日志cat会抛出指向2个位置的错误 - 一个位于声明fragment标记的部分的XML下面，另一个位于已定义项目单击监听器的MyList.java中。
我已经在MyList.java和XML文件中评论了logcat指向错误的确切位置。
为什么会这样？我希望每个列表项都可以点击，并在点击时执行一些操作。
MainActivity的XML（使用抽屉布局） -
<android.support.v4.widget.DrawerLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent">
<!-- Logcat points error on the beginning of the fragment tag -->
<fragment
class="com.example.test.MyList"
android:id="@+id/fragment1"
android:layout_width="match_parent"
android:layout_height="match_parent" />
<!-- Logcat points error here at the beginning of the fragment tag -->
<!-- Framelayout to display Fragments -->
<FrameLayout
android:id="@+id/frame_container"
android:layout_width="match_parent"
android:layout_height="match_parent" />
<!-- Listview to display slider menu -->
<ListView
android:id="@+id/list_slidermenu"
android:layout_width="240dp"
android:layout_height="match_parent"
android:layout_gravity="start"
android:choiceMode="singleChoice"
android:divider="@color/list_divider"
android:dividerHeight="1dp"
android:listSelector="@drawable/list_selector"
android:background="@color/list_background"/>
</android.support.v4.widget.DrawerLayout>
MyList.java：
import java.util.ArrayList;
import android.app.Fragment;
import android.content.Context;
import android.content.res.Resources;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.TextView;
public class MyList extends Fragment {
ListView list;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedinstanceState)
{
/* Log cat points here too, at the beginning of setOnItemClickListener */
list.setOnItemClickListener(new OnItemClickListener(){
@Override
public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
long arg3) {
System.out.println("Works!");
}
});
return inflater.inflate(R.layout.listview, container, false);
}
@Override
public void onStart() {
super.onStart();
list=(ListView)getView().findViewById(R.id.listView1);
list.setAdapter(new List1Adapter(getActivity()));
}
}
class List1Adapter extends BaseAdapter
{
ArrayList<SingleRow> list;
Context context;
List1Adapter(Context c)
{
context=c;
list=new ArrayList<SingleRow>();
Resources res=c.getResources();
String[] title=res.getStringArray(R.array.titles);
String[] description=res.getStringArray(R.array.descriptions);
int[] images={R.drawable.img1,R.drawable.img2,R.drawable.img3,R.drawable.img4};
for(int i=0;i<3;i++)
{
list.add(new SingleRow(title[i],description[i],images[i]));
}
}
@Override
public int getCount() {
// TODO Auto-generated method stub
return list.size();
}
@Override
public Object getItem(int position) {
// TODO Auto-generated method stub
return list.get(position);
}
@Override
public long getItemId(int position) {
return position;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
LayoutInflater inflater=(LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View row=inflater.inflate(R.layout.list_rows, parent, false);
TextView title=(TextView)row.findViewById(R.id.textView1);
TextView description=(TextView)row.findViewById(R.id.textView2);
ImageView image=(ImageView)row.findViewById(R.id.imageView1);
SingleRow temp=list.get(position);
title.setText(temp.title);
description.setText(temp.description);
image.setImageResource(temp.image);
return row;
}
class SingleRow
{
String title;
String description;
int image;
SingleRow(String title, String description, int image)
{
this.title=title;
this.description=description;
this.image=image;
}
}
}
logcat的：
02-14 10:25:14.248: E/ActivityThread(22106): Failed to inflate
02-14 10:25:14.248: E/ActivityThread(22106): android.view.InflateException: Binary XML file line #7: Error inflating class fragment
02-14 10:25:14.248: E/ActivityThread(22106): at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:713)
02-14 10:25:14.248: E/ActivityThread(22106): at android.view.LayoutInflater.rInflate(LayoutInflater.java:755)
02-14 10:25:14.248: E/ActivityThread(22106): at android.view.LayoutInflater.inflate(LayoutInflater.java:492)
02-14 10:25:14.248: E/ActivityThread(22106): at android.view.LayoutInflater.inflate(LayoutInflater.java:397)
02-14 10:25:14.248: E/ActivityThread(22106): at android.view.LayoutInflater.inflate(LayoutInflater.java:353)
02-14 10:25:14.248: E/ActivityThread(22106): at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:320)
02-14 10:25:14.248: E/ActivityThread(22106): at android.app.Activity.setContentView(Activity.java:1895)
02-14 10:25:14.248: E/ActivityThread(22106): at com.example.test.MainActivity.onCreate(MainActivity.java:40)
02-14 10:25:14.248: E/ActivityThread(22106): at android.app.Activity.performCreate(Activity.java:5133)
02-14 10:25:14.248: E/ActivityThread(22106): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
02-14 10:25:14.248: E/ActivityThread(22106): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2293)
02-14 10:25:14.248: E/ActivityThread(22106): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2389)
02-14 10:25:14.248: E/ActivityThread(22106): at android.app.ActivityThread.access$600(ActivityThread.java:153)
02-14 10:25:14.248: E/ActivityThread(22106): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1269)
02-14 10:25:14.248: E/ActivityThread(22106): at android.os.Handler.dispatchMessage(Handler.java:99)
02-14 10:25:14.248: E/ActivityThread(22106): at android.os.Looper.loop(Looper.java:137)
02-14 10:25:14.248: E/ActivityThread(22106): at android.app.ActivityThread.main(ActivityThread.java:5289)
02-14 10:25:14.248: E/ActivityThread(22106): at java.lang.reflect.Method.invokeNative(Native Method)
02-14 10:25:14.248: E/ActivityThread(22106): at java.lang.reflect.Method.invoke(Method.java:525)
02-14 10:25:14.248: E/ActivityThread(22106): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:739)
02-14 10:25:14.248: E/ActivityThread(22106): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:555)
02-14 10:25:14.248: E/ActivityThread(22106): at dalvik.system.NativeStart.main(Native Method)
02-14 10:25:14.248: E/ActivityThread(22106): Caused by: java.lang.NullPointerException
02-14 10:25:14.248: E/ActivityThread(22106): at com.example.test.List.onCreateView(MyList.java:27)
02-14 10:25:14.248: E/ActivityThread(22106): at android.app.Fragment.performCreateView(Fragment.java:1695)
02-14 10:25:14.248: E/ActivityThread(22106): at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:861)
02-14 10:25:14.248: E/ActivityThread(22106): at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:1035)
02-14 10:25:14.248: E/ActivityThread(22106): at android.app.FragmentManagerImpl.addFragment(FragmentManager.java:1137)
02-14 10:25:14.248: E/ActivityThread(22106): at android.app.Activity.onCreateView(Activity.java:4746)
02-14 10:25:14.248: E/ActivityThread(22106): at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:689)
02-14 10:25:14.248: E/ActivityThread(22106): ... 21 more
02-14 10:25:14.258: D/AndroidRuntime(22106): Shutting down VM
02-14 10:25:14.258: W/dalvikvm(22106): threadid=1: thread exiting with uncaught exception (group=0x415687c0)
02-14 10:25:14.268: E/AndroidRuntime(22106): FATAL EXCEPTION: main
02-14 10:25:14.268: E/AndroidRuntime(22106): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.test/com.example.test.MainActivity}: android.view.InflateException: Binary XML file line #7: Error inflating class fragment
02-14 10:25:14.268: E/AndroidRuntime(22106): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2339)
02-14 10:25:14.268: E/AndroidRuntime(22106): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2389)
02-14 10:25:14.268: E/AndroidRuntime(22106): at android.app.ActivityThread.access$600(ActivityThread.java:153)
02-14 10:25:14.268: E/AndroidRuntime(22106): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1269)
02-14 10:25:14.268: E/AndroidRuntime(22106): at android.os.Handler.dispatchMessage(Handler.java:99)
02-14 10:25:14.268: E/AndroidRuntime(22106): at android.os.Looper.loop(Looper.java:137)
02-14 10:25:14.268: E/AndroidRuntime(22106): at android.app.ActivityThread.main(ActivityThread.java:5289)
02-14 10:25:14.268: E/AndroidRuntime(22106): at java.lang.reflect.Method.invokeNative(Native Method)
02-14 10:25:14.268: E/AndroidRuntime(22106): at java.lang.reflect.Method.invoke(Method.java:525)
02-14 10:25:14.268: E/AndroidRuntime(22106): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:739)
02-14 10:25:14.268: E/AndroidRuntime(22106): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:555)
02-14 10:25:14.268: E/AndroidRuntime(22106): at dalvik.system.NativeStart.main(Native Method)
02-14 10:25:14.268: E/AndroidRuntime(22106): Caused by: android.view.InflateException: Binary XML file line #7: Error inflating class fragment
02-14 10:25:14.268: E/AndroidRuntime(22106): at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:713)
02-14 10:25:14.268: E/AndroidRuntime(22106): at android.view.LayoutInflater.rInflate(LayoutInflater.java:755)
02-14 10:25:14.268: E/AndroidRuntime(22106): at android.view.LayoutInflater.inflate(LayoutInflater.java:492)
02-14 10:25:14.268: E/AndroidRuntime(22106): at android.view.LayoutInflater.inflate(LayoutInflater.java:397)
02-14 10:25:14.268: E/AndroidRuntime(22106): at android.view.LayoutInflater.inflate(LayoutInflater.java:353)
02-14 10:25:14.268: E/AndroidRuntime(22106): at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:320)
02-14 10:25:14.268: E/AndroidRuntime(22106): at android.app.Activity.setContentView(Activity.java:1895)
02-14 10:25:14.268: E/AndroidRuntime(22106): at com.example.test.MainActivity.onCreate(MainActivity.java:40)
02-14 10:25:14.268: E/AndroidRuntime(22106): at android.app.Activity.performCreate(Activity.java:5133)
02-14 10:25:14.268: E/AndroidRuntime(22106): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
02-14 10:25:14.268: E/AndroidRuntime(22106): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2293)
02-14 10:25:14.268: E/AndroidRuntime(22106): ... 11 more
02-14 10:25:14.268: E/AndroidRuntime(22106): Caused by: java.lang.NullPointerException
02-14 10:25:14.268: E/AndroidRuntime(22106): at com.example.test.List.onCreateView(MyList.java:27)
02-14 10:25:14.268: E/AndroidRuntime(22106): at android.app.Fragment.performCreateView(Fragment.java:1695)
02-14 10:25:14.268: E/AndroidRuntime(22106): at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:861)
02-14 10:25:14.268: E/AndroidRuntime(22106): at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:1035)
02-14 10:25:14.268: E/AndroidRuntime(22106): at android.app.FragmentManagerImpl.addFragment(FragmentManager.java:1137)
02-14 10:25:14.268: E/AndroidRuntime(22106): at android.app.Activity.onCreateView(Activity.java:4746)
02-14 10:25:14.268: E/AndroidRuntime(22106): at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:689)
02-14 10:25:14.268: E/AndroidRuntime(22106): ... 21 more
答案 0 :(得分：2)
删除此导入
import android.app.Fragment;
并从支持库导入Fragment ..
import android.support.v4.app.Fragment;
你的列表对象在onCreateView方法中也是空的..所以移动这个
list.setOnItemClickListener(new OnItemClickListener(){
@Override
public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
long arg3) {
System.out.println("Works!");
}
});
到onStart方法..
答案 1 :(得分：1)
我认为它可以帮助您获得解决方案。 。
明确将OnItemClickListener添加到ListView
myList.setOnItemClickListener(this);
您还必须确保 Fragment实现OnItemClickListener 类型：
public class MainFiles extends Fragment implements OnItemClickListener
如果你有任何问题，请回复我。