应用程序在某些随机设备上崩溃

Question

今天我在我的应用程序中遇到了一个奇怪的问题。所以在第一个 activity 中，有一个导航抽屉，其中一些项目列在列表视图中（在抽屉中）。导航抽屉中有滚动条。现在，在一些随机设备上出现问题。应用程序正常启动，但只要我滚动（内部导航抽屉），应用程序就会崩溃。 Eclipse 抛出 NullPointer 异常。我不明白，因为问题发生在某些设备上，但在其他设备上却完美无缺。我正在 posting logcat 以及其他相关文件。

Logcat:

02-16 18:54:46.879: E/AndroidRuntime(1654): FATAL EXCEPTION: main
02-16 18:54:46.879: E/AndroidRuntime(1654): Process: com.example.passpass, PID: 1654
02-16 18:54:46.879: E/AndroidRuntime(1654): java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.TextView.setText(java.lang.CharSequence)' on a null object reference
02-16 18:54:46.879: E/AndroidRuntime(1654):     at com.example.passpass.adapter.NavDrawerListAdapter.getView(NavDrawerListAdapter.java:89)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.widget.AbsListView.obtainView(AbsListView.java:2344)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.widget.ListView.makeAndAddView(ListView.java:1864)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.widget.ListView.fillDown(ListView.java:698)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.widget.ListView.fillGap(ListView.java:662)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.widget.AbsListView.trackMotionScroll(AbsListView.java:4968)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.widget.AbsListView.scrollIfNeeded(AbsListView.java:3398)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.widget.AbsListView.onTouchMove(AbsListView.java:3774)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.widget.AbsListView.onTouchEvent(AbsListView.java:3612)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.View.dispatchTouchEvent(View.java:8388)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2424)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2158)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2430)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2172)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2430)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2172)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2430)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2172)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2430)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2172)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at com.android.internal.policy.impl.PhoneWindow$DecorView.superDispatchTouchEvent(PhoneWindow.java:2314)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at com.android.internal.policy.impl.PhoneWindow.superDispatchTouchEvent(PhoneWindow.java:1692)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.app.Activity.dispatchTouchEvent(Activity.java:2739)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchTouchEvent(PhoneWindow.java:2275)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.View.dispatchPointerEvent(View.java:8578)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.ViewRootImpl$ViewPostImeInputStage.processPointerEvent(ViewRootImpl.java:4021)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.ViewRootImpl$ViewPostImeInputStage.onProcess(ViewRootImpl.java:3887)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:3449)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.ViewRootImpl$InputStage.onDeliverToNext(ViewRootImpl.java:3502)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.ViewRootImpl$InputStage.forward(ViewRootImpl.java:3468)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.ViewRootImpl$AsyncInputStage.forward(ViewRootImpl.java:3578)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.ViewRootImpl$InputStage.apply(ViewRootImpl.java:3476)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.ViewRootImpl$AsyncInputStage.apply(ViewRootImpl.java:3635)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:3449)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.ViewRootImpl$InputStage.onDeliverToNext(ViewRootImpl.java:3502)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.ViewRootImpl$InputStage.forward(ViewRootImpl.java:3468)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.ViewRootImpl$InputStage.apply(ViewRootImpl.java:3476)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:3449)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.ViewRootImpl.deliverInputEvent(ViewRootImpl.java:5701)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.ViewRootImpl.doProcessInputEvents(ViewRootImpl.java:5675)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.ViewRootImpl.enqueueInputEvent(ViewRootImpl.java:5646)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.ViewRootImpl$WindowInputEventReceiver.onInputEvent(ViewRootImpl.java:5791)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.InputEventReceiver.dispatchInputEvent(InputEventReceiver.java:185)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.InputEventReceiver.nativeConsumeBatchedInputEvents(Native Method)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.InputEventReceiver.consumeBatchedInputEvents(InputEventReceiver.java:176)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.ViewRootImpl.doConsumeBatchedInput(ViewRootImpl.java:5762)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.ViewRootImpl$ConsumeBatchedInputRunnable.run(ViewRootImpl.java:5814)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.Choreographer$CallbackRecord.run(Choreographer.java:767)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.Choreographer.doCallbacks(Choreographer.java:580)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.Choreographer.doFrame(Choreographer.java:548)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:753)
02-16 18:54:46.879: E/AndroidRuntime(1654):     at

Adapter 的 Getview 方法 Logcat 正在讨论

public class NavDrawerListAdapter 扩展了 BaseAdapter {

private Context context;
private ArrayList<Category> navDrawerItems;

public NavDrawerListAdapter(Context context, ArrayList<Category> navDrawerItems){
    this.context = context;
    this.navDrawerItems = navDrawerItems;
}

@Override
public int getCount() {
    return navDrawerItems.size();
}

@Override
public Object getItem(int position) {       
    return navDrawerItems.get(position);
}

@Override
public int getItemViewType(int position) {
    // TODO Auto-generated method stub
    int type=3;
    if(navDrawerItems.get(position).getId()==0)
        type=0;
    else if(navDrawerItems.get(position).getId()==10)
        type=10;
    else 
        type=1;
    return type;

}

@Override
public long getItemId(int position) {
    return position;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {


    int type = getItemViewType(position);
    if(type==0)
    {
    if (convertView == null) {
        LayoutInflater mInflater = (LayoutInflater)
                context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        convertView = mInflater.inflate(R.layout.drawer_list_item, null);
    }


    TextView txtTitle = (TextView) convertView.findViewById(R.id.title);
    txtTitle.setText(navDrawerItems.get(position).getName());



}

else if(type==1)
{

    if (convertView == null) {
        LayoutInflater mInflater = (LayoutInflater)
                context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        convertView = mInflater.inflate(R.layout.drawer_list_item_sub, null);
    }


    TextView txtTitle = (TextView) convertView.findViewById(R.id.title);
    txtTitle.setText(navDrawerItems.get(position).getName()); //Eclipse is throwing NPE here
}
else
{

    if (convertView == null) {
        LayoutInflater mInflater = (LayoutInflater)
                context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        convertView = mInflater.inflate(R.layout.home, null);
    }


    TextView txtTitle = (TextView) convertView.findViewById(R.id.home);
    txtTitle.setText(navDrawerItems.get(position).getName());

}
     return convertView;

}
}

XML 文件：这是我用于导航抽屉的不同行的三种布局之一。

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="48dp" 
    android:background="@drawable/list_selector">



    <TextView
        android:id="@+id/title"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_marginLeft="55dp"
        android:minHeight="?android:attr/listPreferredItemHeightSmall"
        android:textAppearance="?android:attr/textAppearanceListItemSmall"
        android:textColor="@color/list_item_title"
        android:gravity="center_vertical"
        android:paddingRight="40dp"
        android:textSize="10dp"/>



</RelativeLayout>

导致问题的原因是什么？请告诉我是否需要我 post 导航抽屉代码或布局文件。

提前致谢

Answer 1

您似乎使用了三种不同的物品类型，而且您很尊重 convertView。这意味着 OS 给你的布局可能与你期望的不同，因为它正在被回收。例如，您可能会返回 home 布局，但它似乎没有 title 视图。

要纠正这个问题，您要么需要跟踪您扩充了哪种类型的布局，例如，通过添加 tag and/or viewholder 模式；或者您需要忽略回收视图并始终膨胀视图。

应用程序在某些随机设备上崩溃

App crashing on some random devices

android

android-listview

android-adapter

android-fragments

android-navigation