Android:GCM上更新ListView收到崩溃我的应用程序

非常感谢您的帮助，当我收到GCM推送通知时，我的应用程序不断崩溃，当我尝试更新我的listView时，它崩溃，以下是完整代码：

GCM课程（全部）：

public class MyGcmListenerService extends GcmListenerService {

private static final String TAG = "MyGcmListenerService";

/**
 * Called when message is received.
 *
 * @param from SenderID of the sender.
 * @param data Data bundle containing message data as key/value pairs.
 *             For Set of keys use data.keySet().
 */
// [START receive_message]
@Override
public void onMessageReceived(String from, Bundle data) {
    String message = data.getString("m");
    Log.d(TAG, "From: " + from);
    Log.d(TAG, "Message: " + message);

    if(myDbHelper.checkDataBase()) {
        DataBaseHelper gsh = new DataBaseHelper(getApplicationContext());
        gsh.getSQLiteHistory();
    }

    sendNotification(message);

}
// [END receive_message]

/**
 * Create and show a simple notification containing the received GCM message.
 *
 * @param message GCM message received.
 */

private void sendNotification(String message) {
    Intent intent = new Intent(this, MainActivity.class);
    intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
    PendingIntent pendingIntent = PendingIntent.getActivity(this, 0 /* Request code */, intent,
            PendingIntent.FLAG_ONE_SHOT);

    Uri defaultSoundUri= RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
    NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(this)
            .setSmallIcon(R.drawable.ic_stat_ic_notification)
            .setContentTitle("my alert")
            .setContentText(message)
            .setAutoCancel(true)
            .setSound(defaultSoundUri)
            .setContentIntent(pendingIntent);

    NotificationManager notificationManager =
            (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);

    notificationManager.notify(0 /* ID of notification */, notificationBuilder.build());
}
}

public void GCMRefresh(List<RowItem> rowItems)
{
    adapter = new CustomListViewAdapter(this.getActivity(),
                R.layout.list_item, rowItems); //CRASH HERE
    mList.setAdapter(adapter);
}

public class CustomListViewAdapter extends ArrayAdapter<RowItem> {

    Context context;

    public CustomListViewAdapter(Context context, int resourceId,
                                 List<RowItem> items) {
        super(context, resourceId, items);
        this.context = context;
    }

    /*private view holder class*/
    private class ViewHolder {
        ImageView imageView;
        TextView txtTitle;
        TextView txtDesc;
    }

    public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder holder = null;
        RowItem rowItem = getItem(position);

        LayoutInflater mInflater = (LayoutInflater) context
                .getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
        if (convertView == null) {
            convertView = mInflater.inflate(R.layout.list_item, null);
            holder = new ViewHolder();
            holder.txtDesc = (TextView) convertView.findViewById(R.id.desc);
            holder.txtTitle = (TextView) convertView.findViewById(R.id.title);
            holder.imageView = (ImageView) convertView.findViewById(R.id.icon);
            convertView.setTag(holder);
        } else
            holder = (ViewHolder) convertView.getTag();

        holder.txtDesc.setText(rowItem.getDesc());
        holder.txtTitle.setText(rowItem.getTitle());
        holder.imageView.setImageResource(rowItem.getImageId());

        return convertView;
    }
}

从SQL类中，我调用“newalertslist（）.GCMRefresh（rowItems）；”

现在，当我有我的项目列表时，我在AlertList类中调用GCMRefresh:

public class MyGcmListenerService extends GcmListenerService {

private static final String TAG = "MyGcmListenerService";

/**
 * Called when message is received.
 *
 * @param from SenderID of the sender.
 * @param data Data bundle containing message data as key/value pairs.
 *             For Set of keys use data.keySet().
 */
// [START receive_message]
@Override
public void onMessageReceived(String from, Bundle data) {
    String message = data.getString("m");
    Log.d(TAG, "From: " + from);
    Log.d(TAG, "Message: " + message);

    if(myDbHelper.checkDataBase()) {
        DataBaseHelper gsh = new DataBaseHelper(getApplicationContext());
        gsh.getSQLiteHistory();
    }

    sendNotification(message);

}
// [END receive_message]

/**
 * Create and show a simple notification containing the received GCM message.
 *
 * @param message GCM message received.
 */

private void sendNotification(String message) {
    Intent intent = new Intent(this, MainActivity.class);
    intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
    PendingIntent pendingIntent = PendingIntent.getActivity(this, 0 /* Request code */, intent,
            PendingIntent.FLAG_ONE_SHOT);

    Uri defaultSoundUri= RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
    NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(this)
            .setSmallIcon(R.drawable.ic_stat_ic_notification)
            .setContentTitle("my alert")
            .setContentText(message)
            .setAutoCancel(true)
            .setSound(defaultSoundUri)
            .setContentIntent(pendingIntent);

    NotificationManager notificationManager =
            (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);

    notificationManager.notify(0 /* ID of notification */, notificationBuilder.build());
}
}

public void GCMRefresh(List<RowItem> rowItems)
{
    adapter = new CustomListViewAdapter(this.getActivity(),
                R.layout.list_item, rowItems); //CRASH HERE
    mList.setAdapter(adapter);
}

public class CustomListViewAdapter extends ArrayAdapter<RowItem> {

    Context context;

    public CustomListViewAdapter(Context context, int resourceId,
                                 List<RowItem> items) {
        super(context, resourceId, items);
        this.context = context;
    }

    /*private view holder class*/
    private class ViewHolder {
        ImageView imageView;
        TextView txtTitle;
        TextView txtDesc;
    }

    public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder holder = null;
        RowItem rowItem = getItem(position);

        LayoutInflater mInflater = (LayoutInflater) context
                .getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
        if (convertView == null) {
            convertView = mInflater.inflate(R.layout.list_item, null);
            holder = new ViewHolder();
            holder.txtDesc = (TextView) convertView.findViewById(R.id.desc);
            holder.txtTitle = (TextView) convertView.findViewById(R.id.title);
            holder.imageView = (ImageView) convertView.findViewById(R.id.icon);
            convertView.setTag(holder);
        } else
            holder = (ViewHolder) convertView.getTag();

        holder.txtDesc.setText(rowItem.getDesc());
        holder.txtTitle.setText(rowItem.getTitle());
        holder.imageView.setImageResource(rowItem.getImageId());

        return convertView;
    }
}

public void GCMRefresh（列出行项目）
{
adapter=新的CustomListViewAdapter（this.getActivity（），
R.layout.list_item，rowItems）；//此处崩溃
mList.setAdapter（适配器）；
}

添加了AlertList类： 公共类AlertsList扩展片段实现OnTaskCompleted{

...
public void setContext(Context context){
    mContext = context;
}

public AlertsList getListener(){
    return this;
}

ArrayList<String> title_array = new ArrayList<String>();
ArrayList<String> notice_array = new ArrayList<String>();

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {

    setHasOptionsMenu(true);

    View v = inflater.inflate(R.layout.alerts_list, container,
            false);
   mList = (ListView) v.findViewById(R.id.list);

    DataBaseHelper myDbHelper = new DataBaseHelper(this.getContext());
    if(myDbHelper.checkDataBase()) {
        getSQLiteHistory();
    }

    return v;
}

。。。
公共void setContext（上下文）{
mContext=上下文；
}
公共警报列表getListener（）{
归还这个；
}
ArrayList title_array=新的ArrayList（）；
ArrayList notice_array=new ArrayList（）；
@凌驾
创建视图上的公共视图（布局、充气机、视图组容器、，
Bundle savedInstanceState）{
设置选项菜单（真）；
视图v=充气机。充气（R.layout.alerts\U列表，容器，
假）；
mList=（ListView）v.findViewById（R.id.list）；
DataBaseHelper myDbHelper=新的DataBaseHelper（this.getContext（））；
if（myDbHelper.checkDataBase（））{
getSQLiteHistory（）；
}
返回v；
}

CustomListViewAdapter类：

public class MyGcmListenerService extends GcmListenerService {

private static final String TAG = "MyGcmListenerService";

/**
 * Called when message is received.
 *
 * @param from SenderID of the sender.
 * @param data Data bundle containing message data as key/value pairs.
 *             For Set of keys use data.keySet().
 */
// [START receive_message]
@Override
public void onMessageReceived(String from, Bundle data) {
    String message = data.getString("m");
    Log.d(TAG, "From: " + from);
    Log.d(TAG, "Message: " + message);

    if(myDbHelper.checkDataBase()) {
        DataBaseHelper gsh = new DataBaseHelper(getApplicationContext());
        gsh.getSQLiteHistory();
    }

    sendNotification(message);

}
// [END receive_message]

/**
 * Create and show a simple notification containing the received GCM message.
 *
 * @param message GCM message received.
 */

private void sendNotification(String message) {
    Intent intent = new Intent(this, MainActivity.class);
    intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
    PendingIntent pendingIntent = PendingIntent.getActivity(this, 0 /* Request code */, intent,
            PendingIntent.FLAG_ONE_SHOT);

    Uri defaultSoundUri= RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
    NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(this)
            .setSmallIcon(R.drawable.ic_stat_ic_notification)
            .setContentTitle("my alert")
            .setContentText(message)
            .setAutoCancel(true)
            .setSound(defaultSoundUri)
            .setContentIntent(pendingIntent);

    NotificationManager notificationManager =
            (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);

    notificationManager.notify(0 /* ID of notification */, notificationBuilder.build());
}
}

public void GCMRefresh(List<RowItem> rowItems)
{
    adapter = new CustomListViewAdapter(this.getActivity(),
                R.layout.list_item, rowItems); //CRASH HERE
    mList.setAdapter(adapter);
}

public class CustomListViewAdapter extends ArrayAdapter<RowItem> {

    Context context;

    public CustomListViewAdapter(Context context, int resourceId,
                                 List<RowItem> items) {
        super(context, resourceId, items);
        this.context = context;
    }

    /*private view holder class*/
    private class ViewHolder {
        ImageView imageView;
        TextView txtTitle;
        TextView txtDesc;
    }

    public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder holder = null;
        RowItem rowItem = getItem(position);

        LayoutInflater mInflater = (LayoutInflater) context
                .getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
        if (convertView == null) {
            convertView = mInflater.inflate(R.layout.list_item, null);
            holder = new ViewHolder();
            holder.txtDesc = (TextView) convertView.findViewById(R.id.desc);
            holder.txtTitle = (TextView) convertView.findViewById(R.id.title);
            holder.imageView = (ImageView) convertView.findViewById(R.id.icon);
            convertView.setTag(holder);
        } else
            holder = (ViewHolder) convertView.getTag();

        holder.txtDesc.setText(rowItem.getDesc());
        holder.txtTitle.setText(rowItem.getTitle());
        holder.imageView.setImageResource(rowItem.getImageId());

        return convertView;
    }
}

公共类CustomListViewAdapter扩展了ArrayAdapter{
语境；
公共CustomListViewAdapter（上下文上下文，int resourceId，
（列表项目）{
超级（上下文、资源ID、项目）；
this.context=上下文；
}
/*私有视图持有者类*/
私有类视窗持有者{
图像视图图像视图；
TextView-txtTitle；
TextView-txtDesc；
}
公共视图getView（int位置、视图转换视图、视图组父视图）{
ViewHolder=null；
RowItem RowItem=getItem（位置）；
LayoutInflater mInflater=（LayoutInflater）上下文
.getSystemService（活动.布局\充气机\服务）；
if（convertView==null）{
convertView=mInflater.充气（R.layout.list_项，空）；
holder=新的ViewHolder（）；
holder.txtDesc=（TextView）convertView.findViewById（R.id.desc）；
holder.txtTitle=（TextView）convertView.findViewById（R.id.title）；
holder.imageView=（imageView）convertView.findViewById（R.id.icon）；
convertView.setTag（支架）；
}否则
holder=（ViewHolder）convertView.getTag（）；
holder.txtDesc.setText（rowItem.getDesc（））；
holder.txtitle.setText（rowItem.getTitle（））；
holder.imageView.setImageResource（rowItem.getImageId（））；
返回视图；
}
}

那么，如何更新我的listView而不使我的应用程序崩溃呢

以下是崩溃错误： 尝试在空对象引用上调用虚拟方法“java.lang.Object android.content.Context.getSystemService（java.lang.String）” 向死线程上的处理程序发送消息

谢谢

---

Eran.

感谢@Dinesh Kannan，以下是答案： CustomListViewAdapter（this.getActivity（））中的this.getActivity（）为空 在我拿到McContext后，一切都正常：

adapter = new CustomListViewAdapter(mContext,R.id.list,rowItems);

---

感谢@Dinesh Kannan，以下是答案： CustomListViewAdapter（this.getActivity（））中的this.getActivity（）为空 在我拿到McContext后，一切都正常：

adapter = new CustomListViewAdapter(mContext,R.id.list,rowItems);

---

您能发布GCM类代码吗？我认为您传递给适配器的上下文无效。getActivity（）在您的GCMRefresh（）中为空，请在定义它的地方发布一些代码。@user1992200谢谢！我发布了GCM类code@user2466914CustomListViewAdapter（this.getActivity（）中）中的this.getActivity（）为null，R.layout.list_item，rowItems）；…谢谢@user2466914，你能建议我如何获得真正的活动而不是null吗，这次，我从GCM类开始…你能发布GCM类代码吗？我想你传递给适配器的上下文无效。getActivity（）在你的GCMRefresh（）中为null，在定义它的地方发布一些代码。@user1992200谢谢！我发布了GCM类code@user2466914CustomListViewAdapter中的this.getActivity（）为空（this.getActivity（），R.layout.list_项，rowItems）；…谢谢@user2466914，你能建议我如何获得真正的活动而不是空值吗，这次，我从GCM类开始。。。