java - ListView 过滤器 : IllegalStateException

Question

为了理智起见，我将其发布在这里，因为我确信我现在无法自行解决。我发布了所有需要知道的东西，因为我认为为什么我过去没有解决这个问题是因为我没有发布所有内容。到目前为止，我已经剥离了代码，基本上它是尽可能轻的。但是仍然会发生此错误(尽管很少发生):

03-27 10:57:27.783: E/java.lang.IllegalStateException(4929): The content of the adapter has changed but ListView did not receive a notification. Make sure the content of your adapter is not modified from a background thread, but only from the UI thread. [in ListView(16908298, class android.widget.ListView) with Adapter(class de.innosoft.android.mobileserviceclient.activities.ListEinsaetze$ArrayAdapterEinsatz)]
03-27 10:57:27.783: E/java.lang.IllegalStateException(4929): java.lang.IllegalStateException: The content of the adapter has changed but ListView did not receive a notification. Make sure the content of your adapter is not modified from a background thread, but only from the UI thread. [in ListView(16908298, class android.widget.ListView) with Adapter(class de.innosoft.android.mobileserviceclient.activities.ListEinsaetze$ArrayAdapterEinsatz)]
03-27 10:57:27.783: E/java.lang.IllegalStateException(4929):    at android.widget.ListView.layoutChildren(ListView.java:1544)
03-27 10:57:27.783: E/java.lang.IllegalStateException(4929):    at android.widget.AbsListView.onLayout(AbsListView.java:1994)
03-27 10:57:27.783: E/java.lang.IllegalStateException(4929):    at android.widget.AdapterView.updateEmptyStatus(AdapterView.java:747)
03-27 10:57:27.783: E/java.lang.IllegalStateException(4929):    at android.widget.AdapterView.checkFocus(AdapterView.java:720)
03-27 10:57:27.783: E/java.lang.IllegalStateException(4929):    at android.widget.AdapterView$AdapterDataSetObserver.onChanged(AdapterView.java:812)
03-27 10:57:27.783: E/java.lang.IllegalStateException(4929):    at android.widget.AbsListView$AdapterDataSetObserver.onChanged(AbsListView.java:5958)
03-27 10:57:27.783: E/java.lang.IllegalStateException(4929):    at android.database.DataSetObservable.notifyChanged(DataSetObservable.java:37)
03-27 10:57:27.783: E/java.lang.IllegalStateException(4929):    at android.widget.BaseAdapter.notifyDataSetChanged(BaseAdapter.java:50)
03-27 10:57:27.783: E/java.lang.IllegalStateException(4929):    at de.innosoft.android.mobileserviceclient.ui.DynamicArrayAdapter.notifyDataSetChanged(DynamicArrayAdapter.java:291)
03-27 10:57:27.783: E/java.lang.IllegalStateException(4929):    at de.innosoft.android.mobileserviceclient.ui.DynamicArrayAdapter.notifyDataSetChanged(DynamicArrayAdapter.java:268)
03-27 10:57:27.783: E/java.lang.IllegalStateException(4929):    at de.innosoft.android.mobileserviceclient.ui.DynamicArrayAdapter$DynamicAdapterFilter.publishResults(DynamicArrayAdapter.java:119)
03-27 10:57:27.783: E/java.lang.IllegalStateException(4929):    at android.widget.Filter$ResultsHandler.handleMessage(Filter.java:282)
03-27 10:57:27.783: E/java.lang.IllegalStateException(4929):    at android.os.Handler.dispatchMessage(Handler.java:99)
03-27 10:57:27.783: E/java.lang.IllegalStateException(4929):    at android.os.Looper.loop(Looper.java:137)
03-27 10:57:27.783: E/java.lang.IllegalStateException(4929):    at android.app.ActivityThread.main(ActivityThread.java:5039)
03-27 10:57:27.783: E/java.lang.IllegalStateException(4929):    at java.lang.reflect.Method.invokeNative(Native Method)
03-27 10:57:27.783: E/java.lang.IllegalStateException(4929):    at java.lang.reflect.Method.invoke(Method.java:511)
03-27 10:57:27.783: E/java.lang.IllegalStateException(4929):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
03-27 10:57:27.783: E/java.lang.IllegalStateException(4929):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
03-27 10:57:27.783: E/java.lang.IllegalStateException(4929):    at dalvik.system.NativeStart.main(Native Method)

在这篇文章的最底部，我解释了这个错误发生的时间。但首先是代码。我有这个 TextWatcher:

edSearch.addTextChangedListener(new TextWatcher() {
                @Override
                public void onTextChanged(CharSequence s, int start, int before, int count) {
                }

                String text = null;

                @Override
                public void beforeTextChanged(CharSequence s, int start, int count, int after) {
                    text = s.toString();
                }

                @Override
                public void afterTextChanged(final Editable s) {
                    if (text != null && !text.equals(s.toString())) {
                        adapter.getFilter().filter(s.toString());
                    }
                    text = null;
                }
            });

该线程在副线运行，每 200 毫秒触发一次文本观察器。手动测试这个我会很疯狂:

new Thread(new Runnable() {
            public void run() {
                Runnable r = new Runnable() {
                    public void run() {
                         dispatchKeyEvent(new KeyEvent(KeyEvent.ACTION_DOWN,
                         KeyEvent.KEYCODE_S));
                         dispatchKeyEvent(new KeyEvent(KeyEvent.ACTION_UP,
                         KeyEvent.KEYCODE_S));
                    }
                };

                Runnable r2 = new Runnable() {
                    public void run() {
                         dispatchKeyEvent(new KeyEvent(KeyEvent.ACTION_DOWN,
                         KeyEvent.KEYCODE_DEL));
                         dispatchKeyEvent(new KeyEvent(KeyEvent.ACTION_UP,
                         KeyEvent.KEYCODE_DEL));
                    }
                };
                while (true) {

                    runOnUiThread(r);
                    try {
                        Thread.sleep(200);
                    } catch (InterruptedException e) {
                        ExceptionHandler.handle(e);
                    }
                    runOnUiThread(r2);
                    try {
                        Thread.sleep(200);
                    } catch (InterruptedException e) {
                        ExceptionHandler.handle(e);
                    }
                }
            }
        }).start();
    }

这是我的适配器:

private class ArrayAdapterEinsatz extends DynamicArrayAdapter<Einsatz> {

        public ArrayAdapterEinsatz(int textViewResourceId) {
            super(ListEinsaetze.this, textViewResourceId, new ArrayList<Einsatz>());
        }

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

            Einsatz einsatz = getFilteredItems().get(position);

            View rowView = convertView;
            if (rowView == null) {
                LayoutInflater inflater = ListEinsaetze.this.getLayoutInflater();
                rowView = inflater.inflate(R.layout.eintrag_einsatz, null);
                ViewHolder viewHolder = new ViewHolder();

                viewHolder.tvId = (TextView) rowView.findViewById(R.id.eeinsatzid);
                viewHolder.tvDatumVonbis = (TextView) rowView.findViewById(R.id.eeinsatzvonbis);
                viewHolder.tvKundenName = (TextView) rowView.findViewById(R.id.eeinsatzkundenname);
                viewHolder.tvKundenOrt = (TextView) rowView.findViewById(R.id.eeinsatzort);
                viewHolder.tvEntfernung = (TextView) rowView.findViewById(R.id.eeinsatzentfernung);
                viewHolder.iveRotate = (ImageViewEffects) rowView.findViewById(R.id.eeinsatzrotate);
                viewHolder.iveRotate.setBitmap(Utils.drawableToBitmap(R.drawable.ic_refresh_1, 22), ImageViewEffects.ROTATE);
                viewHolder.ivAnsprechpartnerVorhanden = (ImageView) rowView.findViewById(R.id.eeinsatzimageansprechvorhanden);
                viewHolder.ivBelegeVorhanden = (ImageView) rowView.findViewById(R.id.eeinsatzimagebelegevorhanden);
                viewHolder.ivTaetigkeitVorhanden = (ImageView) rowView.findViewById(R.id.eeinsatzimagetaetigkeitvorhanden);

                rowView.setTag(viewHolder);
            }

            final ViewHolder holder = (ViewHolder) rowView.getTag();

            return rowView;
        }

    }

最后，这是基础适配器类。请注意最底部的实际过滤功能，它根据 new Random().nextBoolean() 进行过滤，这再简单不过了。

public class DynamicArrayAdapter<T> extends BaseAdapter implements Filterable {

  public class DynamicAdapterFilter extends Filter {

    private CharSequence m_Filter = null;
    private List<T> m_FilteredItems = null;

    public DynamicAdapterFilter() {
      m_FilteredItems = new ArrayList<T>();
    }

    @Override
    protected FilterResults performFiltering(CharSequence constraint) {


      FilterResults r = new FilterResults();
      List<T> items = null;
      m_Filter = constraint;

      if (constraint == null) {
        items = m_AllItems;
      } else {
        items = m_FilteredItems;
        items.clear();

        synchronized (SyncLock) {
          List<T> l = new ArrayList<T>(m_AllItems);
          for (T item : l) {
            if (DynamicArrayAdapter.this.filter(item, constraint)) {
              items.add(item);
            }
          }
        }
      }

      r.values = items;
      r.count = items.size();

      return r;
    }

    @SuppressWarnings("unchecked")
    @Override
    protected void publishResults(CharSequence constraint, FilterResults results) {

      m_Items = (List<T>) results.values;

      notifyDataSetChanged();

    }

    public void refresh() {
      if (m_Filter != null) {

        filter(m_Filter);
      }
    }

    public void refresh(FilterListener listener) {
      if (m_Filter != null ) {

        filter(m_Filter, listener);
      }
    }
  }


  private final Object SyncLock = new Object();
  private Context m_Context = null;
  private LayoutInflater m_Inflater = null;
  private int m_DelegateResourceId;
  private boolean m_ChangeNotificationsEnabled = true;
  private List<T> m_AllItems = null;
  private List<T> m_Items = null;
  private DynamicAdapterFilter m_Filter = null;


  public DynamicArrayAdapter(Context context, int delegateResourceId) {
    this(context, delegateResourceId, new ArrayList<T>());
  }

  public DynamicArrayAdapter(Context context, int delegateResourceId, List<T> items) {
    m_Context = context;
    m_DelegateResourceId = delegateResourceId;
    initItems(items);

    m_Inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

  }

  public void initItems(List<T> items) {
    m_AllItems = m_Items = items;
  }

  /**
   * returns the filtered item count (or all item count if no filter exists)
   */
  @Override
  public int getCount() {
        return m_Items != null ? m_Items.size() : 0;
  }

  /**
   * returns the item at the position in the filtered list (or all item count if
   * no filter exists)
   */
  @Override
  public T getItem(int position) {
    return m_Items.get(position);
  }

  /**
   * holt position von item, exakte gleiche implementation wie ArrayAdapter<T>
   * 
   * @param item
   * @return
   */
  public int getPosition(T item) {
    return m_Items.indexOf(item);
  }

  /**
   * {@inheritDoc}
   */
  @Override
  public long getItemId(int position) {

    return position;
  }

  /**
   * returns the list view item delegate view. this view is inflated if it isn't
   * already inflated. Override this method to perform custom view operations
   * for the list view item.
   */
  @Override
  public View getView(int position, View convertView, ViewGroup parent) {
    if (convertView == null) {
      convertView = m_Inflater.inflate(m_DelegateResourceId, parent, false);
    }

    return convertView;
  }

  /**
   * returns the filter. this filter is created if it hasn't yet been created.
   */
  @Override
  public DynamicAdapterFilter getFilter() {
    if (m_Filter == null) {
      m_Filter = new DynamicAdapterFilter();
    }

    return m_Filter;
  }

  /**
   * If notifications are enabled, this notifies the base adapter that the
   * backing data has changed
   */
  @Override
  public void notifyDataSetChanged() {
    notifyDataSetChanged(false);
  }

  /**
   * If forced or notifications are enabled, this notifies the base adapter that
   * the backing data has changed
   * 
   * @param force
   *          force notify even if notifications are disabled
   */
  public void notifyDataSetChanged(boolean force) {
    if (force || m_ChangeNotificationsEnabled) {

      super.notifyDataSetChanged();
    }
  }

  /**
   * @return UI context
   */
  public Context getContext() {
    return m_Context;
  }

  /**
   * @return UI inflater
   */
  public LayoutInflater getLayoutInflater() {
    return m_Inflater;
  }

  /**
   * @return Layout ID of the list view item delegate
   */
  public int getDelegateResourceId() {
    return m_DelegateResourceId;
  }

  /**
   * @return true if notifications are enabled, false otherwise
   */
  public boolean getChangeNotificationsEnabled() {
    return m_ChangeNotificationsEnabled;
  }

  /**
   * Set whether notifications are enabled or not
   */
  public void setChangeNotificationsEnabled(boolean value) {
    m_ChangeNotificationsEnabled = value;
  }

  // internal mechanism to handle automagical updates of the list items
  private void onDataChange() {


    if (m_Filter == null) {
      notifyDataSetChanged();
    } else {
      m_Filter.refresh();
    }
  }

  /**
   * @return All (unfiltered) items
   */
  public List<T> getAllItems() {
    return m_AllItems;
  }

  /**
   * Set the backing list
   */
  public void setAllItems(List<T> value) {
    m_AllItems = value;

    onDataChange();
  }

  /**
   * @return Current filtered items, or all items if there is no filter
   */
  public List<T> getFilteredItems() {
    return m_Items;
  }

  public void add(T item) {
    synchronized (SyncLock) {
      m_AllItems.add(item);
    }

    onDataChange();
  }

  public void insert(T item, int index) {
    synchronized (SyncLock) {
      m_AllItems.add(index, item);
    }

    onDataChange();
  }

  public void remove(T item) {
    synchronized (SyncLock) {
      m_AllItems.remove(item);
    }

    onDataChange();
  }

  public void removeAt(int index) {
    synchronized (SyncLock) {
      m_AllItems.remove(index);
    }

    onDataChange();
  }

  public void clear() {
    synchronized (SyncLock) {
      m_AllItems.clear();
    }

    onDataChange();
  }

  public void sort(Comparator<? super T> comparator) {
    synchronized (SyncLock) {
      Collections.sort(m_Items, comparator);
    }

    onDataChange();
  }

  protected boolean filter(T item, CharSequence constraint) { // AR
    return new Random().nextBoolean();

  }
}

所以基本上程序只是每 200 毫秒触发一次 textwatcher。所以 textwatcher 一次又一次地过滤列表。程序中没有其他快乐。

如果我没有设置断点，程序就可以正常运行，永远不会出错。

断点时出现错误

adapter.getFilter().filter(s.toString());

在 TextWatcher 中按住 F8(继续)(这似乎会给程序流程带来不规则性，我只能想象？)。没有断点就不会出错。

顺便说一句，如果我放

adapter.notifyDatasetChanged()

之后

adapter.getFilter().filter(s.toString());

同样的错误将在 100% 的时间内发生(我知道在 publishResults 中调用了 notifyDatasetChanged，所以我不不需要它，但它仍然是正确的行为吗？)。

长话短说:

我的代码(尤其是基本适配器代码)是故障安全的吗？ (否则不会发生任何错误)

编辑:

当没有设置断点时也会发生错误我刚得到一个...

Answer 1

试着移动你的

 adapter.getFilter().filter(s.toString());

在 runnable 中使用 view.post() 进入 ui 线程。

它“可能”解决您的问题。