我有一个自定义的RecyclerView.Adapter类,我在其中实现了一个可过滤并使用接口方法覆盖,如下所示:
private MyFilter myFilter = new MyFilter(); // Class implemented below
并实施了:
@Override
public Filter getFilter() {
return myFilter;
}
这是 MyFilter 类实现:
public class MyFilter extends Filter {
@Override
protected Filter.FilterResults performFiltering(CharSequence constraint) {
FilterResults filterResult = new FilterResults();
// If the constraint is 0 return the original data
if(constraint.length() == 0) {
filterResult.values = data;
filterResult.count = data.size();
return filterResult;
}
// Method local properties used to assemble the filtered list
//String folderName;
//String cardsNumber;
//String rowId;
String tempConstraint = constraint.toString().toLowerCase();
// Iterate through the original data array
for (int i = 0; i < data.size(); i++) {
// Get the folder name from the data array
// folderName = data.get(i).familyName;
// cardsNumber = data.get(i).numOfCards;
// rowId = data.get(i).folderRowId;
// Check to see if the constraint variable corresponds to the folder name or to the
// number of cards belonging to this particular folder
if(data.get(i).familyName.toString().toLowerCase().contains(tempConstraint)) {
tempFolderRow = new FolderRow();
tempFolderRow.familyName = data.get(i).familyName;
tempFolderRow.numOfCards = data.get(i).numOfCards;
tempFolderRow.folderRowId = data.get(i).folderRowId;
// Add this object to the updated filtered list
filteredNames.add(data.get(i));
}
}
// Assign the new list to the object filterResult for return
filterResult.values = filteredNames;
filterResult.count = filteredNames.size();
return filterResult;
}
@Override
protected void publishResults(CharSequence constraint, Filter.FilterResults results) {
if(results.values != null) {
Log.e("Values: ", results.values.toString());
}
notifyDataSetChanged();
}
}
接下来,在我的活动中,我像这样实现了我的 editText 小部件:
searchView.addTextChangedListener(new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
}
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
}
@Override
public void afterTextChanged(Editable s) {
// Filter the folder adapter
mAdapterFolder.getFilter().filter(s);
}
调试我的 Filter 类(请参阅上面的代码),当它达到:
filteredNames.add(data.get(i)); // filteredNames is a List<FolderRow> obj
它返回如下所示的异常:
03-08 17:06:36.085 27853-27984/com.name.cardbox W/Filter:执行过滤()期间发生异常! java.lang.UnsupportedOperationException at java.util.AbstractList.add(AbstractList.java:404) at java.util.AbstractList.add(AbstractList.java:425) at com.birsan.cardbox.FolderAdapter$MyFilter.performFiltering(FolderAdapter.java:288) at android.widget.Filter$RequestHandler.handleMessage(Filter.java:234) at android.os.Handler.dispatchMessage(Handler.java:102) at android.os.Looper.loop(Looper.java:135) at android.os.HandlerThread.run(HandlerThread.java:61)
还有一件事,如果我注释掉发生异常的行,(filteredNames.add(data.get(i));)前面的 for 循环工作正常,所以我认为这就是问题所在。我做错了什么?
好吧,过滤器似乎不能很好地与 List<> 对象配合使用。我改变了:
筛选的名称
从
列表<文件夹行>文件夹行>
反对
数组列表<文件夹行>文件夹行>
.这让它工作了。