android - 当我单击 ListView 中的小部件时，如何使用 ResourceCursorAdapter 获取 View 项

Question

我有几天以来一直困扰着我的这个特殊问题。我使用了搜索但找不到任何对我的问题有帮助的文章。我想这也是我搜索的问题。然而，回到我的问题。

我使用 ResourceCursorAdapter 来填充我的 ListView。
我的 ListView 项目看起来像..

    <?xml version="1.0" encoding="utf-8"?>
    <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content" >

        <TextView
            android:id="@+id/title_tv"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content" />
        <TextView
            android:id="@+id/description_tv"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content" />
        <CheckBox
            android:id="@+id/download_cb"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content" />
        <Button
            android:id="@+id/some_bt"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content" />
        <ImageButton
            android:id="@+id/pdf_ib"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content" />
        <ProgressBar
            android:id="@+id/download_pb"
            style="?android:attr/progressBarStyleHorizontal"
            android:layout_width="fill_parent"
            android:layout_height="10dip" />
    </RelativeLayout>       

我的适配器:

private final class ListAdapter extends ResourceCursorAdapter implements
        DownloadCallback, OnItemClickListener, OnClickListener {

            public ListAdapter(Context context, int layout, Cursor c) {
        super(context, layout, c);
    }

    @Override
    public void bindView(View view, Context context, Cursor cursor) {
        final ItemHolder holder = (ItemHolder) view.getTag();

        holder.url = cursor.getString(..);

        holder.titleTv.setText(cursor.getString(..));
        holder.descriptionTv.setText(cursor.getString(..));
        ...

        if(cursor.getInt(..) == 1) {
            holder.progress.setVisible(View.GONE);          
        }

        if(cursor.getInt(...) == 1) {
            holder.downloadCb.setEnabled(isConnectedToNet); 
        }
    }

    @Override
    public View newView(Context context, Cursor cursor, ViewGroup parent) {
        View view = super.newView(context, cursor, parent);
        ItemHolder holder = new ItemHolder();

        view.setOnClickListener(this);

        holder.titleTv = (TextView) view.findViewById(R.id.title_tv);
        holder.descriptionTv = (TextView) view.findViewById(R.id.description_tv);
        ...

        holder.downloadCb.setEnabled(isConnectedToNet);                 
        holder.downloadCb.setOnClickListener(this);         
        holder.downloadCb.setOnCheckedChangeListener(new OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {                    
                prepare2Download();

                DownItem di = new DownItem();
                di.url = holder.url;        /// <========= to do this               

                // start async downloader and notify progressbar "holder.downPb"                    
                Download serverTaskObject = new Download();                 
                serverTaskObject.execute(currDownholder.copy());    

                holder.downPb.setVisibility(View.GONE);     // <======== and this.          
            }
        });

        holder.pdfIb = (ImageButton) view.findViewById(R.id.pdf_ib);
        holder.pdfIb.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                // start new activity and load website.
                openUrl(holder.url);    // <============ or this.
            }
        });

        holder.downPb = (ProgressBar) view.findViewById(R.id.pb_law_download);
        holder.downPb.setVisibility(View.GONE);

        view.setTag(cachedItem);
        return view;
    }

    ...

    private static class LawItemCache {
        TextView titleTv;
        TextView descriptionTv;
        ...

        CheckBox downloadCb;
        ImageButton pdfIb;

        ProgressBar downPb;

        String url;
        IProgressListener listener;
    }
}

我的问题是..当我单击 ListView 中的 Button 或 Checkbox 时，我想在特定的 View holder 中进行一些更改，例如使 Progressbar 可见或消失。我还不知道如何在我的适配器中获取 View holder 以进行更改。

我希望我解释得足够好，能够切入我的问题所在。

Answer 1

我为此苦苦挣扎，终于成功了!我的行中有一个复选框，并且正在使用 ResourceCursorAdapter。诀窍是意识到复选框单击处理程序需要在 getView() 或 newView() 中绑定(bind)，而 holder 需要在 bindView() 中关联。这样，ListView 中当前显示的行始终具有正确的持有人信息。这是我的 bindView 和 getView 方法:

 public void bindView(View view, Context context, Cursor cursor) {
                Log.i(CN,"bindView");
                TextView todoTxt = (TextView)view.findViewById(R.id.todoItemText);
                Log.i(CN,"bindView set txt");
                TextView todoTitle = (TextView)view.findViewById(R.id.todoItemTitle);
                Log.i(CN,"bindView set title");
                CheckBox cBox = (CheckBox)view.findViewById(R.id.todoChecked);
                Log.i(CN,"bindView set check");

                IOweRowTag tag=(IOweRowTag)cBox.getTag();
                int pos=cursor.getInt(cursor.getColumnIndex(Todos._ID));
                Log.i(CN,"getView: no tag on "+pos);
                tag=new IOweRowTag();
                tag.id=pos;
                cBox.setTag(tag);

//              IOweRowTag irt=(IOweRowTag)view.getTag();
//              if(irt!=null)
//                  Log.i(CN,"Got irt id="+irt.id);
//              else
//                  Log.i(CN,"No id");
//              
                Log.i(CN,"got title="+cursor.getString(cursor.getColumnIndex(Todos.TITLE)));
                Log.i(CN,"got txt="+cursor.getString(cursor.getColumnIndex(Todos.TEXT)));

                todoTitle.setText(cursor.getString(cursor.getColumnIndex(Todos.TITLE)));
                todoTxt.setText(cursor.getString(cursor.getColumnIndex(Todos.TEXT)));
                cBox.setChecked(true);

            }




        public View getView (int position, View convertView, ViewGroup parent) {
            View tmpView=super.getView(position, convertView, parent);
            Log.i(CN,"getView:"+position);
            final CheckBox cBox = (CheckBox) tmpView.findViewById(R.id.todoChecked);
            IOweRowTag tag=(IOweRowTag)cBox.getTag();
            cBox.setOnClickListener(new OnClickListener() { 

                public void onClick(View v) { 
                    IOweRowTag tag=(IOweRowTag)v.getTag();
                    if(tag==null)
                        Log.i(CN,"checkbox clicked no tag");
                    else
                        Log.i(CN,"checkbox clicked tag="+tag.id);
                   if(cBox.isChecked()) { 
                       Log.i(CN," Checked!"); 
                       // do some operations here 
                   }   
                   else{ 
                       Log.i(CN,"NOT Checked!"); 
                       // do some operations here 
                   }
               }
                });


            return tmpView;
        }

希望对你有帮助!