【发布时间】：2016-01-17 10:18:21
【问题描述】：
我已经使用适配器将一些图片加载到 ListView 中。当用户单击列表的任何一行时，我会在末尾显示一个复选标记：
public class LazyImageLoadAdapter extends BaseAdapter implements OnClickListener{
private Activity activity;
List<String> names,facebookbid;
String sent;
private LayoutInflater inflater=null;
public ImageLoader imageLoader;
public LazyImageLoadAdapter(Activity a, List<String> n,List<String> fid,String s) {
activity = a;
names=n;
facebookbid=fid;
sent=s;
inflater = (LayoutInflater)activity.
getSystemService(Context.LAYOUT_INFLATER_SERVICE);
imageLoader = new ImageLoader(activity.getApplicationContext(),"p");
}
@Override
public int getViewTypeCount() {
if (getCount() != 0)
return getCount();
return 1;
}
public int getCount() {
return facebookbid.size();
}
public Object getItem(int position) {
return position;
}
public long getItemId(int position) {
return position;
}
/********* Create a holder Class to contain inflated xml file elements *********/
public class ViewHolder{
public TextView text;
public ImageView image;
public ImageView checkmark;
public RelativeLayout friendsrow;
}
public View getView(final int position, View convertView, ViewGroup parent) {
convertView=null;
final ViewHolder holder;
if(convertView==null){
/****** Inflate tabitem.xml file for each row ( Defined below ) *******/
convertView = inflater.inflate(R.layout.planners_friends_listrow, null);
/****** View Holder Object to contain tabitem.xml file elements ******/
holder = new ViewHolder();
holder.text = (TextView) convertView.findViewById(R.id.planner_friend_name);
(ImageView)convertView.findViewById(R.id.planner_friend_image);
holder.checkmark=(ImageView)convertView.findViewById(R.id.checkmark);
holder.friendsrow=(RelativeLayout)convertView.findViewById(R.id.friendsrow);
/************ Set holder with LayoutInflater ************/
convertView.setTag( holder );
}
else
holder=(ViewHolder)convertView.getTag();
holder.text.setText(names.get(position));
Typeface face = Typeface.createFromAsset(convertView.getContext().getAssets(),
"fonts/MAXWELL REGULAR.ttf");
holder.text.setTypeface(face);
ImageView image = holder.image;
String link;
if(sent.equals("planners"))
{link=facebookbid.get(position);
}
else
{
link="https://graph.facebook.com/"+facebookbid.get(position)+"/picture?type=large";
}
//DisplayImage function from ImageLoader Class
imageLoader.DisplayImage(link, image);
holder.friendsrow.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
boolean a=isNetworkConnected();
if(a==true)
{
if(sender.equals("settings"))
{
}
else if(sender.equals("savethedate"))
{
if(sid.contains(facebookbid.get(position)))
{
if(sid.contains("_"))
{
sid=sid.replace("_"+facebookbid.get(position), "");
}
else
{
sid=sid.replace(facebookbid.get(position), "");
}
nb_selections--;
selectedids.remove(selectedids.size()-1);
sidetitle.setText("Invite ("+String.valueOf(nb_selections)+") friends");
holder.checkmark.setVisibility(View.GONE);
}
else
{
if(sid.isEmpty())
{
sid=sid+facebookbid.get(position);
}
else
{
sid=sid+"_"+facebookbid.get(position);
}
nb_selections++;
selectedids.add(facebookbid.get(position));
sidetitle.setText("Invite ("+String.valueOf(nb_selections)+") friends");
holder.checkmark.setVisibility(View.VISIBLE);
}
}
else
{
String friendname=names.get(position);
String friendid=facebookbid.get(position);
String friendgender=gender.get(position);
Intent resultIntent = new Intent(Friends.this,Newmarriage.class);
resultIntent.putExtra("facebookbid", friendid);
resultIntent.putExtra("name", friendname);
resultIntent.putExtra("gender", friendgender);
if(sender.equals("planner"))
{
resultIntent.putExtra("plannerid",friendid);
resultIntent.putExtra("imageurl","https://graph.facebook.com/"+friendid+"/picture?type=large");
setResult(Activity.RESULT_OK, resultIntent);
finish();
}
else
{
resultIntent.putExtra("plannerid","");
resultIntent.putExtra("imageurl","");
setResult(Activity.RESULT_OK, resultIntent);
finish();
}
}
}
else
{
Toast.makeText(getApplicationContext(),"No internet connection",Toast.LENGTH_LONG).show();
}
}
});
/******** Set Item Click Listner for LayoutInflater for each row ***********/
// vi.setOnClickListener(new OnItemClickListener(position));
return convertView;
}
@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
}
}
问题是：当 ListView 滚动时，复选标记图标就消失了。我做错了什么？
【问题讨论】：
-
我觉得很奇怪，所有项目都使用相同类型的视图渲染，
getViewTypeCount()方法返回getCount()。我希望getViewTypeCount()返回 1。 -
但是 getViewTypeCount() 返回 1 而不是 getCount() ！
-
据我所知，从您的代码（条件
if (getCount() != 0)）中可以看出，它会返回 1，以防您在facebookbid列表中没有元素。否则返回getCount()。