问题描述
我一直在研究这个问题，找不到解决方案.关于我的自定义列表视图的所有内容似乎都能正常执行.当我单击holder.feedUpVoteButton时，文本正确更改了+=1.但是，当我向下滚动并向上滚动时，文本值将还原为单击之前的值.
I've been researching this forever and can't find a solution. Everything about my custom list view seems to perform correctly. When I click on the holder.feedUpVoteButton, the text changes +=1 correctly. However, when I scroll down and scroll back up, the text value is reverted to the value it had before it was clicked.
我拒绝使用notifyDatasetChanged，因为我没有添加任何东西或从列表中删除任何东西.
I refuse to use notifyDatasetChanged because I am not adding anything or removing anything from the list.
public class CustomFeedListViewAdapter extends BaseAdapter{
CustomFeedListViewAdapter customFeedListViewAdapter;
Date createdAt, currentDate; int num;
static HashMap<String, String> oneData = new HashMap<String, String>();
HashMap<String, String> iFeed = new HashMap<>();
private String likesString;
String upVoteClicked, downVoteClicked;
HashMap<String, String> mFeed = new HashMap<>();
List<ParseObject> mObjects;
private ParseObject parseObFeed;
CustomFeedListViewAdapter(Context context, ArrayList<HashMap<String, String>> data) {
super();
this.mContext = context;
GlobalFeedTab.arrayFeedList = data;
inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}
@Override
public int getCount() {
return GlobalFeedTab.arrayFeedList.size();
}
@Override
public Object getItem(int i) {
return GlobalFeedTab.arrayFeedList.get(i);
}
@Override
public long getItemId(int i) {
return i;
}
@Override
public View getView(int i, View view, ViewGroup viewGroup) {
likes = new int[GlobalFeedTab.arrayFeedList.size()];
countryNames = new int[GlobalFeedTab.arrayFeedList.size()];
dateNames = new String[GlobalFeedTab.arrayFeedList.size()];
final ViewHolder holder;
if (view == null) {
position = i;
view = inflater.inflate(R.layout.feed_list_row, viewGroup, false);
holder = new ViewHolder();
holder.feedNumOfLikes = (TextView) view.findViewById(R.id.feedNumofLikes);
holder.feedUpVoteButton = (Button) view.findViewById(R.id.feedUpVoteButton);
} else {
position = i;
holder = (ViewHolder) view.getTag();
}
mFeed = GlobalFeedTab.arrayFeedList.get(position);
holder.feedNumOfLikes.setText(mFeed.get("likes"));
likesString = mFeed.get("likes");
likes[position] = Integer.valueOf(likesString);
holder.feedUpVoteButton.setTag(position);
ParseQuery<ParseObject> query2 = new ParseQuery<ParseObject>("FeedItem");
query2.setLimit(250);
query2.addDescendingOrder("createdAt");
query2.findInBackground(new FindCallback<ParseObject>() {
@Override
public void done(final List<ParseObject> objects, ParseException e) {
if (e == null) {
for ( final ParseObject object : objects) {
holder.feedUpVoteButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
int pos = (Integer) v.getTag();
parseObFeed = objects.get(pos);
username = parseObFeed.getString("username");
createdAt = parseObFeed.getDate("createdAt");
likes[pos] += 1;
parseObFeed.put("likes", likes[pos]);
holder.feedNumOfLikes.setText(String.valueOf(parseObFeed.getInt("likes")));
parseObFeed.put(ParseUser.getCurrentUser().getUsername() + "upvoteClicked", true);
parseObFeed.saveInBackground();
}
});
}
});
return view;
}
private class ViewHolder {
ImageView feedProfilePic;
TextView feedUsername;
TextView feedNumOfLikes;
TextView feedFeedItem;
TextView feedDate;
TextView feedNumofReplies;
Button feedUpVoteButton;
Button feedDownVoteButton;
Button feedCommentButton;
ListView feedListView;
}
}
推荐答案
经过不断的反复试验.我终于想出了滚动后如何更改textview的方法.我的问题是我得到了错误的ParseObject值.我的主要活动包含ParseQuery，而我是从Hashmap();获取likes的.但是，由于某种原因，我无法直接传递Likes的值，因此我传递了ParseObject本身.因此，不需要在我的BaseAdapter类中进行查询.然后，我在GetView();中实现了以下几行代码，以回答我的原始问题:
After continuous trial and error. I finally figured out how to change a textview after it scrolls. My problem was I was getting the wrong ParseObject value. My main activity contains a ParseQuery and I was getting the likesfrom a Hashmap(); However, for some reason I couldn't pass the value of likes directly so I passed the ParseObject itself. Therefore, needing no query in my BaseAdapter Class. Then, I implemented these lines of code in GetView(); to answer my original question:
holder.upvote[position] = holder.parseObList[position].getBoolean(ParseUser.getCurrentUser().getUsername() + "upvoteClicked");
holder.downvote[position] = holder.parseObList[position].getBoolean(ParseUser.getCurrentUser().getUsername() + "downvoteClicked");
if(holder.upvote[position] ){
holder.feedUpVoteButton.setBackgroundResource(R.drawable.arrowclicked);
holder.feedNumOfLikes.setText(String.valueOf(holder.likes[position]));
}
else if(!holder.upvote[position]){
holder.feedUpVoteButton.setBackgroundResource(R.drawable.arrowunclicked);
holder.feedNumOfLikes.setText(String.valueOf(holder.likes[position]));
}
if(holder.downvote[position]){
holder.feedDownVoteButton.setBackgroundResource(R.drawable.arrowclicked);
}
else if(!holder.downvote[position]){
holder.feedDownVoteButton.setBackgroundResource(R.drawable.arrowunclicked);
}
这篇关于在基本适配器中滚动后，TextView值变回先前的值的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！