如何讓ListView在單擊onClickListener後正確顯示？

Question

更新： 我已決定使用ExpandableListAdapter來完成此操作...因爲此代碼幾乎是有效地嘗試工程師可擴展的listadapter已經做了什麼。

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爲了讓ListView的簡單工作我使用ViewHolder的標準模式......

 
public View getView(int position, View convertView, ViewGroup parent) { 
    View vi=convertView; 
    ViewHolder holder; 
    if(convertView == null){ 
      vi = inflater.inflate(R.layout.item, null); 
      holder=new ViewHolder(); 
      holder.text=(TextView)vi.findViewById(R.id.text); 
      holder.image=(ImageView)vi.findViewById(R.id.image); 
      holder.expandButton=(ImageView)vi.findViewById(R.id.expand_button); 
      vi.setTag(holder); 
     } 
     else 
      holder=(ViewHolder)vi.getTag(); 

However....I believe that inside of my onClickListener...something is going wrong.

 
final String textData = texts[position]; 
final ViewHolder holderFinal = holder; 
holder.expandButton.setVisibility(View.VISIBLE); 
holder.expandButton.setOnClickListener(new View.OnClickListener() 
    @Override 
    public void onClick(View v) { 
    holderFinal.expandButton.setImageResource(R.drawable.expander_ic_maximized); 
    holderFinal.text.setText(textData); 

So, everything displays fine when scrolling back and forth....however, whenever one of the listitems is expanded, the final line above contains a textData that belongs to another row. How do I get the correct textData to work INSIDE the onCLick listener?

Answer 1

i was experimented the same issue, i resolve this problem doing each item object of the listview a static class, like this:

all the data necesary to display a row in the ListView i defined in a static class like this:

static class DataHolder{ 
     Drawable extIcon; 
     String text; 
     String quantity_text; 
     Drawable icon; 
     int progressBarVisible; 
     int quantityTextVisible; 
    } 

then to create all rows i make this:

ArrayList<DataHolder> data = new ArrayList<DataHolder>(); 
      for (int i=0 ; i < activitys.length ; i++) { 
       DataHolder item = new DataHolder(); 
    item.icon = icons[i]; //an icons array 
       item.quantity_text = ""; //some text 
       item.progressBarVisible = View.GONE; //a status for a progress bar 
//other data setting 
    } 

then my ArrayAdapter subclass:

class ActivityList extends ArrayAdapter<DataHolder>{ 

     public ActivityList(Context context, int textViewResourceId, ArrayList<DataHolder> objects) { 
      super(context, textViewResourceId, objects); 
     } 

     @Override 
     public View getView(int position, View convertView, ViewGroup parent) { 
      ViewHolder holder; 
      if(convertView == null){ 
       LayoutInflater inflater = LayoutInflater.from(HomeActivity.this); 
       convertView = inflater.inflate(R.layout.home_activity_item, parent, false); 
       holder = new ViewHolder(); 

       holder.text = (TextView)convertView.findViewById(R.id.homeActivityText); 
       holder.icon = (ImageView)convertView.findViewById(R.id.homeActivityIcon); 
       holder.progressBar = (ProgressBar)convertView.findViewById(R.id.homeActivityQuantityPBar); 
       holder.quantity_text = (TextView)convertView.findViewById(R.id.homeActivityQuantity); 
       holder.extIcon = (ImageView)convertView.findViewById(R.id.homeActivityIconExtended); 

       convertView.setTag(holder); 
      }else{ 
       holder = (ViewHolder) convertView.getTag(); 
      } 

      holder.text.setText(getItem(position).text); 
      holder.icon.setImageDrawable(getItem(position).icon); 
      holder.quantity_text.setVisibility(getItem(position).quantityTextVisible); 
      holder.quantity_text.setText(getItem(position).quantity_text); 
      holder.progressBar.setVisibility(getItem(position).progressBarVisible ); 
      holder.extIcon.setImageDrawable(getItem(position).extIcon); 
      return convertView; 
     } 

    } 

finally i dont have a button on my list row view but i can do any operation on various context in this way, obtaining always the exact text. (the listView field is the instance of ActivityList) (SAVED_SEARCH is the list item position)

((ActivityList)listView.getAdapter()).getItem(SAVED_SEARCHED).progressBarVisible = View.GONE; 
((ActivityList)listView.getAdapter()).getItem(SAVED_SEARCHED).quantity_text = "any text"; 
((ActivityList)listView.getAdapter()).notifyDataSetChanged(); 

sincerally hope this help you.

Answer 2

Try postInvalidate()ing the ViewHolder after click.

Answer 3

Hi look at my solution on a similar problem:

• Change ListView background - strange behaviour
  I'm using there the holder pattern too

Answer 4

initialize int GlobalPostion as a global variable

GlobalPosition = position
holder.expandButton.setOnClickListener(new View.OnClickListener() int localPosition = GlobalPosition @Override public void onClick(View v) {
holderFinal.expandButton.setImageResource(R.drawable.expander_ic_maximized); holderFinal.text.setText(""+texts[localPosition]); }

的問題是你沒有得到確切的列表中的位置，如果你存儲它在全局變量中，然後移動到OnClick中的局部變量，您可以保留該位置。 我希望這會幫助你