在Android上滚动时,列表视图位置正在逐渐改变 [英] list view position is getting changed when scrolling on android

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问题描述

我的列表视图[文本视图和复选框controlls]有更多的数据。我会选择从列表视图中的项目,并显示在接下来的活动中选定的项目。 我的问题是,对于例如,如果我选择20日和25日的项目列表中查看它会显示下一个活动的一些其他物品。 这就是滚动时,列表视图位置正在逐渐改变。

我按一下该项目的复选框,选择一个项目。在checkbox.setOnChanged监听我写的哪个位置是否选择code。如果让我选择25号项目,滚动列表视图中,getview方法被调用,checkbox.setonChanged方法是改变选择的位置。我打印logcat的最后。

我的编码格式:

 公共类ListContact扩展ListActivity {
  公共无效的onCreate(包冰柱){
    .....
    ArrayAdapter<型号:GT;适配器=新MyCustomArrayAdapter(这一点,getModel());
    setListAdapter(适配器);
  }
 ....
私人列表<型号:GT; getModel(){
    名单<型号:GT;名单=新的ArrayList<型号>();

迭代器<字符串> ITR = constant.selectname.iterator();
    而(itr.hasNext()){
        list.add(得到(itr.next()的toString()));
    }
    返回列表;
}

私模的get(String s)将{
    返回新模式(S);
}

}
 

MyCustomArrayAdapter.java:

 公共类MyCustomArrayAdapter扩展ArrayAdapter<型号:GT; {

    私人最终名单,其中,型号>清单;
    私人最终活动范围内;
    恒CON;
    公共MyCustomArrayAdapter(活动背景下,列表与LT;型号>列表){
        超(背景下,R.layout.list_layout,清单);
        this.context =背景;
        this.list =清单;
    }

    静态类ViewHolder {
        受保护的TextView文本;
        保护复选框复选框;
    }

    @覆盖
    公共查看getView(最终诠释的立场,观点convertView,ViewGroup中父){

// Log.e(getview,getview);
        查看查看= NULL;
        如果(convertView == NULL){
            LayoutInflater充气= context.getLayoutInflater();
            鉴于= inflator.inflate(R.layout.list_layout,NULL);
            最后ViewHolder viewHolder =新ViewHolder();
            viewHolder.text =(TextView中)view.findViewById(R.id.label);
            viewHolder.checkbox =(复选框)view.findViewById(R.id.check);
            viewHolder.checkbox.setOnCheckedChangeListener(新CompoundButton.OnCheckedChangeListener(){
                        公共无效onCheckedChanged(CompoundButton buttonView,布尔器isChecked){
// CON =新常数();
                            模型元素=(模型)viewHolder.checkbox.getTag();
                            element.setSelected(buttonView.isChecked());
// Log.e(MyCustomArrayAdapter.java,selectpos数组列表长度+ constant.selectpos.size());
                            如果(==器isChecked真){
                                Log.e(复选框价值与地位,element.getName());
                                Log.e(位置,+位置);
                                con.selectpos.set(位置,1);

                            }
                            其他{
                                Log.e(位置取消选择,+位置+---------+ element.getName());
                                con.selectpos.set(位置,0);
                            }
                        }
                    });
            view.setTag(viewHolder);
            viewHolder.checkbox.setTag(list.get(位置));
        } 其他 {
            鉴于= convertView;
            ((ViewHolder)view.getTag())checkbox.setTag(list.get(位置))。
        }
        ViewHolder支架=(ViewHolder)view.getTag();
        holder.text.setText(list.get(位置).getName());
        holder.checkbox.setChecked(list.get(位置).isSelected());
        返回查看;
    }
}
 

logcat的结果:

  10月2号至八号:44:28.142:E /复选框值和位置(293):AAAA QQQ
十月2日至8日:44:28.142:E /复选框值和位置(293):移动-123
十月2日至8日:44:28.152:E /位置(293):0

**滚动列表中查看其他项目打印第0位选择,而错误的数据后:**
十月2日至8日:44:31.962:E /位置取消选择(293):0 --------- F212
十月2日至8日:44:31.962:E /位置取消选择(293):主页-232
 

解决方案

我解决了这个问题。我添加了

 查看视图= NULL;
  convertView = NULL;在get观点和意见的其他部分
        如果(convertView == NULL){
                }
                /*其他{
                } * /
 

I have list view [text view and check box controlls] with more data. I will choose the item from list view and display the selected items in the next activity. My problem is, for the example if I choose 20th and 25th item in the list view it will display some other items in the next activity. That is list view position is getting changed when scrolling.

i am choosing an item by clicking the check box on the item. in the checkbox.setOnChanged listener i wrote code for which position is selected or not. if i choose 25th item and scroll the list view, the getview method is called and the checkbox.setonChanged method is change the selected position. I print the logcat at last.

My coding format:

public class ListContact extends ListActivity {
  public void onCreate(Bundle icicle){
    .....
    ArrayAdapter<Model> adapter = new MyCustomArrayAdapter(this,getModel());
    setListAdapter(adapter);
  }
 ....
private List<Model> getModel() {
    List<Model> list = new ArrayList<Model>();

Iterator<String> itr = constant.selectname.iterator();
    while (itr.hasNext()) {
        list.add(get(itr.next().toString()));
    }
    return list;
}

private Model get(String s) {
    return new Model(s);
}  

}

MyCustomArrayAdapter.java:

public class MyCustomArrayAdapter extends ArrayAdapter<Model> {

    private final List<Model> list;
    private final Activity context;
    constant con ;
    public MyCustomArrayAdapter(Activity context, List<Model> list) {
        super(context, R.layout.list_layout, list);
        this.context = context;
        this.list = list;
    }

    static class ViewHolder {
        protected TextView text;
        protected CheckBox checkbox;
    }

    @Override
    public View getView(final int position, View convertView, ViewGroup parent) {

//      Log.e("getview", "getview");
        View view = null;
        if (convertView == null) {
            LayoutInflater inflator = context.getLayoutInflater();
            view = inflator.inflate(R.layout.list_layout, null);
            final ViewHolder viewHolder = new ViewHolder();
            viewHolder.text = (TextView) view.findViewById(R.id.label);
            viewHolder.checkbox = (CheckBox) view.findViewById(R.id.check);
            viewHolder.checkbox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
                        public void onCheckedChanged(CompoundButton buttonView,boolean isChecked) {
//                          con = new constant();
                            Model element = (Model) viewHolder.checkbox.getTag();
                            element.setSelected(buttonView.isChecked());
//                          Log.e("MyCustomArrayAdapter.java", "selectpos array list length"+constant.selectpos.size());
                            if(isChecked==true){
                                Log.e("check box value and position  ", element.getName());
                                Log.e("position", ""+position);
                                con.selectpos.set(position, 1);

                            }
                            else{
                                Log.e("position unselect", ""+position +"---------"+ element.getName());
                                con.selectpos.set(position, 0);
                            }
                        }
                    });
            view.setTag(viewHolder);
            viewHolder.checkbox.setTag(list.get(position));
        } else {
            view = convertView;
            ((ViewHolder) view.getTag()).checkbox.setTag(list.get(position));
        }
        ViewHolder holder = (ViewHolder) view.getTag();
        holder.text.setText(list.get(position).getName());
        holder.checkbox.setChecked(list.get(position).isSelected());
        return view;
    }
}

logcat result:

02-08 10:44:28.142: E/check box value and position(293): AAAA  Qqq 
02-08 10:44:28.142: E/check box value and position(293): Mobile-123
02-08 10:44:28.152: E/position(293): 0

**after scrolling the list view some other item print 0th position unselected and wrong data:**
02-08 10:44:31.962: E/position unselect(293): 0---------F212
02-08 10:44:31.962: E/position unselect(293): Home-232

解决方案

I solved the problem. i add the

  View view = null;
  convertView = null;  in the get view and comments the else part of
        if (convertView == null) {
                }
                /*else{
                } */

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