列表视图包含自定义适配器复选框 [英] Listview with custom adapter containing CheckBoxes

问题描述

我有一个ListView，它使用如自定义适配器：

I have a ListView which uses a custom adapter as shown:

private class CBAdapter extends BaseAdapter implements OnCheckedChangeListener{

    Context context;
    public String[] englishNames;
    LayoutInflater inflater;
    CheckBox[] checkBoxArray;
    LinearLayout[] viewArray;
    private boolean[] checked;

    public CBAdapter(Context con, String[] engNames){
        context=con;
        englishNames=engNames;
        inflater=(LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        checked= new boolean[englishNames.length];
        for(int i=0; i<checked.length; i++){
            checked[i]=false;
            //Toast.makeText(con, checked.toString(),Toast.LENGTH_SHORT).show();
        }
        checkBoxArray = new CheckBox[checked.length];
        viewArray = new LinearLayout[checked.length];
    }

    public int getCount() {
        return englishNames.length;
    }

    public Object getItem(int position) {
        // TODO Auto-generated method stub
        return null;
    }

    public long getItemId(int position) {
        // TODO Auto-generated method stub
        return 0;
    }

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

        if(viewArray[position] == null){

            viewArray[position]=(LinearLayout)inflater.inflate(R.layout.record_view_start,null);

            TextView tv=(TextView)viewArray[position].findViewById(R.id.engName);
            tv.setText(englishNames[position]);

            checkBoxArray[position]=(CheckBox)viewArray[position].findViewById(R.id.checkBox1);
        }

        checkBoxArray[position].setChecked(checked[position]);
        checkBoxArray[position].setOnCheckedChangeListener(this);
        return viewArray[position];
    }


    public void checkAll(boolean areChecked){
        for(int i=0; i<checked.length; i++){
            checked[i]=areChecked;
            if(checkBoxArray[i] != null)
                checkBoxArray[i].setChecked(areChecked);
        }
        notifyDataSetChanged();
    }

    public void onCheckedChanged(CompoundButton cb, boolean isChecked) {
        for(int i=0; i<checked.length; i++){
            if(cb == checkBoxArray[i])
                checked[i]=isChecked;
        }




    }
    public boolean itemIsChecked(int i){
        return checked[i];
    }

}

的布局是相当简单的，所以我将不会发布他们，除非有人认为他们是相关的。

The layouts are fairly simple so I won't post them unless anyone thinks they are relevant.

现在的问题是，一些复选框都没有响应。这似乎是那些第一次显示布局时是可见的。任何你需要向下滚动按预期工作。

The problem is that some of the CheckBoxes are not responding. It seems to be the ones that are visible when the layout is first displayed. Any that you have to scroll down to work as expected.

任何指针AP preciated。

Any pointers appreciated.

推荐答案

从答案的作品你的code，但效率不高（实际上你可以看到这一点，只需滚动的ListView 并检查的logcat 看到垃圾收集器做的工作）。一种改进 getView 将回收的观点方法是如下的：

Your code from the answer works but is inefficient(you can actually see this, just scroll the ListView and check the Logcat to see the garbage collector doing it's work). An improved getView method which will recycle views is the one below:

@Override
public View getView(int position, View convertView, ViewGroup parent) {
     LinearLayout view = (LinearLayout) convertView;
     if (view == null) {
          view = (LinearLayout) inflater.inflate(R.layout.record_view_start, parent, false);
     }
     TextView tv = (TextView) view.findViewById(R.id.engName);
     tv.setText(getItem(position));
     CheckBox cBox = (CheckBox) view.findViewById(R.id.checkBox1);
     cBox.setTag(Integer.valueOf(position)); // set the tag so we can identify the correct row in the listener
     cBox.setChecked(mChecked[position]); // set the status as we stored it        
     cBox.setOnCheckedChangeListener(mListener); // set the listener    
     return view;
}

OnCheckedChangeListener mListener = new OnCheckedChangeListener() {

     public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {   
         mChecked[(Integer)buttonView.getTag()] = isChecked; // get the tag so we know the row and store the status 
     }
};

关于您的问题，您的code，起初我还以为是因为你的方式设置的行错了，但我不明白为什么该适配器将这种行为作为您从列表中分离的行视图。另外，我甚至测试code和它的作品相当不错关于复选框（但内存处理很差）。也许你正在做，使适配器到不行别的东西？

Regarding your code from your question, at first I thought it was wrong because of the way you setup the rows but I don't see why the adapter will have that behavior as you detached the row view from the list. Also, I even tested the code and it works quite well regarding CheckBoxes(but with very poor memory handling). Maybe you're doing something else that makes the adapter to not work?

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