Question

我正在摆弄我的自定义BaseExpandableListAdapter，在我的getChildView方法中，我似乎得到了子视图的随机位置。无论回收如何，我都会得到随机的排名顺序。例如，在convertView = null条件分支中，我得到：

LogCat打印在（ConvertView == null）：

childPosition：childPosition - 0 childPosition：childPosition - 1 childPosition：childPosition - 0 childPosition：childPosition - 3 childPosition：childPosition - 4 childPosition：childPosition - 0

LogCat打印在（ConvertView！= null）：

childPosition：childPosition - 1 childPosition：childPosition - 2 childPosition：childPosition - 3 childPosition：childPosition - 4 childPosition：childPosition - 5 childPosition：childPosition - 6 childPosition：childPosition - 7 childPosition：childPosition - 8 childPosition：childPosition - 0 childPosition：childPosition - 1 childPosition：childPosition - 0 childPosition：childPosition - 1

以下是我的适配器的代码：

public class MyExapndableListAdapter extends BaseExpandableListAdapter {

    private Context context;
    private List<String> headerList;
    private HashMap<String, List<String>> _listDataChild;

    public MyExapndableListAdapter(Context context, List<String> listDataHeader, HashMap<String, List<String>> listChildData) {
        this.context = context;
        this._listDataChild = listChildData;
        this.headerList = listDataHeader;

        Log.d("LIST CHILD", "" + _listDataChild.size());
        Log.d("LIST HEADER", "" + this.headerList.size());
    }


    @Override
    public int getGroupCount() {
        return this.headerList.size();
    }

    @Override
    public int getChildrenCount(int i) {
        return this._listDataChild.get(this.headerList.get(i)).size();
    }

    @Override
    public Object getGroup(int i) {
        return this.headerList.get(i);
    }

    @Override
    public Object getChild(int groupPosition, int childPosititon) {
        return this._listDataChild.get(this.headerList.get(groupPosition)).get(childPosititon);
    }

    @Override
    public long getGroupId(int i) {
        return i;
    }

    @Override
    public long getChildId(int i, int childPosition) {
        return childPosition;
    }

    @Override
    public boolean hasStableIds() {
        return false;
    }

    @Override
    public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {

        View v = convertView;

        String headerTitle = (String) getGroup(groupPosition);

        if (v == null) {
            LayoutInflater inflater = (LayoutInflater) this.context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            v = inflater.inflate(R.layout.list_group, null);
            ViewHolder holder = new ViewHolder();
            holder.addView(v.findViewById(R.id.blaGroup));
            v.setTag(holder);
        }

        ViewHolder holder = (ViewHolder) v.getTag();

        MyText title = (MyText) holder.getView(R.id.blaGroup);
        title.setText(headerTitle);

        return v;
    }

    @Override
    public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent) {


        final String childText = (String) getChild(groupPosition, childPosition);



        View row = convertView;

        if (row == null) {

//            Log.d("NULL VIEW", "childText - " +childText);
            Log.d("childPosition", "childPosition - " +childPosition);

            LayoutInflater inflater = (LayoutInflater) this.context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            row = inflater.inflate(R.layout.list_child, null);
            ViewGroup.LayoutParams lp = new ActionBar.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT);

            final float GESTURE_THRESHOLD_DIP = 30.0f;

            // Convert the dips to pixels
            final float scale = context.getResources().getDisplayMetrics().density;
            int pixel = (int) (GESTURE_THRESHOLD_DIP * scale + 0.5f);

            Typeface font = Typeface.createFromAsset(context.getAssets(), "fonts/pacifico.ttf");
            int fontColor = context.getResources().getColor(R.color.testColor);
            int strokeWidth = 5;
            int strokeColor = context.getResources().getColor(R.color.card_white);

            // Add TextView on the fly
            MyText text = new MyText(context, pixel, childText, font, fontColor, strokeWidth, strokeColor);
            text.setLayoutParams(lp);
            text.setText(childText);
            text.setTextSize(GESTURE_THRESHOLD_DIP);
            text.setId(3005);

            ((ViewGroup) row).addView(text);


            ViewHolder holder = new ViewHolder();
            holder.addView(text);
            row.setTag(holder);



        }

        else {
//            Log.d("NOT NULL VIEW", "childText - " +childText);
            Log.d("NOT NULL VIEW childPosition", "childPosition - " +childPosition);
        }

        ViewHolder holder = (ViewHolder) row.getTag();
        MyText text = (MyText) holder.getView(3005);
        text.setText(childText);

        return row;
    }

    public static class ViewHolder {

        private HashMap<Integer, View> storedViews = new HashMap<Integer, View>();

        public ViewHolder() {
        }

        public ViewHolder addView(View view) {
            int id = view.getId();
            storedViews.put(id, view);
            return this;
        }

        public View getView(int id) {
            return storedViews.get(id);
        }
    }

    @Override
    public boolean isChildSelectable(int i, int i2) {
        return true;
    }

}

Answer 1

您获得了一个随机位置，因为您使用的是 Hashmap 。 Hashmap有自己的方法来对其中的数据进行排序。所以我建议使用自定义对象而不是Hashmap。

Answer 2

那么childView的位置不是随机的，只是它们是来自不同组的子位置，与groupId一起打印它们你会明白发生了什么。此外，childPosition并不依赖于convertview是否为null，通常会为列表项调用getChildView，该列表项将在滚动时进入屏幕。希望这会有所帮助，如果你想要一个例子，请回复。

BaseExpandableListAdapter - getChildView随机位置

2 个答案: