Question

我使用“扩展式ListView”, 儿童行各有一个文本视图, 并在其中复选框。

我想做的是,当用户按下按钮时, 活动将决定哪些项目被检查, 并对这些项目做一些事情。

I read many posts on how ExpandableListView and checkboxes currently don t work well, and how I need to keep an additional data structure to keep track of what s has been selected, and not. This post covers that issue: ExpandableListView and checkboxes

完成! 我现在可以追踪所选的和未选的。

现在我想解决没有显示其状态的复选框问题。我注意到复选框在下列时间随机变化:

screen rotation changes
a group collapses/opens

我知道,有可能发现这些事件。

我想知道是否有办法手工设置复选框。

ExpandableListView elv = getExpandableListView();
for(int i = 0; i < elv.getChildCount(); i++) {
  CheckBox checkbox = ... somehow get checbox within the list
  checkbox.setChecked(checkList.at(i, j));
}

其中i 和 j 表示哪个组, 和子女, 和校对列表记录检查/ 校验的物品。

然而,我注意到,获得ChildCount () 的价值取决于有多少团体是开放的,而不一定告诉我我可以操纵哪个项目清单。

已经使用了可扩展的ListView, 并且一定有人有办法绕过这个问题。是否有明智的解决方案? 具体地说, 我正寻找方法检查/ 检查“ 集团扩大” 和“ 组合变化( 或类似事件) ” 列表中的适当项目。

提前感谢您!

Answer 1

检查以下样本中的可扩展列表适配器

/**
     * A simple adapter which maintains an ArrayList of photo resource Ids. 
     * Each photo is displayed as an image. This adapter supports clearing the
     * list of photos and adding a new photo.
     *
     */
    public class MyExpandableListAdapter extends BaseExpandableListAdapter {


        // Sample data set.  children[i] contains the children (String[]) for groups[i].
        private String[] groups = { "People Names", "Dog Names", "Cat Names", "Fish Names" };
        private String[][] children = {
                { "Arnold", "Barry", "Chuck", "David" },
                { "Ace", "Bandit", "Cha-Cha", "Deuce" },
                { "Fluffy", "Snuggles" },
                { "Goldy", "Bubbles" }
        };

        private ArrayList<ArrayList<Boolean>> checkboxStatus = new ArrayList<ArrayList<Boolean>>();

        public MyExpandableListAdapter() {
            int groupCount = groups.length;
            for(int i=0; i<groupCount; i++) 
            {
                int childCount = children[i].length;
                ArrayList<Boolean> childStatus = new ArrayList<Boolean>();
                for(int j=0; j<childCount; j++) {
                    childStatus.add(false);
                }
                checkboxStatus.add(childStatus);
            }
        }

        public Object getChild(int groupPosition, int childPosition) {
            return children[groupPosition][childPosition];
        }

        public long getChildId(int groupPosition, int childPosition) {
            return childPosition;
        }

        public int getChildrenCount(int groupPosition) {
            return children[groupPosition].length;
        }

        public TextView getGenericView() {

            // Layout parameters for the ExpandableListView
            AbsListView.LayoutParams lp = new AbsListView.LayoutParams(
                    ViewGroup.LayoutParams.MATCH_PARENT, 64);

            TextView textView = new TextView(ExpandableListCheckboxActivity.this);
            textView.setLayoutParams(lp);
            // Center the text vertically
            textView.setGravity(Gravity.CENTER_VERTICAL | Gravity.LEFT);
            // Set the text starting position
            textView.setPadding(36, 0, 0, 0);
            return textView;
        }

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

            CheckBox chkbox = new CheckBox(ExpandableListCheckboxActivity.this);
            chkbox.setTag("" + groupPosition + "," + childPosition);
            chkbox.setOnCheckedChangeListener(checkboxListener);
            chkbox.setText(children[groupPosition][childPosition]);

            chkbox.setChecked(checkboxStatus.get(groupPosition).get(childPosition));

            return chkbox;
        }

        public Object getGroup(int groupPosition) {
            return groups[groupPosition];
        }

        public int getGroupCount() {
            return groups.length;
        }

        public long getGroupId(int groupPosition) {
            return groupPosition;
        }

        public View getGroupView(int groupPosition, boolean isExpanded, View convertView,
                ViewGroup parent) {
            TextView textView = getGenericView();
            textView.setText(getGroup(groupPosition).toString());

            return textView;
        }

        public boolean isChildSelectable(int groupPosition, int childPosition) {
            return true;
        }

        public boolean hasStableIds() {
            return true;
        }

        private OnCheckedChangeListener checkboxListener = new OnCheckedChangeListener() {

            @Override
            public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
                String positions = buttonView.getTag().toString();
                int groupPosition = Integer.valueOf(positions.split(",")[0]);
                int childPosition = Integer.valueOf(positions.split(",")[1]);
                checkboxStatus.get(groupPosition).set(childPosition, isChecked);
            }
        };

    }

Answer 2

如果您只想在单击行时更改它:

elv.setOnChildClickListener(new ExpandableListView.OnChildClickListener() {
    @Override
    public boolean onChildClick(ExpandableListView parent, View v,
            int groupPosition, int childPosition, long id) {
        CheckBox checkbox = (CheckBox) v.findViewById(r.id.yourcheckbox)
        checkbox.setChecked(checkList.at(groupPosition, childPosition));    
        return true;
    }
});

友情链接