带有复选框的Android ExpandableListView，控制选中状态

Question

friend ，

我正在尝试编写一个在 ExpandableListView 中使用复选框的应用程序，我在这里遇到了一个问题，即维护应用程序的复选框状态，我从 here 得到了示例，我的问题是保持复选框的选中状态，每当我选中其中一个复选框并展开列表时，复选框在它们应该具有的位置没有选中状态。我尝试通过添加 ArrayList 来存储商店的位置并在 getChildView() 中重新加载该位置来进行维护，但仍然没有实现我想做的事情。这是我的代码

public class ElistCBox extends ExpandableListActivity {

    private static final String LOG_TAG = "ElistCBox";
    ArrayList<String > chkState = new ArrayList<String>();
    static final String colors[] = {"grey","blue","yellow","red"};
    static final String shades[][] ={ { "lightgrey","#D3D3D3","dimgray","#696969", "sgi >gray 92","#EAEAEA"},
        { "dodgerblue 2","#1C86EE","steelblue >2","#5CACEE","powderblue","#B0E0E6"},
        { "yellow 1","#FFFF00", "gold 1","#FFD700","darkgoldenrod 1"," #FFB90F" },
        {"indianred 1","#FF6A6A", "firebrick 1","#FF3030", "maroon","#800000" } };

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle icicle)
    {
        super.onCreate(icicle);
        setContentView(R.layout.main); 
        SimpleExpandableListAdapter expListAdapter = new SimpleExpandableListAdapter( 
            this,
            createGroupList(),
            R.layout.group_row, new String[] { "colorName" },
            new int[] { R.id.childname }, createChildList(),
            R.layout.child_row,
            new String[] { "shadeName", "rgb" },
            new int[] { R.id.childname, R.id.rgb }
        ) { 
            @Override public View getChildView(final int groupPosition, final int childPosition, boolean isLastChild, View convertView, ViewGroup parent)
            {
                final View v = super.getChildView(groupPosition, childPosition, isLastChild, convertView, parent);

                final CheckBox chkColor = (CheckBox)v.findViewById(R.id.check1);

                if(chkState.contains(groupPosition+","+childPosition)){
                    chkColor.setChecked(true);
                }else{
                    chkColor.setChecked(false);
                }
                chkColor.setOnClickListener(new OnClickListener() {
                    @Override
                    public void onClick(View v) {
                        Log.e("Checkbox Onclick Listener", Integer.toString(groupPosition) + " - " + Integer.toString(childPosition));
                    }
                });
                chkColor.setOnCheckedChangeListener(new OnCheckedChangeListener() {
                    @Override
                    public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
                        Log.e("Checkbox check change Listener", Integer.toString(groupPosition) + " - " + Integer.toString(childPosition));
                        if(chkColor.isChecked()){
                            chkState.add(groupPosition+","+childPosition);
                        } else {
                            chkState.remove(groupPosition+","+childPosition); 
                        }
                    }
                });
                return super.getChildView(groupPosition, childPosition, isLastChild, convertView, parent);
            }
        };
        setListAdapter( expListAdapter );
    }

    public void onContentChanged  () {
        super.onContentChanged();
        Log.e( LOG_TAG, "onContentChanged" );
    }

    public boolean onChildClick(
            ExpandableListView parent, 
            View v, 
            int groupPosition,
            int childPosition,
            long id) {
        Log.e( LOG_TAG, "onChildClick: "+childPosition );
        CheckBox cb = (CheckBox)v.findViewById( R.id.check1 );
        if( cb != null )
        cb.toggle();
        return false;
    }

    public void  onGroupExpand  (int groupPosition) {
        Log.e( LOG_TAG,"onGroupExpand: "+groupPosition );
    }

    private List createGroupList() {
        ArrayList result = new ArrayList();
        for( int i = 0 ; i < colors.length ; ++i ) {
            HashMap m = new HashMap();
            m.put( "colorName",colors[i] );
            result.add( m );
        }
        return (List)result; 
    }

    private List createChildList() {
        ArrayList result = new ArrayList();
        for( int i = 0 ; i < shades.length ; ++i ) {
            ArrayList secList = new ArrayList();
            for( int n = 0 ; n < shades[i].length; n += 2 ) {
                HashMap child = new HashMap();
                child.put( "shadeName", shades[i][n] );
                child.put( "rgb", shades[i][n+1] ); secList.add( child );
            }
            result.add( secList );
        } 
        return result;
    }
}

Answer 1

这是我对这个问题的回答，你需要为单个 child 保持检查状态，并在点击 child 时检查它。经过一些研究，这是由于 android 的 View 生命周期导致 View 刷新，从而无法保持状态。

public class MyExpandableListAdapter extends BaseExpandableListAdapter {
//Variables
// Sample data set.  children[i] contains the children (String[]) for groups[i].
private String[] groups = { "People Names", "Dog Names", "Cat Names", "Fish Names" }; //headers
private String[][] children = {
        { "Arnold", "Barry", "Chuck", "David" },
        { "Ace", "Bandit", "Cha-Cha", "Deuce" },
        { "Fluffy", "Snuggles" },
        { "Goldy", "Bubbles" }
};
private String[] group_vaues = {"PN", "DN", "CN", "FN"};
private String[][] children_values = {
        { "Ar", "Ba", "Ch", "Da" },
        { "Ace", "Ban", "Cha", "Deu" },
        { "Flu", "Snu" },
        { "Gol", "Bub" }
};
ArrayList<ArrayList<Integer>> check_states = new ArrayList<ArrayList<Integer>>();

private Context context;

//Constructors
public MyExpandableListAdapter() {

}

public MyExpandableListAdapter(Context c) {
    this.context = c;
}

//Set Methods
public void setGroupsAndValues(String[] g, String[] v) {
    this.groups = g;
    this.group_vaues = v;
}

public void setChildrenAndValues(String[][] c, String[][] v) {
    this.children = c;
    this.children_values = v;
    //initialize the states to all 0;
    for(int i = 0; i < c.length; i++) {
        ArrayList<Integer> tmp = new ArrayList<Integer>();
        for(int j = 0; j < c[i].length; j++) {
            tmp.add(0);
        }
        check_states.add(tmp);
    }
}

//Get Methods
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 View getChildView(int groupPosition, int childPosition, boolean isLastChild,
        View convertView, ViewGroup parent) {
    View grid;


   LayoutInflater inflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
   grid = inflater.inflate(R.layout.specialty_list_item, parent, false);

   final int grpPos = groupPosition;
   final int childPos = childPosition;

    TextView header = (TextView)grid.findViewById(R.id.title);
    header.setText(getChild(groupPosition, childPosition).toString());
    final View tick = grid.findViewById(R.id.image);
    if(check_states.get(grpPos).get(childPos) == 1)
        tick.setVisibility(View.VISIBLE);
    else
        tick.setVisibility(View.GONE);

    grid.setOnClickListener(new OnClickListener(){
        @Override
        public void onClick(View v) {
            check_states.get(grpPos).set(childPos, 1);
            tick.setVisibility(View.VISIBLE);
        }
    });

    return grid;
}

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) {
    View grid;

    if(convertView==null){
       grid = new View(context);
       LayoutInflater inflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
       grid = inflater.inflate(R.layout.specialty_header, parent, false);
    }else{
       grid = (View)convertView;
    }

    TextView header = (TextView)grid.findViewById(R.id.specialty_header);
    header.setText(getGroup(groupPosition).toString());


    return grid;
}

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

public boolean hasStableIds() {
    return true;
}