在特定场景中单击 ExpandableListView.onGroupClick 上的子项后检查视图

Posted 2023-04-19

【中文标题】在特定场景中单击 ExpandableListView.onGroupClick 上的子项后检查视图

【英文标题】：Checking a view after clicking child on ExpandableListView.onGroupClick in a specific scenario

【发布时间】：2020-12-27 19:39:23

【问题描述】：

我有一个包含 6 个项目的扩展列表，当第三个可以扩展到另一个 12 个列表时。

一切都很好，展开，折叠，打开片段......我的问题是我不能只在一个非常特殊的情况下设置选中的项目（更改其背景）：当我选择一个子项目时（从第 3 个开始）展开列表），不关闭展开列表，选择展开列表下方的一项（大于2）。

例如：我选择第 2 项，列表展开，然后我向下滚动并从第一个（组）列表中选择最后一项 - 它有效，但它是第 3 项的检查（更改 bg）而不是第 6 项！

我猜它有一些带有回收视图的东西，但我无法弄清楚。我用谷歌搜索了很多，但没有找到一个可行的例子。有可能吗？

请帮忙。天呐

mMenuAdapter = new ExpandableListAdapter (this, listDataHeader, listDataChild, expandableList);

expandableList.setAdapter (mMenuAdapter);



expandableList.setOnGroupClickListener (new ExpandableListView.OnGroupClickListener () 
            @Override
            public boolean onGroupClick (ExpandableListView expandableListView, View view, int i, long l) 

                if (currentView != null)
                    currentView.setBackgroundColor (getResources ().getColor (R.color.transparent));


                if (expandableListView.isGroupExpanded (2))
                    expandableListView.collapseGroup (2);


                if (i != 2) 
                    currentView = view;
                    currentView.setBackgroundColor (getResources ().getColor (R.color.veryLightBg));
                 else 
                    currentView = null;
                    return false;
                

                mainMenuClicked (i); // opens the right fragment

                return true;
            
        );


expandableList.setOnChildClickListener (new ExpandableListView.OnChildClickListener () 
            @Override
            public boolean onChildClick (ExpandableListView expandableListView, View view, int i, int i1, long l) 

                if (currentView != null)
                    currentView.setBackgroundColor (getResources ().getColor (R.color.transparent));

                currentView = view;
                currentView.setBackgroundColor (getResources ().getColor (R.color.veryLightBg));

                childMenuClicked (i1);
                return false;
            
        );

适配器：

public class ExpandableListAdapter extends BaseExpandableListAdapter 

    private Context mContext;
    private List<ExpandedMenuItem> mListDataHeader; 
    private HashMap<ExpandedMenuItem, List<String>> mListDataChild;
    ExpandableListView expandList;


    public ExpandableListAdapter(Context context, List<ExpandedMenuItem> listDataHeader, HashMap<ExpandedMenuItem, List<String>> listChildData, ExpandableListView mView) 
        this.mContext = context;
        this.mListDataHeader = listDataHeader;
        this.mListDataChild = listChildData;
        this.expandList = mView;
    


    @Override
    public int getGroupCount() 
        return this.mListDataHeader.size();
    


    public int getChildrenCount(int groupPosition) 
        int childCount = 0;
        if (groupPosition == 2)
            childCount = this.mListDataChild.get(this.mListDataHeader.get(groupPosition)).size();

        return childCount;
    


    @Override
    public Object getGroup(int groupPosition) 
        return this.mListDataHeader.get(groupPosition);
    


    @Override
    public Object getChild(int groupPosition, int childPosition) 
        return this.mListDataChild.get(this.mListDataHeader.get(groupPosition)).get(childPosition);
    


    @Override
    public long getGroupId(int groupPosition) 
        return groupPosition;
    


    @Override
    public long getChildId(int groupPosition, int childPosition) 
        return childPosition;
    


    @Override
    public boolean hasStableIds() 
        return false;
    


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

        ExpandedMenuItem headerTitle = (ExpandedMenuItem) getGroup(groupPosition);

        if (convertView == null) 
            LayoutInflater infalInflater = (LayoutInflater) this.mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            convertView = infalInflater.inflate(R.layout.main_list, null);
        

        TextView lblListHeader = convertView.findViewById(R.id.single_menu);

        if (groupPosition == 2) 
            if (!isExpanded)
                lblListHeader.setText (mContext.getString (R.string.products_category));
            else
                lblListHeader.setText (mContext.getString (R.string.expand_products_category));


         else 
            lblListHeader.setText (headerTitle.getName ());
        

        return convertView;
    



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

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

        if (convertView == null) 
            LayoutInflater infalInflater = (LayoutInflater) this.mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            convertView = infalInflater.inflate(R.layout.sub_list, null);
        

        TextView txtListChild = convertView.findViewById(R.id.single_menu);

        txtListChild.setText(childText);

        return convertView;
    


    @Override
    public boolean isChildSelectable(int groupPosition, int childPosition) 
        return true;
    

【参考方案1】：

经过多次搜索，我得出了完整的答案。

首先，我为列表视图添加了一个checkableRowLayout 类（正如answer 所建议的那样），因此可以对其进行检查：

public class checkableRowLayout extends ConstraintLayout implements Checkable 

    private boolean isChecked = false;


    public checkableRowLayout(@NonNull Context context, @Nullable AttributeSet attrs) 
        super(context, attrs);
    

    public boolean isChecked() 
        return isChecked;
    

    public void setChecked(boolean isChecked) 
        this.isChecked = isChecked;
        changeColor(isChecked);
    

    public void toggle() 
        this.isChecked = !this.isChecked;
        changeColor(this.isChecked);
    

    private void changeColor(boolean isChecked)
        if (isChecked) 
            setBackgroundColor(getResources().getColor(R.color.veryveryLightGrey));
         else 
            setBackgroundColor(getResources().getColor(android.R.color.transparent));
        
    

接下来，我在列表行的xml 源文件中设置这个类（而不是作为根视图的“LinearLayout”），如果主列表项的视图和子项：

<?xml version="1.0" encoding="utf-8"?>
<com.myapp.togo.checkableRowLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:orientation="vertical"
    android:layout_
    android:layout_>

    <TextView
        android:layout_
        android:layout_
        android:layout_marginStart="20sp"
        android:textColor="@color/blue"
        android:textSize="20sp"
        android:id="@+id/title"
        android:paddingBottom="15sp"
        android:paddingTop="15sp"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintBottom_toBottomOf="parent"/>

</com.myapp.togo.checkableRowLayout>

我在click listeners 中为组和子列表项添加了 2 行：

expandableList.setOnChildClickListener (new ExpandableListView.OnChildClickListener () 
            @Override
            public boolean onChildClick (ExpandableListView expandableListView, View view, int i, int i1, long l) 

                expandableList.setItemChecked(i+i1+1, true); // this is the new line
                expandableList.setSelection(i+i1+1); // this is the new line
                
                childMenuClicked (i1);

                return false;
            
        );

expandableList.setOnGroupClickListener (new ExpandableListView.OnGroupClickListener () 
            @Override
            public boolean onGroupClick (ExpandableListView expandableListView, View view, int i, long l) 

                if (expandableListView.isGroupExpanded (2))
                    expandableListView.collapseGroup (2);

                expandableList.setItemChecked(i, true); // this is the new line
                expandableList.setSelection(i); // this is the new line
                
                if (i == 2)
                    return false;
                
                mainMenuClicked (i);

                return true;
            
        );

现在可以了。我希望你觉得它有帮助！