Question

在ExpandableListView中，有没有办法隐藏没有孩子的群组指标？

Answer 1

试试这个＆gt;＆gt;＆gt;

所有项目

 getExpandableListView().setGroupIndicator(null);

在xml中

android:groupIndicator="@null"

Answer 2

android:groupIndicator属性采用启用状态的drawable。也就是说，您可以为不同的状态设置不同的图像。

当小组没有孩子时，相应的状态为'state_empty'

请参阅以下参考链接：

this和this

对于state_empty，你可以设置一个不混淆的不同图像，或者只是使用透明色来显示任何内容......

将此项目与其他人一起添加到有状态的drawable中....

<item android:state_empty="true" android:drawable="@android:color/transparent"/>

所以，你的州名单可以是这样的：

<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:state_empty="true" android:drawable="@android:color/transparent"/>
    <item android:state_expanded="true" android:drawable="@drawable/my_icon_max" />
    <item android:drawable="@drawable/my_icon_min" />
</selector>

如果您使用的是ExpandableListActivity，可以在onCreate中设置groupindicator，如下所示：

getExpandableListView().setGroupIndicator(getResources().getDrawable(R.drawable.my_group_statelist));

我已经对此进行了测试。

Answer 3

根据StrayPointer的回答和博客中的代码，您可以进一步简化代码：

在你的xml中添加下面的ExpandableListView：

android:groupIndicator="@android:color/transparent"

然后在适配器中执行以下操作：

@Override
protected void bindGroupView(View view, Context paramContext, Cursor cursor, boolean paramBoolean){
    **...**

    if ( getChildrenCount( groupPosition ) == 0 ) {
       indicator.setVisibility( View.INVISIBLE );
    } else {
       indicator.setVisibility( View.VISIBLE );
       indicator.setImageResource( isExpanded ? R.drawable.list_group_expanded : R.drawable.list_group_closed );
    }
}

通过使用setImageResource方法，您可以使用单行完成所有操作。您的适配器中不需要三个Integer数组。对于展开和折叠状态，您也不需要XML选择器。一切都是通过Java完成的。

另外，默认情况下，当某个群组展开时，此方法也会显示正确的指示符，而这与博客中的代码无关。

Answer 4

正如其他答案所述，由于Android将未展开的列表组视为空，即使该组有子项，也不会绘制图标。

此链接为我解决了问题： http://mylifewithandroid.blogspot.com/2011/06/hiding-group-indicator-for-empty-groups.html

基本上你必须将默认的drawable设置为透明，将drawable作为ImageView移动到组视图中并切换适配器中的图像。

Answer 5

在您的代码中，只需将自定义xml用于组列表，然后将 ImageView 用于 GroupIndicator 。

在 ExpandableListAdapter

中添加以下数组

private static final int[] EMPTY_STATE_SET = {};
private static final int[] GROUP_EXPANDED_STATE_SET = { android.R.attr.state_expanded };
private static final int[][] GROUP_STATE_SETS = { EMPTY_STATE_SET, // 0
GROUP_EXPANDED_STATE_SET // 1
};

也可以在 ExpandableListAdapter的方法中添加如下内容

public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) 
{ 
    if (convertView == null) 
    {
        LayoutInflater infalInflater = (LayoutInflater) this._context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        convertView = infalInflater.inflate(R.layout.row_group_list, null);
    }

    //Image view which you put in row_group_list.xml
    View ind = convertView.findViewById(R.id.iv_navigation);
    if (ind != null)
    {
        ImageView indicator = (ImageView) ind;
        if (getChildrenCount(groupPosition) == 0) 
        {
            indicator.setVisibility(View.INVISIBLE);
        } 
        else 
        {
            indicator.setVisibility(View.VISIBLE);
            int stateSetIndex = (isExpanded ? 1 : 0);
            Drawable drawable = indicator.getDrawable();
            drawable.setState(GROUP_STATE_SETS[stateSetIndex]);
        }
    }

    return convertView;
}

<强>参考： http://mylifewithandroid.blogspot.in/2011/06/hiding-group-indicator-for-empty-groups.html

Answer 6

这可能是另一种来自XML的方式，设置为android:groupIndicator="@null"

参考链接：https://stackoverflow.com/a/5853520/2624806

Answer 7

建议你我的解决方案：

1）清除默认的groupIndicator：

<ExpandableListView
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"       
    android:layout_width="wrap_content"
    android:layout_height="240dp"        
    android:layout_gravity="start"
    android:background="#cccc"  
    android:groupIndicator="@android:color/transparent"     
    android:choiceMode="singleChoice"
    android:divider="@android:color/transparent"        
    android:dividerHeight="0dp"  
     />

2）在ExpandableAdapter中：

@Override
public View getGroupView(int groupPosition, boolean isExpanded,
        View convertView, ViewGroup parent) {
    if (convertView == null) {
        convertView = new TextView(context);
    }
    ((TextView) convertView).setText(groupItem.get(groupPosition));     
    ((TextView) convertView).setHeight(groupHeight);
    ((TextView) convertView).setTextSize(groupTextSize);

    //create groupIndicator using TextView drawable
    if (getChildrenCount(groupPosition)>0) {
        Drawable zzz ;
        if (isExpanded) {
            zzz = context.getResources().getDrawable(R.drawable.arrowup);
        } else {
            zzz = context.getResources().getDrawable(R.drawable.arrowdown);
        }                               
        zzz.setBounds(0, 0, groupHeight, groupHeight);
        ((TextView) convertView).setCompoundDrawables(null, null,zzz, null);
    }       
    convertView.setTag(groupItem.get(groupPosition));       

    return convertView;
}

Answer 8

在XML

中

android:groupIndicator="@null"

在ExpandableListAdapter - ＆gt; getGroupView复制以下代码

if (this.mListDataChild.get(this.mListDataHeader.get(groupPosition)).size() > 0){
      if (isExpanded) {
          arrowicon.setImageResource(R.drawable.group_up);
      } else {
          arrowicon.setImageResource(R.drawable.group_down);
      }
}

Answer 9

使用它对我来说非常有用。

<selector xmlns:android="http://schemas.android.com/apk/res/android">

<item android:drawable="@drawable/group_indicator_expanded" android:state_empty="false" android:state_expanded="true"/>
<item android:drawable="@drawable/group_indicator" android:state_empty="true"/>
<item android:drawable="@drawable/group_indicator"/>

</selector>

Answer 10

简单地说，您为隐藏的组头创建了一个高度为0的新xml布局。例如，它是'group_list_item_empty.xml'

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"              
              android:layout_width="match_parent"
              android:layout_height="0dp">
</RelativeLayout>

然后您的正常组头布局为'your_group_list_item_file.xml'

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:layout_width="match_parent"
              android:layout_height="48dp"
              android:orientation="horizontal">
    ...your xml layout define...
</LinearLayout>

最后，您只需更新Adapter Class中的getGroupView方法：

public class MyExpandableListAdapter extends BaseExpandableListAdapter{   

    //Your code here ...

    @Override
    public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup viewGroup) {
        if (Your condition to hide the group header){
            if (convertView == null || convertView instanceof LinearLayout) {
                LayoutInflater mInflater = (LayoutInflater) context.getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
                convertView = mInflater.inflate(R.layout.group_list_item_empty, null);
            }           
            return convertView;
        }else{      
            if (convertView == null || convertView instanceof RelativeLayout) {
                LayoutInflater mInflater = (LayoutInflater) context.getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
                convertView = mInflater.inflate(R.layout.your_group_list_item_file, null);              
            }   
            //Your code here ...
            return convertView;
        }
    }
}

重要：布局文件的根标签（隐藏和正常）必须不同（如上例所示，LinearLayout和RelativeLayout）

Answer 11

您是否尝试更改+的属性ExpandableListView？

Answer 12

只想改进Mihir Trivedi的答案。您可以将它放在MyExpandableListAdapter类

中的getGroupView（）中

    View ind = convertView.findViewById(R.id.group_indicator);
    View ind2 = convertView.findViewById(R.id.group_indicator2);
    if (ind != null)
    {
        ImageView indicator = (ImageView) ind;
        if (getChildrenCount(groupPosition) == 0)
        {
            indicator.setVisibility(View.INVISIBLE);
        }
        else
        {
            indicator.setVisibility(View.VISIBLE);
            int stateSetIndex = (isExpanded ? 1 : 0);

            /*toggles down button to change upwards when list has expanded*/
            if(stateSetIndex == 1){
                ind.setVisibility(View.INVISIBLE);
                ind2.setVisibility(View.VISIBLE);
                Drawable drawable = indicator.getDrawable();
                drawable.setState(GROUP_STATE_SETS[stateSetIndex]);
            }
            else if(stateSetIndex == 0){
                ind.setVisibility(View.VISIBLE);
                ind2.setVisibility(View.INVISIBLE);
                Drawable drawable = indicator.getDrawable();
                drawable.setState(GROUP_STATE_SETS[stateSetIndex]);
            }
        }
    }

...至于布局视图，这就是我的group_items.xml似乎是

的方式

<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">

<TextView
    android:id="@+id/group_heading"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:paddingLeft="20dp"
    android:paddingTop="16dp"
    android:paddingBottom="16dp"
    android:textSize="15sp"
    android:textStyle="bold"/>

<ImageView
    android:id="@+id/group_indicator"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:src="@android:drawable/arrow_down_float"
    android:layout_alignParentRight="true"
    android:paddingRight="20dp"
    android:paddingTop="20dp"/>

<ImageView
    android:id="@+id/group_indicator2"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:src="@android:drawable/arrow_up_float"
    android:layout_alignParentRight="true"
    android:visibility="gone"
    android:paddingRight="20dp"
    android:paddingTop="20dp"/>

希望有所帮助......记得留下一个upvote

Answer 13

此处发布的答案将使您的小组指示器消失，即使小组有孩子也是如此。

要解决此问题，请覆盖组指示器。

首先，将您的组指示器设置为空：

    ExpandableListView.setGroupIndicator(null);

然后，转到包含标题的 xml，并添加带有可绘制对象的 ImageView。

之后，转到您的 ExpandableListAdapter.java，并在“getGroupView”部分中，执行以下操作：

public View getGroupView(int groupPosition, boolean isExpanded,
                         View convertView, ViewGroup parent) {
    String headerTitle = (String) getGroup(groupPosition);
    if (convertView == null) {
        LayoutInflater infalInflater = (LayoutInflater) this._context
                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        convertView = infalInflater.inflate(R.layout.list_group, null);
    }

    TextView lblListHeader = convertView
            .findViewById(R.id.lblListHeader); // this is your header

    ImageView groupIndicator = convertView.findViewById(R.id.group_indicator); // this is the ImageView included in your xml to override the indicator

    if (getChildrenCount(groupPosition) == 0) {
        convertView.setVisibility(View.GONE);
        lblListHeader.setVisibility(View.GONE);
        convertView.setPadding(0,0,0,0); //try not to include padding on your xml, and instead define the padding here.

    } else {
        convertView.setVisibility(View.VISIBLE);
        convertView.setPadding(8,8,8,0);
        lblListHeader.setVisibility(View.VISIBLE);
        lblListHeader.setTypeface(font);
        lblListHeader.setText(headerTitle);
        if (isExpanded) { //this is the part where we define our group indicator based on the expanded status of the adapter
            groupIndicator.setImageResource(R.drawable.group_indicator_expanded);
        } else {
            groupIndicator.setImageResource(R.drawable.group_indicator_empty);
        }
    }

    return convertView;
}

Answer 14

convertView.setVisibility（View.GONE）应该可以解决问题。

@Override
public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {
    DistanceHolder holder;
    if (convertView == null) {
        convertView = LayoutInflater.from(context).inflate(R.layout.list_search_distance_header, parent, false);
        if (getChildrenCount(groupPosition)==0) {
            convertView.setVisibility(View.GONE);
        }

ExpandableListView - 隐藏没有子项的组的指示符

14 个答案: