Android 在ExpandableListView中自动滚动

我希望我的

ExpandableListView

在用户展开组时自动滚动，以便展开的组标题位于屏幕顶部。我已经尝试了

smoothScrollToPosition

，但这只是确保扩展组在屏幕上的某个位置可见。我想显式滚动它，使扩展组位于顶部，如本例所示：

Before expanding Group 3:                After expanding Group 3:

+=================+                      +=================+
| Group 1         |                      | Group 3         |
+-----------------+                      +-----------------+
| Group 2         |                      |   Grp 3 Child 1 |
+-----------------+                      +-----------------+
| Group 3         |                      |   Grp 3 Child 2 |
+-----------------+                      +-----------------+
| Group 4         |                      | Group 4         |
+=================+                      +=================+

这将滚动到所选项目，

---

单击组项时调用此属性。

从xml将此属性添加到ExpandibleListView标记中。这应该行得通。

将

android:transcriptMode=“disabled”

设置到我的

ExpandibleListView

也行得通。当参数设置为“正常”时，没有任何方法工作（

setSelectedGroup

，

setSelectionFromTop

等）

---

只有

setSmoothScroll

可以工作，但不喜欢它的效果。

下面的代码是一个适合我的解决方案

public boolean onGroupClick(ExpandableListView parent, View v,int groupPosition, long id) {
    // TODO Auto-generated method stub
    //mExpandableList.setSelectionFromTop(groupPosition, 0);

Boolean shouldExpand = (!mExpandableList.isGroupExpanded(groupPosition));        
    mExpandableList.collapseGroup(lastClickedPosition);

    if (shouldExpand){
        //generateExpandableList();
        mExpandableList.expandGroup(groupPosition);
        mExpandableList.setSelectionFromTop(groupPosition, 0);
    }                
    lastClickedPosition = groupPosition;
    return true;        
}

---

这对我有用。将其放入适配器：

public void onGroupExpanded(final int groupPosition) {
    super.onGroupExpanded(groupPosition);

    listView.setSelectedGroup(groupPosition);
}

---

下面的代码对我很有用。希望能有所帮助。使用下面的代码在onGroupExpand中实现OnGroupExpandListener

public void onGroupExpand(final int groupPosition) {
super.onGroupExpand(groupPosition);

expandableListView.post(new Runnable() {

    @Override
    public void run() {
        expandableListView.setSelection(groupPosition);
        if(expandableListView.getChildAt(groupPosition)!=null)
        expandableListView.requestChildRectangleOnScreen(expandableListView.getChildAt(groupPosition),
                new Rect(0, 0, expandableListView.getChildAt(groupPosition).getRight(), expandableListView.getChildAt(groupPosition).getHeight()), false);
    }
});

---

}这个对我有用

expandList.setOnGroupClickListener(new ExpandableListView.OnGroupClickListener() {
        @Override
        public boolean onGroupClick(ExpandableListView parent, View v, int groupPosition, long id) {

            if (!parent.isGroupExpanded(groupPosition)) {
                parent.expandGroup(groupPosition);
            } else {
                parent.collapseGroup(groupPosition);
            }
            parent.setSelectedGroup(groupPosition);

            return true;
        }
    });

作为滚动体的主要工作部件是

parent.setSelectedGroup(groupPosition);

---

setSelectedGroup

可以工作，但如果您想获得平滑的滚动效果，请使用

smoothScrollToPositionFromTop

，如下所示：

    expandableListView.setOnGroupClickListener(new ExpandableListView.OnGroupClickListener() {
        @Override
        public boolean onGroupClick(ExpandableListView parent, View v, int groupPosition, long id) {
            parent.smoothScrollToPositionFromTop(groupPosition,0);
            if (expandableListView.isGroupExpanded(groupPosition))
                expandableListView.collapseGroupWithAnimation(groupPosition);
            else expandableListView.expandGroupWithAnimation(groupPosition);
            return true;
        }
    });

---

使用平滑滚动动画可以实现同样的效果吗？如果您使用

parent.expandGroup（groupPosition，true）

则动画将自动进行，而您不必自己执行，这可能会帮助您实现平滑滚动（但您可能需要计算列表中每个项目的高度）。

    expandableListView.setOnGroupClickListener(new ExpandableListView.OnGroupClickListener() {
        @Override
        public boolean onGroupClick(ExpandableListView parent, View v, int groupPosition, long id) {
            parent.smoothScrollToPositionFromTop(groupPosition,0);
            if (expandableListView.isGroupExpanded(groupPosition))
                expandableListView.collapseGroupWithAnimation(groupPosition);
            else expandableListView.expandGroupWithAnimation(groupPosition);
            return true;
        }
    });