3级ExpandableListView Android [英] 3 level ExpandableListView Android
问题描述
关于SO，我遇到了几个问题，并进行了尝试.
I have come across a few questions on SO regarding the same and have tried them.
在展开式列表中最多可以显示2个级别，但是单击第二个级别时不能显示第三个级别.
I can show upto 2 levels in the expandable list, but I cannot show the third level when I click the second level.
我已经尝试过类似的方法:-
I have tried something like so :-
ParentView(第一级)
ParentView (First Level)
public class ParentView : BaseExpandableListAdapter
{
public static int FIRST_LEVEL_COUNT = 6;
public static int SECOND_LEVEL_COUNT = 4;
public static int THIRD_LEVEL_COUNT = 10;
private Context context;
public ParentView(Context context)
{
this.context = context;
}
public ParentView()
{
}
public override Java.Lang.Object GetChild(int groupPosition, int childPosition)
{
return childPosition;
}
public override long GetChildId(int groupPosition, int childPosition)
{
return childPosition;
}
public override View GetChildView(int groupPosition, int childPosition, bool isLastChild, View convertView, ViewGroup parent)
{
var SecondLevelexplv = new CustExpListview(Application.Context);
SecondLevelexplv.SetAdapter(new SecondLevelAdapter(context));
SecondLevelexplv.SetGroupIndicator(null);
return SecondLevelexplv;
}
public override int GetChildrenCount(int groupPosition)
{
return 3;
}
public override Java.Lang.Object GetGroup(int groupPosition)
{
return groupPosition;
}
public override int GroupCount
{
get
{
return 5;
}
}
public override long GetGroupId(int groupPosition)
{
return groupPosition;
}
public override View GetGroupView(int groupPosition, bool isExpanded, View convertView, ViewGroup parent)
{
var tv = new TextView(Application.Context)
{
Text = "->FirstLevel",
};
tv.SetBackgroundColor(Color.Blue);
tv.SetPadding(10, 7, 7, 7);
return tv;
}
public override bool IsChildSelectable(int groupPosition, int childPosition)
{
return true;
}
public override bool HasStableIds
{
get
{
return true;
}
}
}
CustExpListView
CustExpListView
public class CustExpListview : ExpandableListView
{
public CustExpListview(Context context) : base(context)
{
}
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec)
{
widthMeasureSpec = MeasureSpec.MakeMeasureSpec(999999, MeasureSpecMode.AtMost);
heightMeasureSpec = MeasureSpec.MakeMeasureSpec(999999, MeasureSpecMode.AtMost);
OnMeasure(widthMeasureSpec, heightMeasureSpec);
}
}
SecondLevelAdapter
SecondLevelAdapter
public class SecondLevelAdapter : BaseExpandableListAdapter
{
public static int THIRD_LEVEL_COUNT = 10;
private Context context;
private readonly ParentView parentView;
public SecondLevelAdapter(Context context)
{
this.context = context;
}
public SecondLevelAdapter(ParentView parentView)
{
this.parentView = parentView;
}
public override Java.Lang.Object GetGroup(int groupPosition)
{
return groupPosition;
}
public override int GroupCount
{
get
{
return 5;
}
}
public override long GetGroupId(int groupPosition)
{
return groupPosition;
}
public override View GetGroupView(int groupPosition, bool isExpanded, View convertView, ViewGroup parent)
{
var tv = new TextView(Application.Context)
{
Text = "-->Second"
};
tv.SetPadding(12, 7, 7, 7);
tv.SetBackgroundColor(Color.GreenYellow);
return tv;
}
public override Java.Lang.Object GetChild(int groupPosition, int childPosition)
{
return childPosition;
}
public override long GetChildId(int groupPosition, int childPosition)
{
return childPosition;
}
public override View GetChildView(int groupPosition, int childPosition, bool isLastChild, View convertView, ViewGroup parent)
{
var tv = new TextView(Application.Context)
{
Text = "third"
};
tv.SetPadding(18, 5, 5, 5);
tv.SetBackgroundColor(Color.Green);
return tv;
}
public override int GetChildrenCount(int ChildPosition)
{
return 4;
}
public override bool IsChildSelectable(int groupPosition, int childPosition)
{
return true;
}
public override bool HasStableIds
{
get
{
return true;
}
}
}
我注意到的是，尽管GetGroup()被调用，但从不调用SecondLevelAdapter中的GetChildView().我实际上想将列表扩展到4个级别，但我本身仍然停留在3个级别.
What I noticed is that the GetChildView() in the SecondLevelAdapter is never called though the GetGroup() is called. I actually want to expand the list upto 4 levels, but I am stuck at the 3rd level itself.
感谢您的帮助.
推荐答案
问题在于-->Second的每一行都是一个完整的ExpandableListView，其中包含5个组.并且由于当前父组的高度不会针对子ExpandableListView自动扩展.您看不到打开的子级列表:third.
The problem is for every row of -->Second it is a whole ExpandableListView,which contains 5 Groups. And as the height of the current parent group won't expand automatically for the child ExpandableListView. You can't see the opened children list: third.
要解决此问题，需要进行一些更改:
To Fix the problem, there are a few changes to be made:
-
将
SecondLevelAdapter的GroupCount从5更改为1:
public override int GroupCount
{
get
{
//return 5;
return 1;//Change GroupCount to 1
}
}
您需要手动更改第二级ExpandableListView的高度.这可以通过实现GroupExpand和GroupCollapse事件来完成:
You need to change the height of every second level ExpandableListView manually. This can be done by implementing GroupExpand and GroupCollapse events:
ParentView.cs:
ParentView.cs:
public override View GetChildView(int groupPosition, int childPosition, bool isLastChild, View convertView, ViewGroup parent)
{
var SecondLevelexplv = new CustExpListview(Application.Context);
SecondLevelexplv.SetAdapter(new SecondLevelAdapter(context));
SecondLevelexplv.SetGroupIndicator(null);
SecondLevelexplv.GroupExpand += SecondLevelexplv_GroupExpand;
SecondLevelexplv.GroupCollapse += SecondLevelexplv_GroupCollapse;
return SecondLevelexplv;
}
private void SecondLevelexplv_GroupCollapse(object sender, ExpandableListView.GroupCollapseEventArgs e)
{
AbsListView.LayoutParams lp = new AbsListView.LayoutParams(AbsListView.LayoutParams.MatchParent, 70);
(sender as CustExpListview).LayoutParameters = lp;
}
private void SecondLevelexplv_GroupExpand(object sender, ExpandableListView.GroupExpandEventArgs e)
{
//expand the group and the height is the `children count` * `unit height`
AbsListView.LayoutParams lp = new AbsListView.LayoutParams(AbsListView.LayoutParams.MatchParent, 70 * 5);
(sender as CustExpListview).LayoutParameters = lp;
}
因此，它将正常工作:
这篇关于3级ExpandableListView Android的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
