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私はExpandbleListViewを持っているが（http://www.appliedcodelog.com/2016/06/expandablelistview-in-xamarin-android.html &ペーストここからコピー）。XamarinアンドロイドExpandbleListView追加子項目
これまでのところ、私は（リストlstCS;）私のリストを宣言し、ボタンのクリックハンドラで私の項目を追加し、（NotifyDataSetChangedを呼び出して、私のクラスではなくメソッドで子アイテムのために）
それだけで感じていませんでしたそれは魅力のように働くにもかかわらず、そうしている。いくつかのティップスはありますか？あなたが提供されるリンクでのアダプタを使用した場合は
using System;
using Android.Widget;
using System.Collections.Generic;
using Android.App;
using Android.Views;
using Android.Content;
using Android.OS;
using Android.Runtime;
namespace TestApp
{
public class ExpandableListAdapter : BaseExpandableListAdapter
{
private Activity _context;
private List<string> _listDataHeader;
private Dictionary<string, List<string>> _listDataChild;
public ExpandableListAdapter(Activity context, List<string> listDataHeader, Dictionary<String, List<string>> listChildData)
{
_context = context;
_listDataHeader = listDataHeader;
_listDataChild = listChildData;
}
//for cchild item view
public override Java.Lang.Object GetChild(int groupPosition, int childPosition)
{
return _listDataChild[_listDataHeader[groupPosition]][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)
{
string childText = (string)GetChild(groupPosition, childPosition);
if (convertView == null)
{
convertView = _context.LayoutInflater.Inflate(Resource.Layout.ListItemCustomLayout, null);
}
TextView txtListChild = (TextView)convertView.FindViewById(Resource.Id.lblListItem);
txtListChild.Text = childText;
return convertView;
}
public override int GetChildrenCount(int groupPosition)
{
return _listDataChild[_listDataHeader[groupPosition]].Count;
}
//For header view
public override Java.Lang.Object GetGroup(int groupPosition)
{
return _listDataHeader[groupPosition];
}
public override int GroupCount
{
get
{
return _listDataHeader.Count;
}
}
public override long GetGroupId(int groupPosition)
{
return groupPosition;
}
public override View GetGroupView(int groupPosition, bool isExpanded, View convertView, ViewGroup parent)
{
string headerTitle = (string)GetGroup(groupPosition);
convertView = convertView ?? _context.LayoutInflater.Inflate(Resource.Layout.HeaderCustomLayout, null);
var lblListHeader = (TextView)convertView.FindViewById(Resource.Id.lblListHeader);
lblListHeader.Text = headerTitle;
return convertView;
}
public override bool HasStableIds
{
get
{
return false;
}
}
public override bool IsChildSelectable(int groupPosition, int childPosition)
{
return true;
}
class ViewHolderItem : Java.Lang.Object
{
}
}
}
using Android.App;
using Android.Widget;
using Android.OS;
using System.Collections.Generic;
using System;
using System.Runtime.Remoting.Contexts;
namespace TestApp
{
[Activity(Label = "TestApp", MainLauncher = true)]
public class MainActivity : Activity
{
ExpandableListAdapter listAdapter;
ExpandableListView expListView;
List<string> listDataHeader;
Dictionary<string, List<string>> listDataChild;
int previousGroup = -1;
List<string> lstCS;
protected override void OnCreate(Bundle savedInstanceState)
{
base.OnCreate(savedInstanceState);
SetContentView(Resource.Layout.Main);
expListView = FindViewById<ExpandableListView>(Resource.Id.lvExp);
// Prepare list data
FnGetListData();
//Bind list
listAdapter = new ExpandableListAdapter(this, listDataHeader, listDataChild);
expListView.SetAdapter(listAdapter);
FnClickEvents();
Button button1 = (Button)FindViewById(Resource.Id.button1);
button1.Click += ButtonClicked;
}
void ButtonClicked(object sender, EventArgs args)
{
lstCS.Add("foo");
listAdapter.NotifyDataSetChanged();
Toast.MakeText(ApplicationContext, "df", ToastLength.Long).Show();
}
void FnClickEvents()
{
//Listening to child item selection
expListView.ChildClick += delegate (object sender, ExpandableListView.ChildClickEventArgs e) {
Toast.MakeText(this, "child clicked", ToastLength.Short).Show();
};
//Listening to group expand
//modified so that on selection of one group other opened group has been closed
expListView.GroupExpand += delegate (object sender, ExpandableListView.GroupExpandEventArgs e) {
if (e.GroupPosition != previousGroup)
expListView.CollapseGroup(previousGroup);
previousGroup = e.GroupPosition;
};
//Listening to group collapse
expListView.GroupCollapse += delegate (object sender, ExpandableListView.GroupCollapseEventArgs e) {
Toast.MakeText(this, "group collapsed", ToastLength.Short).Show();
};
}
void FnGetListData()
{
listDataHeader = new List<string>();
listDataChild = new Dictionary<string, List<string>>();
// Adding child data
listDataHeader.Add("Computer science");
listDataHeader.Add("Electrocs & comm.");
listDataHeader.Add("Mechanical");
// Adding child data
lstCS = new List<string>();
lstCS.Add("Data structure");
lstCS.Add("C# Programming");
lstCS.Add("Java programming");
lstCS.Add("ADA");
lstCS.Add("Operation reserach");
lstCS.Add("OOPS with C");
lstCS.Add("C++ Programming");
var lstEC = new List<string>();
lstEC.Add("Field Theory");
lstEC.Add("Logic Design");
lstEC.Add("Analog electronics");
lstEC.Add("Network analysis");
lstEC.Add("Micro controller");
lstEC.Add("Signals and system");
var lstMech = new List<string>();
lstMech.Add("Instrumentation technology");
lstMech.Add("Dynamics of machinnes");
lstMech.Add("Energy engineering");
lstMech.Add("Design of machine");
lstMech.Add("Turbo machine");
lstMech.Add("Energy conversion");
// Header, Child data
listDataChild.Add(listDataHeader[0], lstCS);
listDataChild.Add(listDataHeader[1], lstEC);
listDataChild.Add(listDataHeader[2], lstMech);
}
}
}
