I'm having a trouble with both ListView and RecyclerView
Initially, I created a ListView, everything is fine. Then I set onClick event for it so that every time I click an item, it changes its color to yellow. The OnClick function I wrote in the MainActivity. Problem is that when I test, not only that item changes its color but 2 items change. I read that it's because I reuse the view.
So I switch my tactics, using RecyclerView instead but same problem occurs. When I click one item to change its color, another below also changes. I guess it's because both ListView and RecyclerView reuse those Item so they confuse when I click one.
I don't know how to solve this problem, I found a solution is to add an array of boolean which marks which item is clicked but it doesn't work. Any idea guys?
So here is the code MainActivity
class MainActivity : Activity
{
public RecyclerView recyclerView;
public RecyclerView.LayoutManager manager;
public RecyclerView.Adapter adapter;
List<Row> lst;
protected override void OnCreate(Bundle bundle)
{
base.OnCreate(bundle);
// Set our view from the "main" layout resource
SetContentView(Resource.Layout.Main);
init();
recyclerView = (RecyclerView)FindViewById(Resource.Id.recyclerView);
manager = new LinearLayoutManager(this);
recyclerView.SetLayoutManager(manager);
CustomAdapter adapter = new CustomAdapter(lst, this);
adapter.ItemClick += onItemClick;
recyclerView.SetAdapter(adapter);
}
public void init()
{
lst = new List<Row>();
for (int i = 0; i < 15; i++)
{
Row row = new Row() { field1="1:43:00", field2="09-Apr-16", field3="KPI/Overflow", field4="Kevin Bacon", field5="Unowned", field6= "People Counting @ IPCAM-ID-C-1-1" };
lst.Add(row);
}
}
public void onItemClick(object sender, int position)
{
int itemPos = position + 1;
//Toast.MakeText(this, "this is " + itemPos, ToastLength.Short).Show();
recyclerView.GetChildAt(position).SetBackgroundColor(Android.Graphics.Color.Green);
}
}
Custom adapter
public class CustomAdapter : RecyclerView.Adapter
{
public Activity _activity;
public List<Row> lst;
public event EventHandler<int> ItemClick;
public CustomAdapter(List<Row> lst, Activity activity)
{
this.lst = lst;
this._activity = activity;
}
public override int ItemCount
{
get
{
return lst.Count;
}
}
public void OnClick(int position)
{
if (ItemClick!=null)
{
ItemClick(this, position);
}
}
public override void OnBindViewHolder(RecyclerView.ViewHolder holder, int position)
{
MyViewHolder myholder = holder as MyViewHolder;
myholder.textView1.Text = lst[position].field1;
myholder.textView2.Text = lst[position].field2;
myholder.textView3.Text = lst[position].field3;
myholder.textView4.Text = lst[position].field4;
myholder.textView5.Text = lst[position].field5;
myholder.textView6.Text = lst[position].field6;
}
public override RecyclerView.ViewHolder OnCreateViewHolder(ViewGroup parent, int viewType)
{
View v = this._activity.LayoutInflater.Inflate(Resource.Layout.item, parent, false);
TextView tv1 = (TextView)v.FindViewById(Resource.Id.textView1);
TextView tv2 = (TextView)v.FindViewById(Resource.Id.textView2);
TextView tv3 = (TextView)v.FindViewById(Resource.Id.textView3);
TextView tv4 = (TextView)v.FindViewById(Resource.Id.textView4);
TextView tv5 = (TextView)v.FindViewById(Resource.Id.textView5);
TextView tv6 = (TextView)v.FindViewById(Resource.Id.textView6);
MyViewHolder holder = new MyViewHolder(v, OnClick) { textView1 = tv1, textView2 = tv2, textView3 = tv3, textView4 = tv4, textView5 = tv5, textView6 = tv6 };
return holder;
}
}
class MyViewHolder : RecyclerView.ViewHolder
{
public TextView textView1, textView2, textView3, textView4, textView5, textView6;
public View mainView;
public MyViewHolder(View view, Action<int> listener) : base(view)
{
mainView = view;
mainView.Click += (sender, e) => listener(base.Position);
}
}
I followed the example for the OnClick handler on Xamarin site
https://developer.xamarin.com/guides/android/user_interface/recyclerview/
