using Switch in ListView Controller

meirrotfleisch

Hi

I have a switch as part of the Customcontroller for my list view

I added delegate to it inside the controller but it runs the code on each item on load of the listview

my getView code is

public override View GetView(int position, View convertView, ViewGroup parent)
    {
        View view = convertView;



        if (myEvents[position]!=null)
        {

            if (view == null)
            {
                view = context.LayoutInflater.Inflate(Resource.Layout.EventListItem, null);
                view.FindViewById<TextView>(Resource.Id.eventTitle).Text = myEvents[position].EventName.ToString();
                view.FindViewById<Switch>(Resource.Id.switch4).Checked = myEvents[position].AlarmSet;
                if (myEvents[position].EventDescription != null)
                {
                    view.FindViewById<TextView>(Resource.Id.EventDescription).Text = myEvents[position].EventDescription.ToString();

                }
                view.FindViewById<TextView>(Resource.Id.eventStartDate).Text = myEvents[position].TimeLogged.ToString();
                view.FindViewById < TextView>(Resource.Id.eventId).Text = myEvents[position].id.ToString();
                if (MyUtils.IsOdd(position))
                {
                    view.SetBackgroundColor(Android.Graphics.Color.Azure);
                }
                else
                    {
                    view.SetBackgroundColor(Android.Graphics.Color.BurlyWood);
                }  
            }
        }

        Switch ASwitch = view.FindViewById<Switch>(Resource.Id.switch4);
        ASwitch.Click += delegate
         {
             MyUtils.ChangeAlarm(myEvents[position].id);
         };



        return view;
    }

What do i have wrong here??

Regards

M.R.

LandLu

GetView will be called over and over again when a view cell needs to be displayed on the screen so the Click event will be registered multiple times.
We need to put it in the:

if (view == null)
{
}

This will only be called at the initial time. Try to modify your code like:

public override View GetView(int position, View convertView, ViewGroup parent)
{
    View view = convertView;
    if (view == null)
    {
        view = LayoutInflater.From(context).Inflate(Resource.Layout.layout_item, parent, false);

        Switch switchBtn = view.FindViewById<Switch>(Resource.Id.switch4);
        switchBtn.Click += (sender, e) =>
        {
            var index = (int)((Switch)sender).Tag;
            Log.WriteLine(LogPriority.Debug, "test", index.ToString());
        };

    }

    Switch ASwitch = view.FindViewById<Switch>(Resource.Id.switch4);
    ASwitch.Checked = myEvents[position].AlarmSet;
    ASwitch.Tag = position;

    // ...

    return view;
}

Try to only put the initializing code in the block and if you want to assign the controls' property, it's better to use it like above.

LandLu

GetView will be called over and over again when a view cell needs to be displayed on the screen so the Click event will be registered multiple times.
We need to put it in the:

if (view == null)
{
}

This will only be called at the initial time. Try to modify your code like:

public override View GetView(int position, View convertView, ViewGroup parent)
{
    View view = convertView;
    if (view == null)
    {
        view = LayoutInflater.From(context).Inflate(Resource.Layout.layout_item, parent, false);

        Switch switchBtn = view.FindViewById<Switch>(Resource.Id.switch4);
        switchBtn.Click += (sender, e) =>
        {
            var index = (int)((Switch)sender).Tag;
            Log.WriteLine(LogPriority.Debug, "test", index.ToString());
        };

    }

    Switch ASwitch = view.FindViewById<Switch>(Resource.Id.switch4);
    ASwitch.Checked = myEvents[position].AlarmSet;
    ASwitch.Tag = position;

    // ...

    return view;
}

Try to only put the initializing code in the block and if you want to assign the controls' property, it's better to use it like above.

meirrotfleisch

@LandLu Thanks