Ui is not updating on realtime

Question

I have a listview for displaying all the items that i getting from api.i have a live event which will modify one field inside the item of type observablecollection

i want to update the good count on real time. i debugged the code its getting updated in my list but only updating the UI on a user scroll. Here is my viewmodel

public class JobViewModel: INotifyPropertyChanged
    {
        private ObservableCollection items;

        public event PropertyChangedEventHandler PropertyChanged;


        public ObservableCollection Items
        {
            get { return items; }
            set
            {

                items = value;
                if (items != value)
                {
                    items = value;
                    OnPropertyChanged(nameof(Items));
                }
            }
        }
 protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
        {
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
        }
}
}
private void updateJoblistOnEvent(NotificationEntity message)
        {
            var jobId = message.JobId;
            Job job = Items.FirstOrDefault(a => a.JobId.Equals(jobId));

            switch (message.EventCode)
            {


                case MessageTypeEnum.Pulse: //Pulse
                job.GoodCount = job.GoodCount + 1;

                //job.Status = 'Running';
                break;
                default:
                    break;
            }
        }

i am suspecting two things

CachingStrategy="RecycleElement" i removed this one that its not updating with scroll also
any problem with INotifyPropertyChanged, i tried to remove one item from list its working and updating the ui.i want to update the field inside the item can any one help me

Gerald Versluis · Accepted Answer

As deduced from the comments, you need to also implement the INotifyPropertyChanged interface on the Job object. Using the ObservableCollection only helps for changes in that collection, so when you remove or add a Job object, not if something changes inside the Job object.

So, in your Job object do this (code reverse engineered from what you posted):

public class Job : INotifyPropertyChanged
{
   private int goodCount;
   public int GoodCount
   {
       get { return goodCount; }
       set
       {
           if (goodCount != value)
           {
               goodCount = value;
               OnPropertyChanged(nameof(GoodCount));
            }
        }
    }

    protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
    {
        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
    }
}

You could remove the INotifyPropertyChanged from your JobViewModel, but you probably need it there at some point as well

Ui is not updating on realtime

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