My binded properties dosent work on change

Question

Hey,

I have some properties who are binded in xaml code and when i change some values of those properties then it dosent sync over to the xaml code...
I guess that i miss something but cant find what...
Any suggestions?

Here is my XAML Code:
<StackLayout Orientation="Horizontal">
<ImageButton Source="Left_Arrow.png"
x:Name="PreviousButton"
HorizontalOptions="StartAndExpand"
Command="{Binding BackOneDayCommand}"
BackgroundColor="Transparent">
</ImageButton>
<Label x:Name="CurrentDayLbl"
FontSize="28"
HorizontalOptions="Center"
Text="{Binding CurrentDay}">
</Label>
<ImageButton Source="Right_Arrow.png"
Command="{Binding ForwardOneDayCommand}"
HorizontalOptions="EndAndExpand"
BackgroundColor="Transparent">
</ImageButton>
</StackLayout>

And here is my C# Code:
public string CurrentDay { get; set; }
public Command BackOneDayCommand { get; }
public Command ForwardOneDayCommand { get; }
public bool WorkoutsListVisible { get; set; }
public bool NoTrainingLblVisible { get; set; }

        public ObservableCollection<Workouts> WorkoutsListSource { get; set; }

        public TodaysWorkoutViewModel()
        {
            CurrentSelectedWeekDay = DateTime.Today;


            CurrentDay = CurrentSelectedWeekDay.DayOfWeek.ToString();

            BackOneDayCommand = new Command(PreviousButton_Clicked);
            ForwardOneDayCommand = new Command(NextButton_Clicked);
        }

        public void PreviousButton_Clicked()
        {
            CurrentSelectedWeekDay = CurrentSelectedWeekDay.AddDays(-1);
            CurrentDay = CurrentSelectedWeekDay.DayOfWeek.ToString();
        }
        public void NextButton_Clicked()
        {
            CurrentSelectedWeekDay = CurrentSelectedWeekDay.AddDays(+1);
            CurrentDay = CurrentSelectedWeekDay.DayOfWeek.ToString();
        }

Thankful for some help!

Answer 1

Hello @Carlo Goretti ,​

Welcome to our Microsoft Q&A platform!

In order to update the view at runtime, the model class should implement INotifyPropertyChanged interface to raise the PropertyChanged event when a property is changed. In your project, please make the 'CurrentDay' parameter to raise the PropertyChanged event in the model class.

Check the code:

   public class CustomModel : INotifyPropertyChanged  
   {  
       private string currentDay;  
       public string CurrentDay  
       {  
           get  
           {  
               return currentDay;  
           }  
           set  
           {  
               if (currentDay != value)  
               {  
                   currentDay = value;  
                   NotifyPropertyChanged();  
               }  
           }  
       }  
     
       ...  
     
       protected virtual void NotifyPropertyChanged([CallerMemberName] string propertyName = "")  
       {  
           PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));  
       }  
     
       public event PropertyChangedEventHandler PropertyChanged;  
   }  

Best Regards,

Jarvan Zhang

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Answer 2

It seems that you don't implement INotifyPropertyChangend