Binding IsVisible to a bool property in Xamarin Forms - xamarin.forms

Question

I've got a label that I want to bind to a boolean property (HasNotifications). However, when the property is false, the label stays visible. If I set the IsVisible property to false in the XAML, the label isn't visible so the issue appears to be with the binding.
XAML:
<AbsoluteLayout
HorizontalOptions="FillAndExpand"
VerticalOptions="FillAndExpand">
<Grid
HorizontalOptions="FillAndExpand"
VerticalOptions="FillAndExpand"
AbsoluteLayout.LayoutFlags="All"
AbsoluteLayout.LayoutBounds="0,0,1,1">
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
<RowDefinition Height="*" />
<RowDefinition Height="Auto" />
<RowDefinition Height="*" />
</Grid.RowDefinitions>
<Label
Text="Title"
HorizontalOptions="Center"
VerticalOptions="Center"
TextColor="White"
FontSize="Large"
FontAttributes="Bold"
Margin="5"
BindingContext="{x:Reference DashboardPageView}"
Grid.Row="0" />
<Label
Text="Notifications"
HorizontalOptions="Start"
VerticalOptions="Center"
TextColor="White"
FontSize="Medium"
FontAttributes="Bold"
Margin="3"
BindingContext="{x:Reference DashboardPageView}"
IsVisible="{Binding HasNotifications}"
Grid.Row="1" />
</Grid>
</AbsoluteLayout>
My viewmodel:
public bool HasNotifications
{
get => this.hasNotifications;
set => this.SetProperty(ref this.hasNotifications, value);
}

Answer 1

I don't think you have set the correct BindingContext. The HasNotifications is a property of your ViewModel while the BindingContext you set to your label is DashboardPageView.
I wrote a simple demo and hope you can get some idea from it:
In xaml:
<Grid
HorizontalOptions="FillAndExpand"
VerticalOptions="FillAndExpand"
AbsoluteLayout.LayoutFlags="All"
AbsoluteLayout.LayoutBounds="0,0,1,1">
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
<RowDefinition Height="*" />
<RowDefinition Height="Auto" />
<RowDefinition Height="*" />
</Grid.RowDefinitions>
<Label
Text="Title"
HorizontalOptions="Center"
VerticalOptions="Center"
TextColor="Black"
FontSize="Large"
FontAttributes="Bold"
Margin="5"
Grid.Row="0" />
<Label
Text="Notifications"
HorizontalOptions="Start"
VerticalOptions="Center"
TextColor="Black"
FontSize="Medium"
FontAttributes="Bold"
Margin="3"
IsVisible="{Binding HasNotifications}"
Grid.Row="1" />
<Button Text="change HasNotifications" Clicked="Button_Clicked" Grid.Row="2"/>
</Grid>
In cs:
public partial class MainPage : ContentPage
{
ViewModel myViewModel;
public MainPage()
{
InitializeComponent();
myViewModel = new ViewModel();
BindingContext = myViewModel;
}
private void Button_Clicked(object sender, EventArgs e)
{
myViewModel.HasNotifications = !myViewModel.HasNotifications;
}
}
public class ViewModel : INotifyPropertyChanged
{
bool _HasNotifications;
public event PropertyChangedEventHandler PropertyChanged;
public ViewModel()
{
}
public bool HasNotifications
{
set
{
if (_HasNotifications != value)
{
_HasNotifications = value;
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs("HasNotifications"));
}
}
}
get
{
return _HasNotifications;
}
}
}
Feel free to ask me any question if you have.