WPF loading indicator and two buttons

Question

enter image description here HI, i need a simple thing i need two buttons , Start ,End when pressing start loading indicator appears , when pressing End it should stop thanks in advance

Answer 1

You can use ICommand-pattern , And below is a very naive example of what you need to do (hope it helps):

Your XAML - This is how you bind your buttons using the ICommand from your ViewModel:

<StackPanel>
    <local:YourCustomBusyIndicator IsBusy="{Binding IsBusy}"/>
    <Button Content="Start" Command="{Binding StartCmd}"/>
    <Button Content="End" Command="{Binding EndCmd}"/>
</StackPanel>

You ViewModel Code:

public class YourViewModel : INotifyPropertyChanged
{
    private bool _isBusy;
    public bool IsBusy
    {
        get { return _isBusy; }
        set
        {
            _isBusy = value;
            OnPropertyChanged();
        }
    }

    public RoutedCommand StartCmd { get; }
    public RoutedCommand EndCmd { get; }

    public YourViewModel()
    {
        StartCmd = new RoutedCommand(() => IsBusy = true);
        EndCmd = new RoutedCommand(() => IsBusy = false);
    }

    public event PropertyChangedEventHandler PropertyChanged;

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


//Simple implementation of ICommand
public class RoutedCommand :ICommand
{
    private readonly Action _onExecute;

    public RoutedCommand(Action onExecute)
    {
        _onExecute = onExecute;
    }
    public bool CanExecute(object parameter)
    {
        return true;
    }

    public void Execute(object parameter)
    {
        _onExecute();
    }

    public event EventHandler CanExecuteChanged;
}

Also the more standard way for the RoutedCommand will be also to pass a Func which returns a boolean as predicate to invoke on CanExecute