In wpf mvvm how to get button enabled when checkbox is check

Question

this is my xaml code

<controls:ProCheckBox Grid.Row="0" Grid.Column="1" Content="{Binding CheckBoxContent, Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}"
Margin="0,5,0,5" IsChecked="{Binding IsChecked,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}" />
<controls:ProButton Content="REQUEST" HorizontalAlignment="Right" Margin="0,0,2,0" VerticalAlignment="Center"
Command="{Binding ApproveCommand,UpdateSourceTrigger=PropertyChanged,Mode=TwoWay}" BackgroundColor="MaterialBlue"
ToolTipService.ToolTip="{x:Static displayText:CommonStrings.ButtonSave}"
IsEnabled="{Binding IsChecked,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged,Converter={StaticResource BooleanToVisibilityConverter} }"
Visibility="{Binding IsRequest,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged,Converter={StaticResource BooleanToVisibilityConverter} }" >
</controls:ProButton>

this is my viewmodel

private bool _isApproval;
public bool IsApproval
{
get { return _isApproval; }
set
{
this.SetProperty(ref this._isApproval, value, "IsApproval");
}
}
private bool _isrequest;
public bool IsRequest
{
get { return _isrequest; }
set
{
this.SetProperty(ref this._isrequest, value, "IsRequest");
}
}
private bool _isChecked;
public bool IsChecked
{
get { return _isChecked; }
set { _isChecked = value; OnPropertyChanged("IsChecked"); }
}
private string _checkBoxContent;
public string CheckBoxContent
{
get { return _checkBoxContent; }
set
{
this.SetProperty(ref this._checkBoxContent, value, "CheckBoxContent");
}
}
public ICommand ApproveCommand { get; set; }
public ICommand RejectCommand { get; set; }
// public object SelectedItem { get; private set; }
private Action<bool> _dialogClosedCallback;
public async override void OnNavigatedTo(NavigationContext navigationContext)
{
_reportWrapperService = ServiceLocator.Current.GetInstance<IReportWrapperService>(typeof(IReportWrapperService).Name);
base.OnNavigatedTo(navigationContext);
var parameters = navigationContext.Parameters;
ContainersDO = parameters[AppConstants.NavigationParameterNames.Container] as ContainersDO;
ContainerAct = parameters[AppConstants.NavigationParameterNames.ContainerActivity] as ContainerActivitiesDO;
_dialogClosedCallback = navigationContext.Parameters[AppConstants.NavigationParameterNames.CallBack] as Action<bool>;
CheckBoxContent = "Draft Approved";
IsApproval = false;
if (ContainerAct.Code == "3")
{
IsApproval = true;
// IsRequest = false;
CheckBoxContent = "Request for draft approval";
}
ContainerInformationModel = new ContainerInformationViewModel();
if (ContainersDO != null)
{
}
}
public DraftCostingViewModel()
{
ContainersDO = new ContainersDO();
_jobWrapperService = ServiceLocator.Current.GetInstance<IJobWrapperService>(typeof(IJobWrapperService).Name);
ApproveCommand = new DelegateCommand(ExecuteApproveCommand);
RejectCommand = new DelegateCommand(ExecuteRejectCommand);
ContainerActivities = new ContainerActivityDetailsDO();
}