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 ( 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 ( typeof (IJobWrapperService).Name); ApproveCommand = new DelegateCommand(ExecuteApproveCommand); RejectCommand = new DelegateCommand(ExecuteRejectCommand); ContainerActivities = new ContainerActivityDetailsDO(); }

Francis Bastin · Answer

Hi, Use below code to enable button dynamically. Grid.Row="2" Grid.Column="3" Height="26" Margin="5,0,5,0" Name="UpdateReport" Command="{Binding Path=UpdateReportCommand}" Content="{x:Static Member=localization:Resources.UpdateButton_Content}" IsEnabled="{Binding Path=IsUpdateMode}" Visibility="{Binding Path=IsVisible,Converter={StaticResource booleanToVisibilityConverter}}" TabIndex="3"> MVVM: ============= public bool _IsUpdateMode = false; public bool IsUpdateMode { get { return _IsUpdateMode; } set { _IsUpdateMode = value; OnPropertyChanged("IsUpdateMode"); } } private async void ExecuteCancelCommand() { this.IsUpdateMode = false; this.OnPropertyChanged("IsUpdateMode"); }

Shweta Lodha · Answer

Hi, One easiest solution can be as below. You can do few things here: 1) In IsChecked setter, you can verify if it is checked or not and based on that you can set a bool variable named CanBeApproved. This bool variable will handle enabling nad disabling of you Approve button. 2) Change ApproveCommand as: ApproveCommand = new DelegateCommand(ExecuteApproveCommand, CanApprove); where CanApprove is a method which will return CanBeApproved with a return type of bool. 3) Do changes in your XAML to read CanBeApproved.