protected ConversationViewModel(Func <Command, bool> commandHandler, IMessageManager messageManager) : base(commandHandler)
{
this.messageManager = messageManager;
SendCommand = new MvxCommand(OnSend, () => CanSendMessage && !string.IsNullOrEmpty(EnteredText));
messageManager.CanSendMessagesChanged += () => {
SendCommand.RaiseCanExecuteChanged();
RaisePropertyChanged(nameof(CanSendMessage));
};
TogglePinCommand = new MvxCommand(() => {
SetPinned(!IsPinned);
IsPinned = !IsPinned;
});
}
public MapPageViewModel(IMvxNavigationService navigationService, IPlacesStorage placesStorage)
{
_navigationService = navigationService;
PlacesStorage = placesStorage;
SearchAddressesCommand = new MvxCommand(SearchAddresses, CanNavigateToAddressesPage);
IsInternetAccessible = Connectivity.NetworkAccess == NetworkAccess.Internet;
Connectivity.ConnectivityChanged += (sender, e) =>
{
IsInternetAccessible = e.NetworkAccess == NetworkAccess.Internet;
SearchAddressesCommand.RaiseCanExecuteChanged();
};
}
private void Validate()
{
bool hasErrorBefore = HasErrors;
_parameterError = _originalParameter == Parameter ||
string.IsNullOrEmpty(_originalParameter) && string.IsNullOrEmpty(Parameter)
? "Change parameter before update"
: null;
_applyCommand.RaiseCanExecuteChanged();
if (hasErrorBefore != HasErrors)
{
var handler = ErrorsChanged;
if (handler != null)
{
handler(this, new DataErrorsChangedEventArgs("Parameter"));
}
}
}
public void CanExecuteChanged()
{
var canExecute = false;
var command = new MvxCommand(() => { }, () => canExecute);
Assert.False(command.CanExecute());
var i = 0;
command.CanExecuteChanged += (s, e) =>
{
i++;
};
canExecute = true;
command.RaiseCanExecuteChanged();
Assert.True(command.CanExecute());
Assert.Equal(1, i);
}