C# WPF: изменение кнопки Context="{Binding Text}" при нажатии

Новичок в программировании WPF. Я работаю в WinForms. У меня есть два рабочих проекта/решения WinForms, которые я хочу преобразовать в WPF. Мне удалось пройти через XMAL и MainWindowViewModel, но я уперся в стену. Проверил Интернет на наличие рабочего кода, позволяющего изменить текст «Кнопки» при нажатии. Моя проблема в том, что я не могу изменить текст контекста кнопки на что-то другое. Я хотел бы изменить текст кнопки с текущего на «Выполняется...» при нажатии, а затем, как только команда завершится, вернуться к предыдущему.

Мой XAML:

<Window x:Class = "XPR_AppBuilderSuiteWpf.MainWindow"
    xmlns = "http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x = "http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d = "http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc = "http://schemas.openxmlformats.org/markup-compatibility/2006"
    xmlns:local = "clr-namespace:XPR_AppBuilderSuiteWpf"
    mc:Ignorable = "d"
    Title = "XPR-AppBuilder Suite WPF Version" Height = "680" Width = "820">

    <Window.DataContext>
        <local:MainWindowViewModel/>
    </Window.DataContext>

    <Window.Resources>
        <Style x:Key = "GroupToggleStyle" TargetType = "RadioButton" 
        BasedOn = "{StaticResource {x:Type ToggleButton}}">
            <Setter Property = "Foreground" Value = "Blue"/>
            <Style.Triggers>
                <DataTrigger Binding = "{Binding IsErrorProcess}" 
                      Value = "True">
                    <DataTrigger.Setters>
                        <Setter Property = "Foreground" Value = "Red"/>
                    </DataTrigger.Setters>
                </DataTrigger>
            </Style.Triggers>
        </Style>
    </Window.Resources>

    <Grid Background = "Beige">
        <Grid.RowDefinitions>
            <RowDefinition Height = "250"/>
            <RowDefinition Height = "70"/>
            <RowDefinition Height = "260"/>
            <RowDefinition Height = "80"/>
        </Grid.RowDefinitions>

        <StackPanel Orientation = "Horizontal" Background = "LightBlue" Grid.Row = "0" Height = "295" Margin = "0,0,0,4">
            <GroupBox x:Name = "groupBox" Header = "AB XML Reader" Width = "778" Height = "120" Margin = "10,-160,10,14">
                <StackPanel Height = "251">
                    <Button x:Name = "btnSeletXMLFile" Content = "{Binding sSelectXMLFile}" Command = "{Binding btnSelectXMLFile}" HorizontalAlignment = "Left" 
                            Margin = "5,10,0,0" VerticalAlignment = "Top" Height = "20" Width = "76"/>
                    <Button x:Name = "btnFindTags" Content = "{Binding sFindTags}" Command = "{Binding btnFindTags}" Margin = "-452,-20,0,0" Height = "20" Width = "72"/>
                    <Button x:Name = "btnSelectFolder" Content = "{Binding sSelectFolder}" Command = "{Binding btnSelectFolder}" HorizontalAlignment = "Left" 
                            Margin = "245,-19,0,25" VerticalAlignment = "Top" Height = "20" Width = "72"/>
                    <CheckBox x:Name = "chkBCallflowXML" Content = "Run Callflow XML" IsChecked = "{Binding IschkBCallflowXML}" IsEnabled = "{Binding IsProcessingData}" 
                              HorizontalAlignment = "Left" Margin = "5,-14,0,0" VerticalAlignment = "Top" Height = "15" Width = "113"/>
                    <CheckBox x:Name = "chkBWorkspaceXML" Content = "Run Worksapce XML" IsChecked = "{Binding IschkBWorkspaceXML}" IsEnabled = "{Binding IsProcessingData}" HorizontalAlignment = "Left" Margin = "126,-14,0,0" VerticalAlignment = "Top" Height = "15" Width = "130"/>
                    <CheckBox x:Name = "chkBAppXML" Content = "Run Application XML" IsChecked = "{Binding IschkBAppXML}" IsEnabled = "{Binding IsProcessingData}" HorizontalAlignment = "Left" Margin = "268,-14,0,0" VerticalAlignment = "Top" Height = "15" Width = "131"/>
                    <CheckBox x:Name = "chkBVariablesXML" Content = "Run Variables XML" IsChecked = "{Binding IschkBVariablesXML}" IsEnabled = "{Binding IsProcessingData}" HorizontalAlignment = "Left" Margin = "407,-14,0,0" VerticalAlignment = "Top" Height = "15" Width = "125"/>
                    <CheckBox x:Name = "chkBDontAddFilename" Content = "Don't add file name" IsChecked = "{Binding IschkBDontAddFilename}" IsEnabled = "{Binding IsProcessingData}" HorizontalAlignment = "Left" Margin = "534,-14,0,0" VerticalAlignment = "Top"/>
                    <Label x:Name = "label" Content = "Filter exclusion" HorizontalAlignment = "Left" Margin = "5,6,0,0" VerticalAlignment = "Top"/>
                    <TextBox x:Name = "txtBFilter" Text = "{Binding txtBFilter}" HorizontalAlignment = "Left" Margin = "96,-20,0,0" TextWrapping = "Wrap" VerticalAlignment = "Top" Width = "120"/>
                </StackPanel>
            </GroupBox>
            <Label x:Name = "label2" Content = "Result window:" HorizontalAlignment = "Left" Margin = "-786,137,0,0" VerticalAlignment = "Top"/>
            <TextBox x:Name = "txtBResult" Text = "{Binding txtBResult}" HorizontalAlignment = "Left" Margin = "-777,164,19,0" TextWrapping = "Wrap" VerticalAlignment = "Top" Width = "762" Height = "50"/>
        </StackPanel>
        <Label x:Name = "lblStatus" Content = "Status:" Margin = "20,5,720,0" VerticalAlignment = "Top" Height = "30" Grid.Row = "1"/>
        <TextBox x:Name = "txtBStatus" Text = "{Binding txtBStatus}" Grid.Row = "1" Margin = "13,33,0,0" HorizontalAlignment = "Left" VerticalAlignment = "Top" Height = "30" Width = "777"/>
        <StackPanel Orientation = "Horizontal" Background = "LightSkyBlue" Grid.Row = "2">
            <GroupBox x:Name = "groupBox2" Header = "AB Deployed Reader"  Width = "778" Height = "200" Margin = "10,-20,10,14">
                <StackPanel >
                    <Label x:Name = "lbABDeployed" Content = "{Binding lblABDeployed}" HorizontalAlignment = "Left" Margin = "10,8,0,0" VerticalAlignment = "Top" Height = "125" Width = "743"/>
                    <Button x:Name = "btnStartABDeployedReader" Content = "{Binding sStart}" Command = "{Binding btnStartABDeployedReader}" HorizontalAlignment = "Left" Margin = "10,13,0,15" VerticalAlignment = "Center" Height = "20" Width = "50"/>
                    <Button x:Name = "btnOpenOutput" Command = "{Binding btnOpenOutput}" Content = "Open output file" Height = "20" Width = "100" Margin = "-502,-35,0,15" VerticalAlignment = "Center"/>
                    <CheckBox x:Name = "chkBSingle" Content = "Single application configuration" IsChecked = "{Binding IschkBSingle}" IsEnabled = "{Binding IsProcessingData}" Margin = "196,-33,0,0" Width = "198" HorizontalAlignment = "Left" VerticalAlignment = "Top" Height = "24"/>
                </StackPanel>
            </GroupBox>
        </StackPanel>
        <StackPanel Orientation = "Horizontal" Background = "LightCyan" Grid.Row = "3">
            <CheckBox x:Name = "chkBClearLog" Content = "Clear error log" IsChecked = "{Binding IschkBClearLog}" IsEnabled = "{Binding IsProcessingData}" HorizontalAlignment = "Left" Margin = "10,14,0,0" VerticalAlignment = "Top"/>
            <RadioButton GroupName = "btnErrorLog" Command = "{Binding btnErrorLog}" Content = "{Binding ErrorText}" Width = "80"
             Margin = "32,-25,5,5" VerticalAlignment = "Center" Style = "{StaticResource GroupToggleStyle}" Height = "20" IsEnabled = "{Binding IsError}"/>
            <Label x:Name = "lblVersion" Content = "{Binding lblVersion}" HorizontalAlignment = "Left" Margin = "-210,39,0,0" VerticalAlignment = "Top"/>
            <!--<Button x:Name = "btnError" Content = "Error Log" Command = "{Binding btnErrorLog}" HorizontalAlignment = "Left" Margin = "-92,43,0,0" VerticalAlignment = "Top" Height = "20" Width = "50"/>-->
        </StackPanel>

    </Grid>
</Window>

Моя MainWindowViewModel: (ни одна ViewModel еще не создана полностью в MVVM, используя CommunityToolkit.Mvvm). Частичный код для уменьшения объема данных.

namespace XPR_AppBuilderSuiteWpf
{
    public partial class MainWindowViewModel : ObservableRecipient
    {
        #region Variables/Fields
        private string _txtBFilter;
        private string _txtBResult;
        private string _txtBStatus;
        private string _lblVersion;
        private string _lblABDeployed;
        private bool _ischkBCallflowXML;
        private bool _ischkBWorkspaceXML;
        private bool _ischkBAppXML;
        private bool _ischkBVariablesXML;
        private bool _ischkBDontAddFilename;
        private bool _ischkBSingle;
        private bool _ischkBClearLog;
        private bool _isError;//enables the button to be clicked on else it is not enabled.
        private bool _isErrorProcess;//use to set the error button color.
        private bool _isProcessingData;//to enable or disable the checkboxes, buttons or other controls
        private string _sSelectXMLFile = string.Empty;
        private string _sFindTags = string.Empty;
        private string _sSelectFolder = string.Empty;
        private string _sStart = string.Empty;

        #endregion
        #region RelayCommands
        //aka buttons or "Commands = {Binding...}"
        public AsyncRelayCommand btnSelectXMLFile { get; set; }
        public AsyncRelayCommand btnFindTags { get; set; }
        public AsyncRelayCommand btnSelectFolder { get; set; }
        public AsyncRelayCommand btnStartABDeployedReader { get; set; }
        public AsyncRelayCommand btnOpenOutput { get; set; }
        public AsyncRelayCommand btnErrorLog { get; set; }
        #endregion
        #region Properties
        //aka textboxes, checkboxes, listboxes etc
        public bool IschkBCallflowXML
        {
            get => _ischkBCallflowXML;
            set
            {
                if (_ischkBCallflowXML == value)
                    return;
                _ischkBCallflowXML = value;
                OnPropertyChanged(nameof(IschkBCallflowXML));
            }
        }
        public bool IschkBWorkspaceXML
        {
            get => _ischkBWorkspaceXML;
            set
            {
                if (_ischkBWorkspaceXML == value)
                    return;
                _ischkBWorkspaceXML = value;
                OnPropertyChanged(nameof(IschkBWorkspaceXML));
            }
        }
        public bool IschkBAppXML
        {
            get => _ischkBAppXML;
            set
            {
                if (_ischkBAppXML == value)
                    return;
                _ischkBAppXML = value;
                OnPropertyChanged(nameof(IschkBAppXML));
            }
        }
        public bool IschkBVariablesXML
        {
            get => _ischkBVariablesXML;
            set
            {
                if (_ischkBVariablesXML == value)
                    return;
                _ischkBVariablesXML = value;
                OnPropertyChanged(nameof(IschkBVariablesXML));
            }
        }
        public bool IschkBDontAddFilename
        {
            get => _ischkBDontAddFilename;
            set
            {
                if (_ischkBDontAddFilename == value)
                    return;
                _ischkBDontAddFilename = value;
                OnPropertyChanged(nameof(IschkBDontAddFilename));
            }
        }
        public string txtBFilter
        {
            get => _txtBFilter;
            set
            {
                if (_txtBFilter == value)
                    return;
                _txtBFilter = value;
                OnPropertyChanged(nameof(txtBFilter));
            }
        }
        public string txtBResult
        {
            get => _txtBResult;
            set
            {
                if (_txtBResult == value)
                    return;
                _txtBResult = value;
                OnPropertyChanged(nameof(txtBResult));
            }
        }
        public string txtBStatus
        {
            get => _txtBStatus;
            set
            {
                if (_txtBStatus == value)
                    return;
                _txtBStatus = value;
                OnPropertyChanged(nameof(txtBStatus));
            }
        }
        public string lblABDeployed
        {
            get => _lblABDeployed;
            set
            {
                if (_lblABDeployed == value)
                    return;
                _lblABDeployed = value;
                OnPropertyChanged(nameof(lblABDeployed));
            }
        }
        public bool IschkBSingle
        {
            get => _ischkBSingle;
            set
            {
                if (_ischkBSingle == value)
                    return;
                _ischkBSingle = value;
                OnPropertyChanged(nameof(IschkBSingle));
            }
        }
        public bool IschkBClearLog
        {
            get => _ischkBClearLog;
            set
            {
                if (_ischkBClearLog == value)
                    return;
                _ischkBClearLog = value;
                OnPropertyChanged(nameof(IschkBClearLog));
            }
        }
        public bool IsProcessingData
        {
            get => _isProcessingData;
            set
            {
                if (_isProcessingData == value)
                    return;
                _isProcessingData = value;
                OnPropertyChanged(nameof(IsProcessingData));
            }
        }
        public string lblVersion
        {
            get => _lblVersion;
            set
            {
                if (_lblVersion == value)
                    return;
                _lblVersion = value;
                OnPropertyChanged(nameof(lblVersion));
            }
        }
        public bool IsError
        {
            get => _isError;
            set
            {
                if (_isError == value)
                    return;
                _isError = value;
                OnPropertyChanged(nameof(IsError));
            }
        }
        public bool IsErrorProcess
        {
            get => _isErrorProcess;
            set
            {
                if (_isErrorProcess == value)
                    return;
                _isErrorProcess = value;
                OnPropertyChanged(nameof(IsErrorProcess));
            }
        }
        public string sSelectXMLFile
        {
            get => _sSelectXMLFile;
            set
            {
                if (_sSelectXMLFile == value)
                    return;
                _sSelectXMLFile = value;
                OnPropertyChanged(nameof(sSelectXMLFile));
            }
        }
        public string sFindTags
        {
            get => _sFindTags;
            set
            {
                if (_sFindTags == value)
                    return;
                _sFindTags = value;
                OnPropertyChanged(nameof(sFindTags));
            }
        }
        public string sSelectFolder
        {
            get => _sSelectFolder;
            set
            {
                if (_sSelectFolder == value)
                    return;
                _sFindTags = value;
                OnPropertyChanged(nameof(sSelectFolder));
            }
        }
        public string sStart
        {
            get => _sStart;
            set
            {
                if (_sStart == value)
                    return;
                _sFindTags = value;
                OnPropertyChanged(nameof(sStart));
            }
        }

        //End of declarations.

        //https://stackoverflow.com/questions/76871709/using-mvvm-communitytoolkit-to-change-button-foreground-or-background
        [ObservableProperty]
        private string? errorText;
        #endregion
        public MainWindowViewModel()
        {
            txtBFilter = string.Empty;
            txtBResult = string.Empty;
            txtBStatus = string.Empty;
            lblVersion = string.Empty;
            lblABDeployed = string.Empty;
            ErrorText = "Error Log";
            IsError = false;
            IsProcessingData = true;//to enable or disable the checkboxes, buttons or other controls
            _sSelectXMLFile = "Select a XML";
            _sFindTags = "Find Tags";
            _sSelectFolder = "Select Folder";
            _sStart = "Start";

            string sTemp = System.Reflection.Assembly.GetEntryAssembly().FullName;
            Globals.sApplicationName = sTemp.Substring(0, sTemp.IndexOf(","));
            Globals.sEFApplicationName = sTemp.Substring(0, sTemp.IndexOf(","));
            string[] aSplit = sTemp.Split(',');
            lblVersion = "Version: " + aSplit[0] + " " + aSplit[1];

            #region Button initialization
            btnSelectXMLFile = new AsyncRelayCommand(OnbtnSelectXMLFileExecute, () => true);
            btnFindTags = new AsyncRelayCommand(OnbtnFindTagsExecute, () => true);
            btnSelectFolder = new AsyncRelayCommand(OnbtnSelectFolderExecute, () => true);
            btnOpenOutput = new AsyncRelayCommand(OnbtnOpenOutputExecute, () => true);
            btnStartABDeployedReader = new AsyncRelayCommand(OnbtnStartABDeployedReaderExecute, () => true);
            btnErrorLog = new AsyncRelayCommand(OnbtnErrorLogExecute, () => true);

            lblABDeployed = "This program will read an Xpressions correl or  full export file.\n\r" +
                "Then create an Excel workbook in the folder the DB was specified.\n\r" +
                "All header values/names are those of AppBuilder as seen when deployed and written to the correl.";

            // Register a message in some module
            WeakReferenceMessenger.Default.Register<StatusMessages>(this, (r, m) =>
            {
                // Handle the message here, with r being the recipient and m being the
                // input message. Using the recipient passed as input makes it so that
                // the lambda expression doesn't capture "this", improving performance.
                UpdateStatusMessage(m.Value);
            });
            #endregion
        }
        private async Task OnbtnSelectXMLFileExecute()
        {
            if (IschkBClearLog == true)
                ClearErrorLog();

            string sHold = _sSelectXMLFile, sResult = string.Empty;
            _sSelectXMLFile = "Running...";

            OpenFileDialog openFile = new OpenFileDialog();
            openFile.Multiselect = true;
            openFile.Title = "Select Application Builder XML file(s)"; //!!sets the dialog box title!!
            openFile.FileName = null;
            openFile.DefaultExt = "xml";
            openFile.Filter = "AppBuilder (*.xml)|*.xml|All files (*.*)|*.*";

            if (openFile.ShowDialog() == true)//if not true then it is cancel so skip
            {
                WeakReferenceMessenger.Default.Send(new StatusMessages($"{DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss.fff")} - Starting XML file processing."));
                ErrorFile.WriteError("======SelectXMLFile==== = ", "", 0);
                IsErrorProcess = false;

                await Task.Run(() =>
                {
                    sResult = ReadABXMLTasks.SeletXMLFileTask(IschkBDontAddFilename, openFile, IschkBCallflowXML, IschkBAppXML, IschkBVariablesXML,
                        IschkBWorkspaceXML);
                });

                //Work on this button click does not work
                if (Globals.bErrorOn == true)
                {
                    IsErrorProcess = IsErrorProcess is true;
                    IsError = true;
                }
            }
            _sSelectXMLFile = sHold;
            txtBResult = sResult;
        }

Надеюсь, этого кода достаточно. Опять же, я новичок в WPF. Показан код для кнопки «btnSelectXMLFile». Я надеюсь включить вашу помощь в работу с другими кнопками, а затем и в будущий проект.