Event after button command is raised

Question

Hello,

I have a UserControl (implementing popup window) where I have a textbox and button. I have a command binded to the button, which parameter is binded from the textbox's text property.
What I want to implement, is that after command is raised I want to clear textbox's text and also hide popup itself.

I solved second problem easily with creating Click event handler (doesn't depends if command is raised inside Collapsed view), but I can't clear textbox here, because event is raised before command.

So my question is, is there some event that is raised after command or how can I implement this behaviour ?

Thank you
Lukas

Xaml code
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<UserControl    x:Class="MyApplication.CustomComponents.GetPlanNamePopup"    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"    xmlns:local="using:MyApplication.CustomComponents"    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"    mc:Ignorable="d"    d:DesignHeight="150"    d:DesignWidth="350"        x:Name="ParentPopupWindow"        xmlns:toolkit="using:WinRTXamlToolkit.Controls">    <Border        BorderThickness="2"        BorderBrush="Black"        Background="White">        <Grid>            <Grid.RowDefinitions>                <RowDefinition Height="*" />                <RowDefinition Height="2*" />            </Grid.RowDefinitions>            <toolkit:WatermarkTextBox                x:Name="PlanNameTextBox"                Margin="10" Grid.Row="0"                WatermarkText="Enter plan name..." x:Uid="EnterPlanName"                Background="White" BorderThickness="2" BorderBrush="#5c5c5c"                 Height="30" FontSize="15" MaxLength="50" TextWrapping="NoWrap" TextAlignment="Left"                VerticalContentAlignment="Stretch" HorizontalContentAlignment="Stretch" VerticalAlignment="Top"                KeyDown="TextBoxKeyDown"/>            <StackPanel                Grid.Row="1"                Orientation="Horizontal" VerticalAlignment="Center" HorizontalAlignment="Right">                <Button Margin="10" Visibility="Collapsed" Background="LightGray">                    <TextBlock FontSize="15" Margin="5" FontWeight="Bold" Foreground="Black" x:Uid="CANCEL"  Text="Cancel" HorizontalAlignment="Center" VerticalAlignment="Center" />                </Button>                <Button x:Name="SaveButton" Margin="10" Background="LightGray" Click="SaveButton_Click"                        Command="{Binding ElementName=ParentPopupWindow, Path=AddPlanCommand}"                         CommandParameter="{Binding ElementName=PlanNameTextBox, Path=Text}">                    <TextBlock FontSize="15" Margin="5" FontWeight="Bold" Foreground="Black" x:Uid="ADD" Text="Save" HorizontalAlignment="Center" VerticalAlignment="Center" />                </Button>            </StackPanel>        </Grid>    </Border></UserControl>

Code behind
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using System;using System.Collections.Generic;using System.IO;using System.Linq;using System.Runtime.InteropServices.WindowsRuntime;using System.Windows.Input;using Windows.Foundation;using Windows.Foundation.Collections;using Windows.UI.Xaml;using Windows.UI.Xaml.Controls;using Windows.UI.Xaml.Controls.Primitives;using Windows.UI.Xaml.Data;using Windows.UI.Xaml.Input;using Windows.UI.Xaml.Media;using Windows.UI.Xaml.Navigation;// The User Control item template is documented at http://go.microsoft.com/fwlink/?LinkId=234236namespace MyApplication.CustomComponents{    public sealed partial class GetPlanNamePopup : UserControl    {        public static readonly DependencyProperty AddPlanCommandProperty = DependencyProperty.Register("AddPlanCommand", typeof(ICommand), typeof(GetPlanNamePopup), new PropertyMetadata(null));        public ICommand AddPlanCommand        {            get { return GetValue(AddPlanCommandProperty) as ICommand; }            set {  SetValue(AddPlanCommandProperty, value); }        }        public GetPlanNamePopup()        {            this.InitializeComponent();        }        public void ClearTextBox()        {            this.PlanNameTextBox.Text = String.Empty;        }        private void TextBoxKeyDown(object sender, KeyRoutedEventArgs e)        {            if (e.Key == Windows.System.VirtualKey.Enter)            {                e.Handled = true;                // TODO: fake ok button click            }        }        private void SaveButton_Click(object sender, RoutedEventArgs e)        {            this.Visibility = Windows.UI.Xaml.Visibility.Collapsed;        }    }}

Answer 1

Is the text parameter and command in the ViewModel? If so, clearing the text in the viewmodel will also clear the text in the view through data binding. 

As a second option, send the textbox as a command parameter. 

Something like:

<Textbox x:Name="Mytb" Text="{Binding text}"/>

<Button Command="{Binding YourCommand}" CommandParameter="{Binding ElementName=Mytb}" />

Answer 2

In my ViewModel, there is just DelegateCommand<string> and text is passed by argument.

<toolkit:WatermarkTextBox
                x:Name="PlanNameTextBox"
                Margin="10" Grid.Row="0"
                WatermarkText="Enter plan name..." x:Uid="EnterPlanName"
                Background="White" BorderThickness="2" BorderBrush="#5c5c5c" 
                Height="30" FontSize="15" MaxLength="50" TextWrapping="NoWrap" TextAlignment="Left"
                VerticalContentAlignment="Stretch" HorizontalContentAlignment="Stretch" VerticalAlignment="Top"
                KeyDown="TextBoxKeyDown"/>

<Button x:Name="SaveButton" Margin="10" Background="LightGray" Click="SaveButton_Click"
                        Command="{Binding ElementName=ParentPopupWindow, Path=AddPlanCommand}" 
                        CommandParameter="{Binding ElementName=PlanNameTextBox, Path=Text}">

Problem is, that I don't know which event use or something to clear it after command is raised and I can't use click event, because it's raised before command.

EDIT:

I have added TextBlock which is always Collapsed. In the Click event, I copy Text from TextBox to the TextBlock. Command Argument parameter is binded from the hidden TextBlock.Text.

If someone would found better solution, I would appreciate it.