WPF Discussion Boards

Enter key invokes button click

26-Jul-16 3:47

You can call it from anywhere; it's purpose is to notify the "UI" that there is new info in the data source and the "display" needs updating.

The point is, you may have an updated data source but that does NOT imply that the UI has to also be updated at that point ... maybe the update should be deferred (for now).

For example, I have a real-time app that displays many "numbers" that are calculated; some fields on the display are based on other numbers being displayed. There is no point doing "UI updates" for each calculation ... I do all my calcs, then I call OnPropertyChanged at the end of my calc routine.

GrooverFromHolland23-Jul-16 9:44

GrooverFromHolland

23-Jul-16 9:44

Hi all,
This is my very first WPf-project, so please have some consideration and don’t advise me on MVVM .
Everything I in my project is working fine except one thing:
Whenever I hit the enter key on my keyboard a button gets the click event.
This button is not default button and the only event registered with this button is the click-event.
This is driving me insane. Confused | :confused:

If I put a breakpoint in the click event handler the routedEventsArgs e is button base click.
Here is the code related to this problem:

XML

<Style x:Key="ButtonStyle" TargetType="Button">
            <Setter Property="OverridesDefaultStyle" Value="True" />
            <Setter Property="SnapsToDevicePixels" Value="True" />
            <Setter Property="Foreground" Value="White" />
            <Setter Property="IsEnabled" Value="True" />
            <Setter Property="Width" Value="Auto" />
            <Setter Property="Height" Value="Auto" />
            <Setter Property="Margin" Value="14,5,0,5" />            
            <Setter Property="Background">
                <Setter.Value>
                    <LinearGradientBrush StartPoint="0.5,0" EndPoint="0.5,1">
                        <GradientStop Offset="0" Color="Black" />
                        <GradientStop Offset="1" Color="#FFC41B1B" />
                    </LinearGradientBrush>
                </Setter.Value>
            </Setter>
            <Setter Property="Template">
                <Setter.Value>
                    <ControlTemplate TargetType="{x:Type Button}">
                        <Grid Background="{TemplateBinding Background}">
                            <ContentPresenter x:Name="MyContentPresenter"
                                              HorizontalAlignment="Center"
                                              VerticalAlignment="Center"
                                              Content="{TemplateBinding Content}" />
                        </Grid>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
            <Style.Triggers>
                <Trigger Property="IsEnabled" Value="false">
                    <Setter Property="Foreground" Value="#7d7f74" />
                    <Setter Property="Background" Value="#31302c" />
                </Trigger>
                <Trigger Property="IsKeyboardFocused" Value="true">
                    <Setter Property="Foreground" Value="Goldenrod" />
                </Trigger>
                <Trigger Property="IsMouseOver" Value="true">
                    <Setter Property="Foreground" Value="Goldenrod" />
                </Trigger>
            </Style.Triggers>
        </Style>
        <Style x:Key="ButtonTextBlock" TargetType="TextBlock">
            <Setter Property="Foreground" Value="White" />
            <Setter Property="FontFamily" Value="Trebuchet" />
            <Setter Property="FontSize" Value="14" />
            <Setter Property="Foreground" Value="White" />
            <Setter Property="Background" Value="#000000FF" />
            <Setter Property="TextAlignment" Value="Center" />
            <Setter Property="Width" Value="95" />
            <Setter Property="Padding" Value="5" />
            <Setter Property="Margin" Value="0,8,0,8" />
            <Style.Triggers>
                <Trigger Property="IsMouseOver" Value="true">
                    <Setter Property="Foreground" Value="Goldenrod" />
                </Trigger>
                <Trigger Property="IsEnabled" Value="false">
                    <Setter Property="Foreground" Value="#7d7f74" />
                    <Setter Property="Background" Value="#31302c" />
                </Trigger>
            </Style.Triggers>
        </Style>
        <Style x:Key="TextBoxTextBlock" TargetType="TextBlock">
            <Setter Property="Foreground" Value="White" />
            <Setter Property="FontFamily" Value="Trebuchet" />
            <Setter Property="FontSize" Value="14" />
            <Setter Property="Foreground" Value="White" />
            <Setter Property="Background" Value="#000000FF" />
            <Setter Property="TextAlignment" Value="Center" />
            <Setter Property="Width" Value="80" />
            <Setter Property="Padding" Value="5" />
            <Setter Property="Margin" Value="0,8,0,8" />
            <Setter Property="Height" Value="Auto" />
            <Style.Triggers>
                <Trigger Property="IsEnabled" Value="false">
                    <Setter Property="Foreground" Value="#7d7f74" />
                    <Setter Property="Background" Value="#31302c" />
                </Trigger>
            </Style.Triggers>
        </Style>

And:

XML

<Button x:Name="buttonReset"
                   Click="buttonReset_Click"
                   Style="{StaticResource ButtonStyle}">
               <TextBlock Style="{StaticResource ButtonTextBlock}">
                   <Run Text="Reset" />
                   <LineBreak /><Run Text="alles" />
               </TextBlock>
           </Button>

code behind:

private void buttonReset_Click(object sender, RoutedEventArgs e)
      {
          if (!buttonReset.IsKeyboardFocused) return;
          ResetAll();
          buttonNwOpdrNr.IsEnabled = true;
          buttonZoeken.IsEnabled = true;
      }

What can cause this behavior ?

Thanks in advance,

Groover

0200 A9 23
0202 8D 01 80
0205 00

Re: Enter key invokes button click

Mycroft Holmes23-Jul-16 14:28

Re: Enter key invokes button click

23-Jul-16 14:28

If your button has the focus then enter will invoke the click event.

If all other controls are read only then your button may automatically get the focus.

Never underestimate the power of human stupidity
RAH

GrooverFromHolland24-Jul-16 0:19

GrooverFromHolland

24-Jul-16 0:19

Thank You for Your reply, now it is obvious that the button automatically gets focus, but I could not see difference in appearance of the button. I'll fix that.
How can I prevent any control to get keyboard focus other than with the TAB-key or mouse-click?
It is a disaster when my application gets a reset when the ENTER-key is accidentally hit.

0200 A9 23
0202 8D 01 80
0205 00

Re: Enter key invokes button click

Mycroft Holmes24-Jul-16 14:34

Using negative height margin values to properly vertically align a control

24-Jul-16 14:34

Take a look into the FocusManager, this is my primary grid declaration.

XML

<Grid Style="{StaticResource InfoGrid}"
                FocusManager.FocusedElement="{Binding ElementName=txtAuthoriser}">

Never underestimate the power of human stupidity
RAH

Stephen Holdorf22-Jul-16 14:22

Re: Using negative height margin values to properly vertically align a control

22-Jul-16 14:22

I created a grid based XAML page. In the grid I display images which require no negative top margin, vertical, values. In my page I have two labels in textblocks that will not align properly in their grid stack panel with out using negative top margin values in the textblocks. The first label textblock I have to use a Margin="0,-35,0,0" and the second I have to use Margin="0, -650, 0, 0. The XAML is below. One final thing. After what you see I need a table to display labels in several rows and columns. Each row might have different width columns. In my design what is recommended for that?

XAML

<Window
    x:Class="MasterPage.ApplicationInfoWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:v="clr-namespace:MasterPage"
    Title="Intake 4" Height="900" Width="1000" Background="#FFD9DDE8">
    <DockPanel>
        <Grid>
            <Grid.RowDefinitions>
                <RowDefinition Height="*"/>
                <RowDefinition Height="*"/>
                <RowDefinition Height="*"/>
            </Grid.RowDefinitions>
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="*"/>
                <ColumnDefinition Width="*"/>

            </Grid.ColumnDefinitions>
        </Grid>
        <StackPanel >
                <Border Margin="0, 0, 0, 0" BorderBrush="Black" BorderThickness="1">
                <StackPanel Height="133" VerticalAlignment="Top" Grid.Row="0" Grid.Column="0" Grid.ColumnSpan="2">

                    <StackPanel>
                        <Image Source="Images\header.jpg" Stretch="Fill" DockPanel.Dock="Top" Height="47"  />
                    </StackPanel>

                    <StackPanel Margin="3,0,0,5" HorizontalAlignment="Left">
                        <Image Source="Images\DSPASS_logo.png" Width="324" Stretch="Fill" DockPanel.Dock="Top" Height="80" />
                    </StackPanel>
                    <StackPanel DockPanel.Dock="Top" HorizontalAlignment="Right" >
                        <TextBlock FontSize="15" TextWrapping="WrapWithOverflow" Height="25" Margin="0,-35,0,0" >
                 <Label FontSize="10" HorizontalContentAlignment="Right"  HorizontalAlignment="Right" Name="Namelabel" Width="230" FontWeight="Bold" Foreground="#1664A1" Content="Name"/>
                        </TextBlock>
                    </StackPanel>
        </StackPanel>

        </Border>

        <Border Margin="0, 0, 0, 0" BorderBrush="Black" BorderThickness="1">

                <StackPanel Background="wHITE" Height="358" VerticalAlignment="Top" Grid.Column="0" Grid.ColumnSpan="2" Grid.Row="1">
                    <StackPanel>
                    <Image Source="Images\silhouette.jpg" VerticalAlignment="Top"    HorizontalAlignment="Left" Width="320" Stretch="Fill" DockPanel.Dock="Top" Height="360" />
                </StackPanel>
                    <StackPanel VerticalAlignment="Top" >
                        <TextBlock FontSize="15"  HorizontalAlignment="Right" Height="75" Margin="0, -650, 0, 0"  TextWrapping="WrapWithOverflow" >
                 <Label FontSize="35" HorizontalContentAlignment="Left"   Name="Namelabel2" Width="640" FontWeight="Bold" Foreground="#1664A1" Content="Name"/>
                    </TextBlock>
                </StackPanel>
                    </StackPanel>
        </Border>
        </StackPanel>


    </DockPanel>
</Window>

modified 23-Jul-16 8:09am.

Stephen Holdorf23-Jul-16 4:50

Re: Using negative height margin values to properly vertically align a control

23-Jul-16 4:50

I did find an answer to my question by just modifying a couple of properties and adding a new stack panel. As you can see new stackpanels were added using the attribute Orientation="Horizontal. So the grid now works without adding negtive margin values. Now the only thing I'm working on is trying to add a table sub grid as mentioned above. If anyone has any ideas there that would help. Thanks.

HTML

<Window
    x:Class="MasterPage.ApplicationInfoWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:v="clr-namespace:MasterPage"
    Title="Intake 4" Height="900" Width="1000" Background="#FFD9DDE8">
    <DockPanel>
        <Grid>
            <Grid.RowDefinitions>
                <RowDefinition Height="*"/>
                <RowDefinition Height="*"/>
                <RowDefinition Height="*"/>
            </Grid.RowDefinitions>
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="*"/>
                <ColumnDefinition Width="*"/>

            </Grid.ColumnDefinitions>
        </Grid>
        <StackPanel >
                <Border Margin="0, 0, 0, 0" BorderBrush="Black" BorderThickness="1">
                <StackPanel Height="133" VerticalAlignment="Top" Grid.Row="0" Grid.Column="0" Grid.ColumnSpan="2">

                    <StackPanel>
                        <Image Source="Images\header.jpg" Stretch="Fill" DockPanel.Dock="Top" Height="47"  />
                    </StackPanel>
                    <StackPanel Orientation="Horizontal">
                    <StackPanel Margin="3,0,0,5" HorizontalAlignment="Left">
                        <Image Source="Images\DSPASS_logo.png" Width="324" Stretch="Fill" DockPanel.Dock="Top" Height="80" />
                    </StackPanel>
                    <StackPanel HorizontalAlignment="Right" Margin="400, 0, 0, 0" >
                        <TextBlock FontSize="15" TextWrapping="WrapWithOverflow" Height="25" Margin="0,60,0,0" >
                 <Label FontSize="10" HorizontalContentAlignment="Right"  HorizontalAlignment="Right" Name="Namelabel" Width="230" FontWeight="Bold" Foreground="#1664A1" Content="Name"/>
                        </TextBlock>
                    </StackPanel>
                    </StackPanel>
                    </StackPanel>

        </Border>

        <Border Margin="0, 0, 0, 0" BorderBrush="Black" BorderThickness="1">

                <StackPanel Background="wHITE" Orientation="Horizontal" Height="358" VerticalAlignment="Top" Grid.Column="0" Grid.ColumnSpan="2" Grid.Row="1">
                    <StackPanel>
                    <Image Source="Images\silhouette.jpg" VerticalAlignment="Top"    HorizontalAlignment="Left" Width="320" Stretch="Fill" DockPanel.Dock="Top" Height="360" />
                </StackPanel>
                    <StackPanel>
                        <TextBlock FontSize="15"  HorizontalAlignment="Right" Height="75">
                 <Label FontSize="35" HorizontalContentAlignment="Left"   Name="Namelabel2" Width="640" FontWeight="Bold" Foreground="#1664A1" Content="Name"/>
                    </TextBlock>
                </StackPanel>
                    </StackPanel>
        </Border>
        </StackPanel>


    </DockPanel>
</Window>

Stephen Holdorf23-Jul-16 9:47

Re: List Control Question

23-Jul-16 9:47

After doing a lot of research I found the answer to my problem. See the code below. I now understand a lot more about XAML then I did before. From the code below I now know how to do the upper portion of my page but am lost about how to finish my page.Now my confusion is the bottom part of my page needs to be as set of several vertically tables, two per row, with headers and three columns per table. I think that I need to use grids to do this but still am not sure. If someone could point me in the right direction that would be great.

HTML

<Window
    x:Class="MasterPage.ApplicationInfoWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:v="clr-namespace:MasterPage"
    Title="Intake 4" Height="900" Width="1000" Background="#FFD9DDE8">
    <StackPanel>
        <Border Margin="0, 0, 0, 0" BorderBrush="Black" BorderThickness="1">
            <StackPanel Height="133" VerticalAlignment="Top">
                <Image Source="Images\header.jpg" Stretch="Fill" Height="47"  />
                <DockPanel Margin="3,0,0,5">
                    <Image DockPanel.Dock="Left" Source="Images\DSPASS_logo.png" Width="324" Stretch="Fill" Height="80" />
                    <Label DockPanel.Dock="Right" FontSize="10" HorizontalContentAlignment="Right"  HorizontalAlignment="Right" VerticalAlignment="Bottom" Name="Namelabel" Width="230" FontWeight="Bold" Foreground="#1664A1" Content="Name"/>
                </DockPanel>
            </StackPanel>
        </Border>    
        <Border Margin="0, 0, 0, 0" BorderBrush="Black" BorderThickness="1">
            <DockPanel Background="White" Height="358" VerticalAlignment="Top">
                <Image DockPanel.Dock="Left" Source="Images\silhouette.jpg" VerticalAlignment="Top" HorizontalAlignment="Left" Width="320" Stretch="Fill" Height="360" />
                <Label DockPanel.Dock="Right" FontSize="35" HorizontalContentAlignment="Left" Name="Namelabel2" Width="640" FontWeight="Bold" Foreground="#1664A1" Content="Name"/>
            </DockPanel>
        </Border>
    </StackPanel>
</Window>

List Control Question

Kevin Marois21-Jul-16 14:36

Kevin Marois

21-Jul-16 14:36

I'm creating a List type of control[^].

The ListBox's DataTemplate will be an Expander.

Each Expander will have UserControls added to it from the code behind at runtime. How do I ensure that the control is added to the correct Expander?

Thanks

If it's not broken, fix it until it is

Gerry Schmitz22-Jul-16 11:18

Keeping correct layout when browser is resized

22-Jul-16 11:18

Track each Expander's control reference.

Stephen Holdorf17-Jul-16 3:37

Re: Keeping correct layout when browser is resized

17-Jul-16 3:37

I have a XAML window that the layout is done using a main grid. The problem is when the browser is resized the controls in the second and third columns move to the right and the window's layout is no longer correct. I have pasted the XAML below. I think the layout of a WPF window should be grid based with all controls residing in the window's master grid. Is this the proper layout design for WPF or is there a different recommended layout pattern? Also, I find myself having to use negative value in margins. This confuses me greatly as well.

XML

<Window x:Class="MasterPage.Intake1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:v="clr-namespace:MasterPage.View"
    Title="Intake 1" Height="900" Width="1000" Background="#FFD9DDE8" >
        <Grid>
            <Grid.RowDefinitions>
                <RowDefinition Height="35*"/>
                <RowDefinition Height="45*"/>
                <RowDefinition Height="190*"/>
                <RowDefinition Height="275*"/>
        </Grid.RowDefinitions>
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="500*"/>
                <ColumnDefinition Width="300*"/>
                <ColumnDefinition Width="250*"/>
            </Grid.ColumnDefinitions>
            
       <StackPanel Grid.Column="0" Grid.ColumnSpan="3" Grid.Row="0">
            <Image Source="Images\header.jpg" Height="47" Margin="0,0,0,0" />
      </StackPanel>
      <StackPanel HorizontalAlignment="Left" Grid.Column="0" Height="80"  Width="350" Grid.ColumnSpan="1" Grid.Row="1"  Margin="0,-23,0,0">
            <Image Source="Images\DSPASS_logo.png" Stretch="Fill" DockPanel.Dock="Top" Height="70" />
      </StackPanel>
        <StackPanel Grid.Column="4" Grid.Row="1" Grid.ColumnSpan="1" Margin="0,0,0,0">
        <TextBlock FontSize="15" Margin="0,0,0,0" Height="25" Width="300" TextWrapping="WrapWithOverflow">
            <Label FontSize="10" Name="Namelabel" Width="250" FontWeight="Bold" Foreground="#1664A1" Content="Welcome to DS PASS:"/>               
        </TextBlock>
      </StackPanel>
        <StackPanel Grid.Column="0" Grid.Row="2" HorizontalAlignment="Left" Margin="10,10,0,0" Height="290" Width="975" VerticalAlignment="Top" Grid.ColumnSpan="3" Grid.RowSpan="1">
            <Label Height="36" FontSize="16" Content="Post Identification" Background="#FF014E7E" FontWeight="Bold" Foreground="White" Margin="-5,0,-18,0"/>
            <StackPanel x:Name="_wordLength" Orientation="Horizontal" Margin="235,0,200,0">
                <TextBlock Height="20" x:Name="ApplicantType_TextBlock" Text="Applicant Type" Width="110" Margin="5" TextAlignment="Right"/>
                <ComboBox Height="25" x:Name="textBoxWordLength" Width="400" Margin="10,5"/>
            </StackPanel>
            <StackPanel x:Name="_integerWordLength" Orientation="Horizontal" Margin="235,0,200,0">
                <TextBlock Height="20" x:Name="textBlockIntegerWordLength" Text="Person Type" Width="110" Margin="5" TextAlignment="Right"/>
                <ComboBox Height="25" x:Name="textBoxIntegerWordLength" Width="400" Margin="10,5"/>
            </StackPanel>
            <StackPanel x:Name="_Post" Orientation="Horizontal" Margin="235,0,200,20">
                <TextBlock Height="20" x:Name="Post_TextBlock" Text="Post" Width="110" Margin="5" TextAlignment="Right"/>
                <ComboBox Height="25" x:Name="Post_TextBox" Width="400" Margin="10,5"/>
            </StackPanel>
        </StackPanel>
        <StackPanel Grid.Column="0" Grid.Row="3" HorizontalAlignment="Left" Height="130" Margin="15,-120,0,0" VerticalAlignment="Top" Grid.ColumnSpan="3" >
            <Label Height="36" FontSize="16" Content="Applicant Employment" Background="#FF004A78" FontWeight="Bold" Foreground="White" Margin="-5,0,-18,0"/>
                    <StackPanel x:Name="_max1" Orientation="Vertical" Margin="1,0,355,0">
                        <TextBlock Height="20" x:Name="maxTextBlock1" Text="Employee ID" Width="100" Foreground="Black" Margin="0,15,459,5" TextAlignment="Right"/>
                        <TextBox Height="25" x:Name="maxTextBox1" Width="400" Margin="0,-5,90,25"/>
                    </StackPanel>
        </StackPanel>
        <StackPanel Grid.Column="0" Grid.Row="4" Grid.ColumnSpan="3" Orientation="Vertical" HorizontalAlignment="Left" Height="330" Margin="0,10,0,0" VerticalAlignment="Top" Width="965" Grid.RowSpan="2">
                <Label Height="36" FontSize="16" Content="English Version of Name" Background="#FF005183" Grid.Row="4" FontWeight="Bold" Margin="10,10,0,0" Foreground="White" Padding="4,5,5,5"/>
                    <StackPanel x:Name="_LastName" Orientation="Vertical">
                    <TextBlock Height="20" x:Name="LastName_TextBlock" Text="Last Name/Surname" Margin="55,5,459,5" TextAlignment="Left"/>
                    <TextBox Height="25" x:Name="LastName_TextBox" Width="500" Margin="55,5,459,5"/>
                    </StackPanel>
                    <StackPanel x:Name="_FirstName" Orientation="Vertical">
                    <TextBlock Height="20" x:Name="FirstName_TextBlock" Text="First Name" Margin="55,0,459,0" TextAlignment="Left"/>
                    <TextBox Height="25" x:Name="FirstName_TextBox" Width="500" Margin="55,0,459,0"/>
                    </StackPanel>
                    <StackPanel x:Name="_MiddleName" Orientation="Vertical">
                        <TextBlock Height="20" x:Name="MiddleName_TextBlock" Text="Middle Name" Margin="55,5,459,5" TextAlignment="Left"/>
                    <TextBox Height="25" x:Name="MiddleName_TextBox" Width="500" Margin="55,5,459,5"/>
                    </StackPanel>
                    <StackPanel x:Name="_ExtendedName" Orientation="Vertical">
                        <TextBlock Height="20" x:Name="ExtendedName_TextBlock" Text="Extended name (Tribal, Jr., III, etc.)" Margin="55,5,372,5" TextAlignment="Left"/>
                    <TextBox Height="25" x:Name="Extended_TextBox" Width="500" Margin="55,5,459,5"/>
                    </StackPanel>
                </StackPanel>
                <StackPanel Grid.RowSpan="4" Grid.Column="4" HorizontalAlignment="Left" Height="230" Margin="-250,400,0,0" Width="480" Grid.ColumnSpan="1">
                    <StackPanel x:Name="_Aliases" Orientation="Vertical" Margin="-15,0,0,0" Height="144">
                        <TextBlock Height="20" x:Name="Aliases_TextBlock" Text="Aliases" Margin="40,-5,0,5" TextAlignment="Left"/>
                        <TextBox Height="25" x:Name="Aliases_TextBox" Width="500" Margin="43,5"/>
                        <TextBox Height="25" x:Name="Aliases_TextBox1" Width="500" Margin="43,5"/>
                        <TextBox Height="25" x:Name="Aliases_TextBox2" Width="500" Margin="43,5"/>
                    </StackPanel>
        </StackPanel>

        <!--<Label HorizontalAlignment="Left" Margin="4,132,0,0" Grid.Row="3" VerticalAlignment="Top" Background="#FF72C772" Grid.ColumnSpan="3" Width="1242" Height="36"/>
        <Button Content="Continue" Grid.Column="2" HorizontalAlignment="Left" Margin="16,139,0,0" Grid.Row="3" VerticalAlignment="Top" Width="125" Click="Page1_Continue_Click"/>
        <Button Content="Save Draft" Grid.Column="1" HorizontalAlignment="Left" Margin="336,139,0,0" Grid.Row="3" VerticalAlignment="Top" Width="125"/>-->
        <Label HorizontalAlignment="Left" Margin="4,400,0,0" Grid.Row="4" VerticalAlignment="Top" Background="#FF52BB52" Grid.ColumnSpan="3" Width="983" Height="36">
        </Label>
        <Button Content="Save Draft" Grid.Column="1" HorizontalAlignment="Left" Margin="150,408,0,0" Grid.Row="5" VerticalAlignment="Top" Width="125" />
        <Button x:Name="ContinueButton_Page2" Content="Continue" Grid.Column="1"  Width="125" Grid.Row="5" VerticalAlignment="Top"  Margin="200,408,0,0" Grid.ColumnSpan="2" Click="btnContinue_Click"/>
    </Grid>
</Window>

modified 17-Jul-16 10:51am.

Gerry Schmitz18-Jul-16 6:19

Styling a Drag and Drop Items behavior in a WPF ListView

18-Jul-16 6:19

WPF works for you when your "view" is laid out in a logical manner; yours is not; it is particularly obvious if you look at your XAML in the "document outline" and "design" windows.

StackPanels are hard to control; it's easier / more intuitive using "Grids within Grids".

You should not be altering "heights" and "margins" (from their defaults) to affect positioning; the "styles" (i.e. height, width, etc.) of the individual controls should drive the (automatic) layout.

Start by removing the height and width of the window and look at the properties that relate to its content; e.g. StartupLocation; SizeToContent; WindowState; etc.

Kenneth Haugland13-Jul-16 5:43

Kenneth Haugland

13-Jul-16 5:43

So, I basically took the reordering from Josh Smith:
Drag and Drop Items in a WPF ListView[^]
All I wanted to do now was to draw a line where the new item was inserted, with an arrow. Like the old WinForms style behavior:
Manual reordering of items inside a ListView[^]

The line under was easy to achieve, all I had to was to alter the Style:

HTML

<Style x:Key="ItemContStyle" TargetType="ListViewItem">
          <Style.Resources>
              <LinearGradientBrush x:Key="MouseOverBrush" StartPoint="0.5, 0" EndPoint="0.5, 1">
                  <GradientStop Color="#22000000" Offset="0" />
                  <GradientStop Color="#44000000" Offset="0.4" />
                  <GradientStop Color="#55000000" Offset="0.6" />
                  <GradientStop Color="#33000000" Offset="0.9" />
                  <GradientStop Color="#22000000" Offset="1" />
              </LinearGradientBrush>

              <SolidColorBrush x:Key="SelectedBackgroundBrush" Color="#DDD" />
              <SolidColorBrush x:Key="DisabledForegroundBrush" Color="#888" />
          </Style.Resources>

          <Setter Property="Padding" Value="0,4" />
    <Setter Property="HorizontalContentAlignment" Value="Stretch" />
    <!-- The default control template for ListViewItem has a Border
         which contains the item's content. -->
    <Setter Property="Border.BorderThickness" Value="0,0,0,0.5" />
          <Setter Property="Border.BorderBrush" Value="Transparent"/>
    <!-- These triggers react to changes in the attached properties set
         during a managed drag-drop operation. -->
    <Style.Triggers>
      <Trigger Property="jas:ListViewItemDragState.IsBeingDragged" Value="True">
        <Setter Property="FontWeight" Value="DemiBold" />
      </Trigger>
      <Trigger Property="jas:ListViewItemDragState.IsUnderDragCursor" Value="True">
                  <Setter Property="Border.BorderThickness" Value="0,0,0,0.5" />
                  <Setter Property="Border.BorderBrush" Value="Red"/>
              </Trigger>
    </Style.Triggers>
  </Style>

SO I looked at the ControlTemplate for the ListViewItems:
ListViewItem ControlTemplate Example[^]

But as soon as I started to add the ControlTemplate Design the correct behavior stopped:

HTML

<Style x:Key="ItemContStyle" TargetType="ListViewItem">
          <Style.Resources>
              <LinearGradientBrush x:Key="MouseOverBrush" StartPoint="0.5, 0" EndPoint="0.5, 1">
                  <GradientStop Color="#22000000" Offset="0" />
                  <GradientStop Color="#44000000" Offset="0.4" />
                  <GradientStop Color="#55000000" Offset="0.6" />
                  <GradientStop Color="#33000000" Offset="0.9" />
                  <GradientStop Color="#22000000" Offset="1" />
              </LinearGradientBrush>

              <SolidColorBrush x:Key="SelectedBackgroundBrush" Color="#DDD" />
              <SolidColorBrush x:Key="DisabledForegroundBrush" Color="#888" />
          </Style.Resources>

          <Setter Property="Template">
              <Setter.Value>
                  <ControlTemplate TargetType="ListViewItem">
                          <Grid>
                          <Polygon
                              x:Name="poly_PART"
                              VerticalAlignment="Bottom"
                              HorizontalAlignment="Left"
                              Stroke="Red"
                              Fill="Red"
                              StrokeThickness="2"
                              Points="0,1 0,-1 1,0"
                              Margin="0,0,0,0"
                              Width="10"
                              Height="10"
                              Stretch="Fill"
                              />
                          <ContentPresenter
                              Content="{TemplateBinding Content}"
                              HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"
                              VerticalAlignment="{TemplateBinding VerticalContentAlignment}"
                              SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" />
                          </Grid>
                  </ControlTemplate>
              </Setter.Value>
          </Setter>

          <Setter Property="Padding" Value="0,4" />
    <Setter Property="HorizontalContentAlignment" Value="Stretch" />
    <!-- The default control template for ListViewItem has a Border
         which contains the item's content. -->
    <Setter Property="Border.BorderThickness" Value="0,0,0,0.5" />
          <Setter Property="Border.BorderBrush" Value="Transparent"/>
    <!-- These triggers react to changes in the attached properties set
         during a managed drag-drop operation. -->
    <Style.Triggers>
      <Trigger Property="jas:ListViewItemDragState.IsBeingDragged" Value="True">
        <Setter Property="FontWeight" Value="DemiBold" />
      </Trigger>
      <Trigger Property="jas:ListViewItemDragState.IsUnderDragCursor" Value="True">
        <!--<Setter Property="Background" Value="{StaticResource MouseOverBrush}" />-->
                  <Setter Property="Border.BorderThickness" Value="0,0,0,0.5" />
                  <Setter Property="Border.BorderBrush" Value="Red"/>
              </Trigger>
    </Style.Triggers>
  </Style>

How do I fix this issue?

Short way defining a property with the NotifyPropertyChanged() call

Mc_Topaz9-Jul-16 9:26

Mc_Topaz

9-Jul-16 9:26

Here is a common way of having a ViewModel's property with the INotifyPropertyChanged interface:

string text;
public string Text
{
    get { return text; }
    set
    {
        if (value != text)
        {
            text = value;
            NotifyPropertyChanged(nameof(Text));
        }
    }
}

This occupies one line for the member variable and twelve lines for the property.
In my ViewModel I have many properties and the code is getting very huge due to each property need the above body to include the NotifyPropertyChanged method and a member varible.

I prefer my properties to be defined in this way:

public string Text { get; set; }

That property's body is just one line and I don't need to define a member variable.
But I cannot find out how to call the NotifyPropertyChanged method.

Is there a solution to short the body of the property and still have the call to the NotifyPropertyChanged method?

For instance:
* Having a property without the need of a member variable.
* Define the property as close as possible to: public string Text { get; set; }.
* Having the call to the NotifyPropertyChanged in the setter body.

Best regards,
/Steffe

Re: Short way defining a property with the NotifyPropertyChanged() call

Mycroft Holmes9-Jul-16 11:35

Re: Short way defining a property with the NotifyPropertyChanged() call

9-Jul-16 11:35

Mc_Topaz wrote:
Is there a solution to short the body of the property and still have the call to the NotifyPropertyChanged method?

No.

Never underestimate the power of human stupidity
RAH

Mc_Topaz9-Jul-16 11:49

Mc_Topaz

9-Jul-16 11:49

Got this working with PropertyChanged.Fody NuGet package.

Read how here:
Dotnet by Example: Using Fody.PropertyChanged for automatic PropertyChangedEvents and model-to-viewmodel communication[^]

Install the NuGet packet in Visual Studio NuGet: Packet Manager Console:
Command: Install-Package PropertyChanged.Fody

Re: Short way defining a property with the NotifyPropertyChanged() call

Super Lloyd10-Jul-16 14:31

Super Lloyd

10-Jul-16 14:31

No.

However you can make your declaration easier by using Code Snippets[^].

Here is my MVVM property snippet

XML

<?xml version="1.0" encoding="utf-8"?>
<CodeSnippets xmlns="http://schemas.microsoft.com/VisualStudio/2005/CodeSnippet">
  <CodeSnippet Format="1.0.0">
    <Header>
      <SnippetTypes>
        <SnippetType>Expansion</SnippetType>
      </SnippetTypes>
      <Title>SnippetFile1</Title>
      <Author>Lloyd</Author>
      <Description>INotifyPropertChanged property</Description>
      <HelpUrl>
      </HelpUrl>
      <Shortcut>propn</Shortcut>
    </Header>
    <Snippet>
      <Declarations>
        <Object Editable="true">
          <ID>Type</ID>
          <ToolTip>Type</ToolTip>
          <Default>object</Default>
          <Function>
          </Function>
          <Type>
          </Type>
        </Object>
        <Literal Editable="true">
          <ID>Property</ID>
          <ToolTip>Property</ToolTip>
          <Default>Property</Default>
          <Function>
          </Function>
        </Literal>
      </Declarations>
      <Code Language="csharp"><![CDATA[#region $Property$

        public $Type$ $Property$ 
        {
            get { return m$Property$; }
            set
            {
                if (value == m$Property$)
                    return;

                m$Property$ = value;
                OnPropertyChanged();
            }
        }
        $Type$ m$Property$;

        #endregion]]></Code>
    </Snippet>
  </CodeSnippet>
</CodeSnippets>

A new .NET Serializer
All in one Menu-Ribbon Bar
Taking over the world since 1371!

Re: Short way defining a property with the NotifyPropertyChanged() call

Pete O'Hanlon10-Jul-16 21:23

Pete O'Hanlon

10-Jul-16 21:23

There is a way to do this, but it requires an extra bit of build infrastructure. You can, relatively easily, use an AOP (aspect-oriented programming) solution like PostSharp[^] or you could use a Roslyn analyzer/generator[^].

This space for rent

Re: Short way defining a property with the NotifyPropertyChanged() call

Gerry Schmitz11-Jul-16 6:04

Re: Short way defining a property with the NotifyPropertyChanged() call

11-Jul-16 6:04

The "notify patterns" used in this case are "standard"; but not necessarily THE ONLY way.

If performance is not any issue, and UI updates are localized (usually), then simply issue a "NotifyPropertyChanged(string.Empty)" and the "UI engine" will "refresh" ALL output fields.

Used judiciously, it can make more sense to do "notifications" from your main logic than within a "setter"; particularly when it comes to real-time updates that reference multiple "outputs" for computing other outputs.

As an alternative, one can "queue" names of properties that were changed, remove duplicates, then pump them through a notify call; if that fits.

You can then leave the properties as automatic gets and setters.

Benchmark.

Kenneth Haugland13-Jul-16 4:12

Kenneth Haugland

13-Jul-16 4:12

I usually do this (took the code from somwhere but I cant remember the referance):

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.ComponentModel;
using System.Runtime.CompilerServices;
using System.Windows;

    /// <summary>
    ///     Implementation of <see cref="INotifyPropertyChanged" />  and Frameworkelement to simplify base drawing classes.
    /// </summary>
    public abstract class NotifierBase : INotifyPropertyChanged
    {
        /// <summary>
        ///     Multicast event for property change notifications.
        /// </summary>
        public event PropertyChangedEventHandler PropertyChanged;

        /// <summary>
        ///     Checks if a property already matches a desired value.  Sets the property and
        ///     notifies listeners only when necessary.
        /// </summary>
        /// <typeparam name="T">Type of the property.</typeparam>
        /// <param name="storage">Reference to a property with both getter and setter.</param>
        /// <param name="value">Desired value for the property.</param>
        /// <param name="propertyName">
        ///     Name of the property used to notify listeners.  This
        ///     value is optional and can be provided automatically when invoked from compilers that
        ///     support CallerMemberName.
        /// </param>
        /// <returns>
        ///     True if the value was changed, false if the existing value matched the
        ///     desired value.
        /// </returns>
        protected bool SetProperty<T>(ref T storage, T value, [CallerMemberName] string propertyName = null)
        {

            if (Equals(storage, value))
            {
                return false;
            }

            storage = value;
            this.OnPropertyChanged(propertyName);
            return true;
        }

        /// <summary>
        ///     Notifies listeners that a property value has changed.
        /// </summary>
        /// <param name="propertyName">
        ///     Name of the property used to notify listeners.  This
        ///     value is optional and can be provided automatically when invoked from compilers
        ///     that support <see cref="CallerMemberNameAttribute" />.
        /// </param>
        protected void OnPropertyChanged([CallerMemberName] string propertyName = null)
        {
            this.PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
        }
    }

Then I simply call it like this:

private string m_Name ="";
public string Name
{
    get { return m_Name; }
    set
    {
        SetProperty(ref m_Name, value);
    }
}

I just have a custom snippet to deal with the proeprty coding.

Re: Short way defining a property with the NotifyPropertyChanged() call

Mycroft Holmes13-Jul-16 12:54

Add column sorting to a WPF grid

13-Jul-16 12:54

I applaud your construction but to save 1 if statement and 1 line of code. You ROI is minimal Laugh | :laugh:

I use a snippet for the entire property structure and a region surrounding all the properties. Saving half a dozen lines of code per property is just not that high on my todo list.

Never underestimate the power of human stupidity
RAH

Stephen Holdorf7-Jul-16 7:11