Animation in visibility from hidden to collapsed and vice versa

Question

I am trying to achieve something similar to iPhone message view. On a button click, a delete button would slide out for every message and on clicking \"done\" the delete buttons

Answer 1

Old question... huh...

Anyway... forget about visibility. The trick is to animate Width/Height of the Control placed in Grid's Column/Row where the Column/Row has Width set to Auto. Uff :)

So here is a Grid named "container" with two columns. In the first column can be placed whatever you want, but you should align it to Right since you want it to move when your delete button is displayed. And in the second column there is a Control (representing your DeleteButton) Notice that first column has Width="*" and second column has Width="Auto"

<Grid Background="Purple" Width="350" Height="100">
    <CheckBox Content="Show" IsChecked="{Binding Path=ShowDeleteButton}" Height="16" HorizontalAlignment="Left" Margin="12,12,0,0" Name="checkBox1" VerticalAlignment="Top" />
    <Grid x:Name="container" Margin="40,0,0,0">
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="*"/>
            <ColumnDefinition Width="Auto"/>
        </Grid.ColumnDefinitions>
        <Grid Name="content" Margin="0">
            <Label Content="Look I'm flyin'!" Margin="0,30,10,0" VerticalAlignment="Top" HorizontalAlignment="Right"/>
        </Grid>
        <Control Grid.Column="1" Margin="0">
            <Control.Template>
                <ControlTemplate>
                    <ControlTemplate.Triggers>
                        <DataTrigger Binding="{Binding ShowDeleteButton}" Value="true">
                            <DataTrigger.EnterActions>
                                <BeginStoryboard>
                                    <Storyboard>
                                        <DoubleAnimation 
                                Storyboard.TargetName="flyout"
                                Storyboard.TargetProperty="(Grid.Width)" 
                                From="0" To="120" Duration="0:0:1" AutoReverse="False"/>
                                    </Storyboard>
                                </BeginStoryboard>
                            </DataTrigger.EnterActions>
                            <DataTrigger.ExitActions>
                                <BeginStoryboard>
                                    <Storyboard>
                                        <DoubleAnimation 
                                Storyboard.TargetName="flyout"
                                Storyboard.TargetProperty="(Grid.Width)" 
                                From="120" To="0" Duration="0:0:1" AutoReverse="False"/>
                                    </Storyboard>
                                </BeginStoryboard>
                            </DataTrigger.ExitActions>
                        </DataTrigger>
                    </ControlTemplate.Triggers>
                    <Grid x:Name="flyout" Width="0">
                        <Rectangle Fill="Green"/>
                        <Label Content="I'm DELETE button" Margin="10,30,0,0" VerticalAlignment="Top"/>
                    </Grid>
                </ControlTemplate>
            </Control.Template>
        </Control>
    </Grid>
</Grid>

And the Control in Grid's second column has DataTrigger based on your ViewModel's property "ShowDeleteButton"

Since the Width of column where the Control is placed is Auto you can change the width of the Control using simple DoubleAnimation and you get desired behavior.

EDIT

Look at this if you want the flyout to be over everything else.

<Grid x:Name="LayoutRoot">
    <Grid x:Name="container" Width="120" HorizontalAlignment="Right">
            <Button x:Name="button" Content="In" Margin="0,13,7.5,0" VerticalAlignment="Top" HorizontalAlignment="Right" d:LayoutOverrides="HorizontalAlignment">
                <Button.Triggers>
                    <EventTrigger RoutedEvent="Button.Click">
                        <BeginStoryboard>
                            <Storyboard>
                                <DoubleAnimation 
                                    Storyboard.TargetName="flyout"
                                    Storyboard.TargetProperty="(Grid.Width)" 
                                    From="0" To="120" Duration="0:0:1" AutoReverse="False"/> 
                            </Storyboard>
                        </BeginStoryboard>
                    </EventTrigger>
                </Button.Triggers>
            </Button>
    </Grid>
    <Grid x:Name="flyout" Width="120" Margin="0" HorizontalAlignment="Right">
            <Rectangle Fill="Green"/>
            <Label Content="This is some label" Margin="6.038,27,1.006,0" VerticalAlignment="Top"/>
            <Button Content="Out" Margin="11.917,58,0,0" VerticalAlignment="Top" HorizontalAlignment="Left" Width="80.083">
                <Button.Triggers>
                    <EventTrigger RoutedEvent="Button.Click">
                        <BeginStoryboard>
                            <Storyboard>
                                <DoubleAnimation 
                                    Storyboard.TargetName="flyout"
                                    Storyboard.TargetProperty="(Grid.Width)" 
                                    From="120" To="0" Duration="0:0:1" AutoReverse="False"/> 
                            </Storyboard>
                        </BeginStoryboard>
                    </EventTrigger>
                </Button.Triggers>
            </Button>
        </Grid>
</Grid>

Please note that button "Out" can be clicked while it's moving. It should be probably disabled. I just did it like this because I wanted to do it simple and all in xaml. Sure you can use mahapps. Or you can just make it as fast as it is in MahApps and it's impossible to click it twice. :) I have looked at MahApps FlyOutDemo and my solution looks much simpler to me. And I don't need third party library.