UWP Xaml GridViewItem: Remove margin - xaml

Question

I want to create a grid of images without any margin between them. I tried to achieve this through a GridView. If there is an easier way, please let me know.
I found this answers on StackOverflow:
https://stackoverflow.com/a/10492464
https://stackoverflow.com/a/23817931/5739170
And ended up with this code:
<Page.Resources>
<Style x:Key="MyGridViewItemStyle" TargetType="GridViewItem">
<Setter Property="Padding" Value="0" />
<Setter Property="Margin" Value="0" />
<Setter Property="BorderThickness" Value="0" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="GridViewItem">
<GridViewItemPresenter ContentMargin="0" Padding="0" Margin="0" BorderThickness="0"/>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Page.Resources>
<Grid Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">
<StackPanel>
<GridView ItemsSource="{x:Bind FieldList}" Margin="0,50,0,0" Padding="0" BorderThickness="0" ItemContainerStyle="{StaticResource MyGridViewItemStyle}" IsItemClickEnabled="True" ItemClick="OnItemClick">
<GridView.ItemTemplate>
<DataTemplate x:DataType="data:Field">
<Image Width="20" Height="20" Margin="0" Source="{x:Bind ImagePath}"/>
</DataTemplate>
</GridView.ItemTemplate>
</GridView>
<TextBlock x:Name="text">Hallo!</TextBlock>
</StackPanel>
</Grid>
But there is still a margin left:
Screenshot
I have also tried to use negative margins but when I use them clicks aren't recognized correctly anymore.
How can I remove the margins?

Answer 1

Seems like the GridViewItem has a default MinWidth of 44px.
You can set it to 0 via your GridViewItemStyle:
<Setter Property="MinWidth" Value="0" />
EDIT: it also has a default MinHeight, you might want to set that to 0 as well.

Answer 2

The code below should work:
<GridView.ItemContainerStyle>
<Style TargetType="GridViewItem">
<Setter Property="Margin" Value="0"/>
</Style>
</GridView.ItemContainerStyle>

Answer 3

Your code is good. If you add a Grid in the DataTemplate (with a Background), you will see there is no margin between grids :
<DataTemplate x:DataType="data:Field">
<Grid Background="Red">
<Image Width="20" Height="20" Margin="0" Source="{x:Bind ImagePath}"/>
</Grid>
</DataTemplate>
Your problem is the following : you set a fixed size for Image control wich all of them is in a container, but the container doesn't have a fixed, so images are centered in the container.
I see two solutions. First is to remove the fixed size for Image control and use Strecth property to fill correctly :
<DataTemplate x:DataType="data:Field">
<Image VerticalAlignment="Stretch"
HorizontalAlignment="Stretch"
Stretch="UniformToFill"
Margin="0"
Source="{x:Bind ImagePath}"/>
</DataTemplate>
For the first solution, you must be sure of the filling behavior of the container. You can do something like :
<GridViewItemPresenter ContentMargin="0"
Padding="0"
Margin="0"
BorderThickness="0"
HorizontalAlignment="Stretch"
HorizontalContentAlignment="Stretch" />
The second solution is to set a fixed size on the container directly :
<Style x:Key="MyGridViewItemStyle"
TargetType="GridViewItem">
<Setter Property="Padding"
Value="0" />
<Setter Property="Margin"
Value="0" />
<Setter Property="BorderThickness"
Value="0" />
<Setter Property="Width"
Value="20" />
<Setter Property="Height"
Value="20" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="GridViewItem">
<GridViewItemPresenter ContentMargin="0"
Padding="0"
Margin="0"
BorderThickness="0"/>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>