Textbox alignment inside Groupbox (WPF) - wpf

Question

I'm having trouble with placing a textbox inside a groupbox (which is inside a grid). Since groupbox can contain only one children I created a grid to place labels and textboxes. The problem is - the textboxes created inside the groupboxes are left aligned according to the 2nd column of the grid inside the groupbox. I need the textboxes to be aligned left in the 2nd column of the main grid.
My xaml code
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
</Grid.RowDefinitions>
<GroupBox Grid.Row="0" Grid.Column="0" Grid.ColumnSpan="2">
<GroupBox.Header>
<Label Content="Header"></Label>
</GroupBox.Header>
<Grid Grid.Row="0" Column="0">
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
</Grid.ColumnDefinitions>
<Label Grid.Column="0" Content="Label1:"/>
<TextBox Grid.Column="1" />
<Label Grid.Column="0" Grid.Row="1" Content="Label2:"/>
<TextBox Grid.Row="1" Grid.Column="1"/>
</Grid>
</GroupBox>
</Grid>
Output for this code
You could see the textboxes in the column 1 of the main grid. If you look at the image, there is a radio button below that row which is in the second column. I need the textboxes to be aligned with that radiobutton I need them in the second column.

Answer 1

Width="Auto" means the Column will automatically take a width.
You need to use something like this instead;
`<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>`
Have a look at this ColumnWidths for further explanation if needed.
To move the TextBoxes to the next Column in the main Grid, you need to remove them from the GroupBox and add them to the main Grid instead. You haven't posted the whole XAML so it's difficult to advise further.

Answer 2

if there are going to be only two columns in your grid then just below column definitions for your inner Grid:
<Grid.ColumnDefinitions>
<ColumnDefinition Width="50*"/>
<ColumnDefinition Width="50*" />
</Grid.ColumnDefinitions>
As you want to align with the radio buttons that must be in second column of main grid then for ColSpan=2 this will perfectly.
When Width is set to Auto for a ColumnDefinition of a Grid it
will take the width of element defined in the Column , So that's
the first thing you should remove a you are not using fixed Width
for TextBoxes.