What does exactly the star in size terms in WPF mean?
In a WPF Grid, Width="*"
or Height="*"
means proportional sizing.
For example: to give 30% to column 1 and 70% to column 2 -
<ColumnDefinition Width="3*" />
<ColumnDefinition Width="7*" />
And likewise for rows -
<RowDefinition Height="3*" />
<RowDefinition Height="7*" />
The numbers do not have to be integers.
If the Width for RowDefinition (Height for ColumnDefinition) is omitted, 1* is implied.
In this example, column 1 is 1.5 times wider than column 2 -
<ColumnDefinition Width="1.5*" />
<ColumnDefinition />
You can mix auto-fit and fixed widths with * (proportional) widths; in that case the * columns are apportioned to the remainder after the auto-fit and fixed widths have been calculated -
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto" /> <!-- Auto-fit to content, 'Hi' -->
<ColumnDefinition Width="50.5" /> <!-- Fixed width: 50.5 device units) -->
<ColumnDefinition Width="69*" /> <!-- Take 69% of remainder -->
<ColumnDefinition Width="31*"/> <!-- Take 31% of remainder -->
</Grid.ColumnDefinitions>
<TextBlock Text="Hi" Grid.Column="0" />