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Grid extensions

The Grid extensions provide a series of extension methods that support configuring a Grid.

Defining Rows + Columns

To define rows and columns for a Grid, CommunityToolkit.Maui.Markup provides two helper methods:

  • Columns.Define
  • Rows.Define

To leverage these helper methods, we first add the following using static directive to the top of our class:

using static CommunityToolkit.Maui.Markup.GridRowsColumns;

After adding the above using static directive, we can then define our Row + Column sizes using the following values to set the GridLength:

Microsoft.Maui.GridLength XAML CommunityToolkit.Maui.Markup.GridRowsColumns
GridLength.Auto Auto Auto
GridLength.Star * Star
new GridLength(2, GridLength.Star) 2* Stars(2)
new GridLength(20, GridLength.Absolute) 20 20

Putting it all together, we can now define a Grid's Rows + Columns:

new Grid
{
    ColumnDefinitions = Columns.Define(30, Star, Stars(2)),
    RowDefinitions = Rows.Define(Auto, Star),   
};

Example

The following example demonstrates how to create a Grid with 2 Rows:

  • Row 0 Size: GridLength.Auto
  • Row 1 Size: GridLength.Star

The following example demonstrates how to create a Grid with 3 Columns:

  • Column 0 Size: new GridLength(30, GridLength.Absolute)
  • Column 1 Size: GridLength.Star
  • Column 2 Size: new GridLength(GridLength.Star, 2):
// Add this using static to enable Columns.Define and Rows.Define 
using static CommunityToolkit.Maui.Markup.GridRowsColumns;

// ...

new Grid
{
    ColumnDefinitions = Columns.Define(30, Star, Stars(2)),
    RowDefinitions = Rows.Define(Auto, Star),

    Children = 
    {
        new Label()
            .Text("This Label is in Row 0 Column 0")
            .Row(0).Column(0)

        new Label()
            .Text("This Label is in Row 0 Column 1")
            .Row(0).Column(1)

        new Label()
            .Text("This Label is in Row 0 Column 2")
            .Row(1).Column(2)

        new Label()
            .Text("This Label is in Row 1 Column 0")
            .Row(1).Column(0)

        new Label()
            .Text("This Label is in Row 1 Column 1")
            .Row(1).Column(1)

        new Label()
            .Text("This Label is in Row 1 Column 2")
            .Row(1).Column(2)
    }
}

Defining Rows + Columns Using Enums

We can also define and name our Rows and Columns by creating a custom Enum. Using an Enum allows us to define a name for each row and column making it easier to place our controls in the Grid.

Example

The following example demonstrates how to define rows + columns for a Grid using two Enums.

To leverage these helper methods, we first add the following using static directive:

using static CommunityToolkit.Maui.Markup.GridRowsColumns;

We then define the names of our Rows and Columns by creating a custom Enum for each:

enum Row { Username, Password, Submit }

enum Column { Description, UserInput }

We then then populate our Grid using these Enums to define our rows + columns and to assign each control to a row + column accordingly:

using static CommunityToolkit.Maui.Markup.GridRowsColumns;

class LoginPage : ContentPage
{
    public LoginPage()
    {
        Content = new Grid
        {
            RowDefinitions = Rows.Define(
                (Row.Username, 30),
                (Row.Password, 30),
                (Row.Submit, Star)),
    
            ColumnDefinitions = Columns.Define(
                (Column.Description, Star),
                (Column.UserInput, Star)),
    
            Children = 
            {
                new Label()
                    .Text("Username")
                    .Row(Row.Username).Column(Column.Description),
    
                new Entry()
                    .Placeholder("Username")
                    .Row(Row.Username).Column(Column.UserInput),
    
                new Label()
                    .Text("Password")
                    .Row(Row.Password).Column(Column.Description),
    
                new Entry { IsPassword = true }
                    .Placeholder("Password")
                    .Row(Row.Password).Column(Column.UserInput),
    
                new Button()
                    .Text("Submit")
                    .Row(Row.Password).RowSpan(All<Column>())
            }
        }
    }

    enum Row { Username, Password, Submit }

    enum Column { Description, UserInput }
}

Row

The Row method sets the Grid.RowProperty and Grid.RowSpanProperty on a BindableObject.

The following example sets the Grid.RowProperty of a Button to 0 and its Grid.RowSpanProperty to 2, then sets the Grid.RowProperty of a Label to 1:

new Grid
{
    Children = 
    {
        new Button()
            .Text("This Button is in Row 0 and spans 2 Columns")
            .Row(0, 2),

        new Label()
            .Text("This Label is in Row 1 and does not span multiple columns")
            .Row(1)
    }
};

Column

The Column method sets the Grid.ColumnProperty and Grid.ColumnSpanProperty on a BindableObject.

The following example sets the Grid.ColumnProperty of a Button to 0 and its Grid.ColumnSpanProperty to 2, then sets the Grid.ColumnProperty of a Label to 1:

new Grid
{
    Children = 
    {
        new Button()
            .Text("This Button is in Row 0 and spans 2 Columns")
            .Column(0, 2),

        new Label()
            .Text("This Label is in Row 1 and does not span multiple columns")
            .Column(1)
    }
};

RowSpan

The RowSpan method allows us to define how many Grid Rows a control will span across. I.e. If our Grid has 3 Rows, .RowSpan(3) will ensure the control spans across all 3 Columns.

Here's an example of a Button that spans vertically across 3 Rows:

new Button()
    .Text("This Button Spans Across 3 Grid Rows")
    .RowSpan(3)

All<TEnum>

When defining our Rows using an Enum, we can use All<TEnum>() to ensure our control spans vertically across every row:

enum Row { Username, Password, Submit }

// ...
new Button()
    .Text("This Button Spans Vertically Across Every Row Defined in our Enum")
    .RowSpan(All<Row>());

ColumnSpan

The ColumnSpan method allows us to define how many Grid Columns a control will span across. I.e. If our Grid has 3 Columns, .ColumnSpan(3) will ensure the control spans across all 3 Columns.

Here's an example of a Button that spans horizontally across 3 Columns:

new Button()
    .Text("This Button Spans Across 3 Grid Columns")
    .ColumnSpan(3)

All<TEnum>

When defining our Rows using an Enum, we can use All<TEnum>() to ensure our control spans horizontally across every column:

enum Column { Description, UserInput }

// ...
new Button()
    .Text("This Button Spans Vertically Across Every Row Defined in our Enum")
    .ColumnSpan(All<Column>());

Last<TEnum>

When defining our rows and columns using an Enum, we can ensure a control is added to the last Row or the last Column by using .Last<TEnum>().

This example demonstrates how to add a Button to the final row and column in a Grid

enum Row { Username, Password, Submit }
enum Column { Description, UserInput }

// ...
new Button()
    .Text("This Button Spans Vertically Across Every Row Defined in our Enum")
    .Row(Last<Row>()).Column(Last<Column>());