Style<T>

Cikk
01/18/2023

Style<T> provides a series of fluent extension methods that support configuring Microsoft.Maui.Controls.Style.

Constructors

Style<T> provides the following constructors:

public Style(BindableProperty property, object value);
public Style(params (BindableProperty Property, object Value)[] setters);

These constructors can be used to initialize Style<T> and assign it to a Microsoft.Maui.Controls.Style for a single setter, like so:

new Label
{
    Style = new Style<Entry>(Entry.TextColorProperty, Colors.Red)
}

These constructors can also be used to initialize Style<T> and assign it to a Microsoft.Maui.Controls.Style for multiple setter using types, like so:

new Label
{
    Style = new Style<Entry>(
            (Entry.TextColorProperty, Colors.Red),
            (Entry.BackgroundColorProperty, Colors.White),
            (Entry.FontAttributesProperty, FontAttributes.Bold))
}

Properties

Style<T> contains one property, MauiStyle.

This property leverages Microsoft.Maui.Controls.Style and is assigned upon initialization.

The styles added to, and implemented in, Style<T> are stored in the MauiStyle property.

public Microsoft.Maui.Controls.Style MauiStyle { get; }

Methods

Style<T> offers a fluent extension methods to Add additional styles, to set ApplyToDerivedTypes, to set BasedOn, and to set CanCascade.

Add

Style<T> offers multiple ways to add to an existing style:

public Style<T> Add(BindableProperty property, object value);
public Style<T> AddAppThemeBinding(BindableProperty property, object light, object dark);
public Style<T> Add(params (BindableProperty Property, object Value)[] setters);
public Style<T> AddAppThemeBindings(params (BindableProperty Property, object Light, object Dark)[] setters);
public Style<T> Add(params Behavior[] behaviors);
public Style<T> Add(params TriggerBase[] triggers);

The Add methods can be used like so:

new Label
{
    Style = new Style<Label>()
                .AddAppThemeBinding(Label.TextColorProperty, Colors.Red, Colors.Orange)
                .Add((Label.BackgroundColorProperty, Colors.White), (Label.FontAttributesProperty, FontAttributes.Bold))
                .Add(new NumericValidationBehavior())
                .Add(new EventTrigger { Event = nameof(Label.Focused) });
}

For more information on the use of AddAppThemeBinding refer to the Theming documentation.

ApplyToDerivedTypes

The fluent extension method, ApplyToDerivedTypes(bool value), sets the value of the AppleToDerivedTypes property:

public Style<T> ApplyToDerivedTypes(bool value);

It can be used like so:

new Label
{
    Style = new Style<Label>(Label.TextColorProperty, Colors.Red)
                .ApplyToDerivedTypes(true);
}

BasedOn

The fluent extension method, BasedOn(Style value), sets the value of the BasedOn property:

public Style<T> BasedOn(Style value);

It can be used like so to base the current style on an existing style:

new VerticalStackLayout
{
    Children = 
    {
        new Label
        {
            Style = new Style<Label>(Label.TextColorProperty, Colors.Red)
        }.Assign(out Label redTextLabel),

        new Label
        {
          Style = new Style<Label>().BasedOn(redTextLabel.Style);
        }
    }
};

CanCascade

The fluent extension method, CanCascade(bool value), sets the value of the CanCascade property:

public Style<T> CanCascade(bool value);