X.BindableProperty.Generator 0.3.0

Xamarin.BindableProperty.Generator

Source generator that automatically transforms fields into BindableProperties that can be used in Xamarin.<br /> Are you looking for the MAUI project? check this link

Installation

First, install NuGet. Then, install X.BindableProperty.Generator from the package manager console:

PM> Install-Package X.BindableProperty.Generator

Usage - Simple implementation

Just decorate field with the Bindable attribute.

    using Xamarin.BindableProperty.Generator.Core;

    public partial class CustomEntry : ContentView
    {
        [AutoBindable]
        private string _placeholder;
    }

the prevoius code will generate this:

    public partial class CustomEntry
    {
        public static readonly Xamarin.Forms.BindableProperty PlaceholderProperty =
                                    Xamarin.Forms.BindableProperty.Create(
                                                    nameof(Placeholder),
                                                    typeof(string),
                                                    typeof(CustomEntry),
                                                    default(string));

        public string Placeholder
        {
            get => (string)GetValue(PlaceholderProperty);
            set => SetValue(PlaceholderProperty, value);
        }
    }

Usage - Custom property name

Just decorate field with the Bindable attribute.

    using Xamarin.BindableProperty.Generator.Core;

    public partial class CustomEntry : ContentView
    {
        [AutoBindable(PropertyName = "Text")]
        private string _t;
    }

the prevoius code will generate this:

    public partial class CustomEntry
    {
        public static readonly Xamarin.Forms.BindableProperty TextProperty =
                                    Xamarin.Forms.BindableProperty.Create(
                                                    nameof(Text),
                                                    typeof(string),
                                                    typeof(CustomEntry),
                                                    default(string));

        public string Text
        {
            get => (string)GetValue(TextProperty);
            set => SetValue(TextProperty, value);
        }
    }

Usage - OnChanged method

Example 1 - No Parameters

Just decorate field with the Bindable attribute.

    using Xamarin.BindableProperty.Generator.Core;

    public partial class HeaderControl : ContentView
    {
        [AutoBindable(OnChanged = nameof(UpdateDisplayName))]
        private string _firstName;

        private void UpdateDisplayName()
        { 
            // Do stuff here
        }
    }

the prevoius code will generate this:

    public partial class HeaderControl
    {
        public static readonly Xamarin.Forms.BindableProperty FirstNameProperty =
                                    Xamarin.Forms.BindableProperty.Create(
                                                    nameof(FirstName),
                                                    typeof(string),
                                                    typeof(HeaderControl),
                                                    defaultValue: default(string),
                                                    propertyChanged: __UpdateDisplayName);

        public string FirstName
        {
            get => (string)GetValue(FirstNameProperty);
            set => SetValue(FirstNameProperty, value);
        }

        private static void __UpdateDisplayName(Xamarin.Forms.BindableObject bindable, object oldValue, object newValue)
        {
            var ctrl = (HeaderControl)bindable;
            ctrl.UpdateDisplayName();
        }
    }

Example 2 - One Parameter

Just decorate field with the Bindable attribute. The 'UpdateDisplayName' method must have only one parameter (must match the type of the field)

    using Xamarin.BindableProperty.Generator.Core;

    public partial class HeaderControl : ContentView
    {
        [AutoBindable(OnChanged = nameof(UpdateDisplayName))]
        private string _firstName;

        private void UpdateDisplayName(string newValue)
        { 
            // Do stuff here
        }
    }

the prevoius code will generate this:

    public partial class HeaderControl
    {
        public static readonly Xamarin.Forms.BindableProperty FirstNameProperty =
                                    Xamarin.Forms.BindableProperty.Create(
                                                    nameof(FirstName),
                                                    typeof(string),
                                                    typeof(HeaderControl),
                                                    defaultValue: default(string),
                                                    propertyChanged: __UpdateDisplayName);

        public string FirstName
        {
            get => (string)GetValue(FirstNameProperty);
            set => SetValue(FirstNameProperty, value);
        }

        private static void __UpdateDisplayName(Xamarin.Forms.BindableObject bindable, object oldValue, object newValue)
        {
            var ctrl = (HeaderControl)bindable;
            ctrl.UpdateDisplayName((string)newValue);
        }
    }

Example 3 - Two Parameters

Just decorate field with the Bindable attribute. The 'UpdateDisplayName' method must have two parameters (must match the type of the field)

    using Xamarin.BindableProperty.Generator.Core;

    public partial class HeaderControl : ContentView
    {
        [AutoBindable(OnChanged = nameof(UpdateDisplayName))]
        private string _firstName;

        private void UpdateDisplayName(string oldValue, string newValue)
        { 
            // Do stuff here
        }
    }

the prevoius code will generate this:

    public partial class HeaderControl
    {
        public static readonly Xamarin.Forms.BindableProperty FirstNameProperty =
                                    Xamarin.Forms.BindableProperty.Create(
                                                    nameof(FirstName),
                                                    typeof(string),
                                                    typeof(HeaderControl),
                                                    defaultValue: default(string),
                                                    propertyChanged: __UpdateDisplayName);

        public string FirstName
        {
            get => (string)GetValue(FirstNameProperty);
            set => SetValue(FirstNameProperty, value);
        }

        private static void __UpdateDisplayName(Xamarin.Forms.BindableObject bindable, object oldValue, object newValue)
        {
            var ctrl = (HeaderControl)bindable;
            ctrl.UpdateDisplayName((string)oldValue, (string)newValue);
        }
    }

Usage - Set default value

Example 1 - DateTime

Just decorate field with the Bindable attribute and add the "text/value" that you want to use as default value.

    using Xamarin.BindableProperty.Generator.Core;

    public partial class HeaderControl : ContentView
    {
        [AutoBindable(DefaultValue = "System.DateTime.Now")]
        private DateTime _birthDate;
    }

the prevoius code will generate this:

    public partial class HeaderControl
    {
        public static readonly Xamarin.Forms.BindableProperty BirthDateProperty =
                                    Xamarin.Forms.BindableProperty.Create(
                                                    nameof(BirthDate),
                                                    typeof(System.DateTime),
                                                    typeof(HeaderControl),
                                                    defaultValue: System.DateTime.Now);

        public System.DateTime BirthDate
        {
            get => (System.DateTime)GetValue(BirthDateProperty);
            set => SetValue(BirthDateProperty, value);
        }
    }

Example 2 - String

Just decorate field with the Bindable attribute and add the "text/value" that you want to use as default value.

    using Xamarin.BindableProperty.Generator.Core;

    public partial class HeaderControl : ContentView
    {
        [AutoBindable(DefaultValue = "USA")]
        private string _country;
    }

the prevoius code will generate this:

    public partial class HeaderControl
    {
        public static readonly Xamarin.Forms.BindableProperty CountryProperty =
                                    Xamarin.Forms.BindableProperty.Create(
                                                    nameof(Country),
                                                    typeof(string),
                                                    typeof(HeaderControl),
                                                    defaultValue: "USA");

        public string Country
        {
            get => (string)GetValue(CountryProperty);
            set => SetValue(CountryProperty, value);
        }
    }

Usage - Set default BindingMode

Just decorate field with the Bindable attribute and add the "BindingMode" that you want to use as default value.

    using Xamarin.BindableProperty.Generator.Core;

    public partial class HeaderControl : ContentView
    {
        [AutoBindable(DefaultBindingMode = nameof(BindingMode.TwoWay))]
        private string _firstName;
    }

the prevoius code will generate this:

    public partial class HeaderControl
    {
        public static readonly Xamarin.Forms.BindableProperty FirstNameProperty =
                                    Xamarin.Forms.BindableProperty.Create(
                                                    nameof(FirstName),
                                                    typeof(string),
                                                    typeof(HeaderControl),
                                                    defaultValue: default(string),
                                                    defaultBindingMode: Xamarin.Forms.BindingMode.TwoWay);

        public string FirstName
        {
            get => (string)GetValue(FirstNameProperty);
            set => SetValue(FirstNameProperty, value);
        }
    }

Usage - Hide existing BindableProperties

Just decorate field with the Bindable attribute and set "HidesUnderlyingProperty = true".

    using Xamarin.BindableProperty.Generator.Core;

    public partial class HeaderControl : ContentView
    {
        [AutoBindable(HidesUnderlyingProperty = true)]
        private readonly Color _backgroundColor;
    }

the prevoius code will generate this:

    public partial class HeaderControl
    {
        public static new readonly Xamarin.Forms.BindableProperty BackgroundColorProperty =
                                        Xamarin.Forms.BindableProperty.Create(
                                                        nameof(BackgroundColor),
                                                        typeof(Xamarin.Forms.Color),
                                                        typeof(HeaderControl));

        public new Xamarin.Forms.Color BackgroundColor
        {
            get => (Xamarin.Forms.Color)GetValue(BackgroundColorProperty);
            set => SetValue(BackgroundColorProperty, value);
        }
    }

Project status

• ✅ Simple implementation - Done
• ✅ Custom property name - Done
• ✅ Custom Parameters - Done
• ✅ OnChanged method - Done
• ✅ OnChanged method overloading - Done

Extra info

This repo is using part of the code of CodeWriter to generate the CSharp files, thanks to the author.