This library helps you to reduce writing boilerplate code when creating your custom UI components.
BindableProp - Basic Usage
Let say you want to create your own text input. Here's how it looks:
namespace MyMauiApp.Controls;
public class TextInput : ContentView
{
public string Text
{
get => (string)GetValue(TextInput.TextProperty);
set => SetValue(TextInput.TextProperty, value);
}
public static readonly BindableProperty TextProperty = BindableProperty.Create(
nameof(Text), typeof(string), typeof(TextInput), string.Empty
);
public string PlaceHolder
{
get => (string)GetValue(TextInput.PlaceHolderProperty);
set => SetValue(TextInput.PlaceHolderProperty, value);
}
public static readonly BindableProperty PlaceHolderProperty = BindableProperty.Create(
nameof(PlaceHolder), typeof(string), typeof(TextInput), string.Empty
);
public TextInput()
{
// Implement your logic
}
}
With BindableProps, your code will become like this:
using BindableProps;
namespace MyMauiApp.Controls;
// Notice: Your class must be partial class
public partial class TextInput : ContentView
{
[BindableProp]
string text;
[BindableProp]
string placeHolder;
public TextInput()
{
// This piece is same as above
}
}
The real magic happens at Solution Explorer > Dependencies > Analyzers > BindablePropsSG
What you would see in TextInput.g.cs is the boilerplate code which you had to write. I'll write them for you!
using BindableProps;
namespace MyMauiApp.Controls
{
public partial class TextInput
{
public static readonly BindableProperty TextProperty = BindableProperty.Create(
nameof(Text),
typeof(string),
typeof(TextInput),
default,
(BindingMode)0,
null,
(bindable, oldValue, newValue) =>
((TextInput)bindable).Text = (string)newValue,
null,
null,
null
);
public string Text
{
get => text;
set
{
OnPropertyChanging(nameof(Text));
text = value;
SetValue(TextInput.TextProperty, text);
OnPropertyChanged(nameof(Text));
}
}
public static readonly BindableProperty PlaceHolderProperty = BindableProperty.Create(
nameof(PlaceHolder),
typeof(string),
typeof(TextInput),
default,
(BindingMode)0,
null,
(bindable, oldValue, newValue) =>
((TextInput)bindable).PlaceHolder = (string)newValue,
null,
null,
null
);
public string PlaceHolder
{
get => placeHolder;
set
{
OnPropertyChanging(nameof(PlaceHolder));
placeHolder = value;
SetValue(TextInput.PlaceHolderProperty, placeHolder);
OnPropertyChanged(nameof(PlaceHolder));
}
}
}
}
The above example is the minimal amount of code to work. Here is the complete features:
public partial class TextInput : ContentView
{
// Create prop with a few settings
[BindableProp(DefaultBindingMode = ((int)BindingMode.TwoWay))]
string text = "From every time";
// Full setting
[BindableProp(
DefaultBindingMode = ((int)BindingMode.OneWay),
ValidateValueDelegate = nameof(ValidateValue),
PropertyChangedDelegate = nameof(PropertyChangedDelegate),
PropertyChangingDelegate = nameof(PropertyChangingDelegate),
CoerceValueDelegate = nameof(CoerceValueDelegate),
CreateDefaultValueDelegate = nameof(CreateDefaultValueDelegate)
)]
string placeHolder = "Always!";
static bool ValidateValue(BindableObject bindable, object value)
{
return true;
}
static void PropertyChangedDelegate(BindableObject bindable, object oldValue, object newValue)
{
// Do something
}
static void PropertyChangingDelegate(BindableObject bindable, object oldValue, object newValue)
{
// Do something
}
static object CoerceValueDelegate(BindableObject bindable, object value)
{
// Do something
return 0;
}
static object CreateDefaultValueDelegate(BindableObject bindable)
{
// Do something
return string.Empty;
}
}
And the corresponding result would like:
public partial class TextInput
{
public static readonly BindableProperty TextProperty = BindableProperty.Create(
nameof(Text),
typeof(string),
typeof(TextInput),
"From every time",
(BindingMode)((int)BindingMode.TwoWay),
null,
(bindable, oldValue, newValue) =>
((TextInput)bindable).Text = (string)newValue,
null,
null,
null
);
public string Text
{
get => text;
set
{
OnPropertyChanging(nameof(Text));
text = value;
SetValue(TextInput.TextProperty, text);
OnPropertyChanged(nameof(Text));
}
}
public static readonly BindableProperty PlaceHolderProperty = BindableProperty.Create(
nameof(PlaceHolder),
typeof(string),
typeof(TextInput),
"Always!",
(BindingMode)((int)BindingMode.OneWay),
ValidateValue,
PropertyChangedDelegate,
PropertyChangingDelegate,
CoerceValueDelegate,
CreateDefaultValueDelegate
);
public string PlaceHolder
{
get => placeHolder;
set
{
OnPropertyChanging(nameof(PlaceHolder));
placeHolder = value;
SetValue(TextInput.PlaceHolderProperty, placeHolder);
OnPropertyChanged(nameof(PlaceHolder));
}
}
}
Finally, you can use your component in other page/view like a normal component. For example, at MainPage.xaml:
If you just need the default setting for all of your props, try this:
[AllBindableProps]
public partial class TextInput : ContentView
{
// Default field
string text;
// Support field with a default value
string placeHolder = "Do you trust me?";
// This field will be handled by BindableProp
[BindableProp(
DefaultBindingMode = (int)BindingMode.TwoWay,
ValidateValueDelegate = nameof(ValidateValue)
)]
string message = "With every cell in my body!";
[IgnoredProp]
bool isBusy; // Don't touch!
// If you have existing props, we don't touch them
public static readonly BindableProperty ErrorProperty = BindableProperty.Create(
nameof(Error),
typeof(string),
typeof(TextInput),
"Things just get out of hand",
(BindingMode)(int)BindingMode.OneWayToSource
);
// Also not touch this prop
public string Error
{
get => (string)GetValue(TextInput.ErrorProperty);
set
{
SetValue(TextInput.ErrorProperty, value);
}
}
static bool ValidateValue(BindableObject bindable, object value)
{
return true;
}
public TextInput()
{
InitializeComponent();
}
}
And the result is:
namespace WibuTube.Controls
{
public partial class TextInput
{
public static readonly BindableProperty TextProperty = BindableProperty.Create(
nameof(Text),
typeof(string),
typeof(TextInput),
default,
propertyChanged: (bindable, oldValue, newValue) =>
((TextInput)bindable).Text = (string)newValue
);
public string Text
{
get => text;
set
{
OnPropertyChanging(nameof(Text));
text = value;
SetValue(TextInput.TextProperty, text);
OnPropertyChanged(nameof(Text));
}
}
public static readonly BindableProperty PlaceHolderProperty = BindableProperty.Create(
nameof(PlaceHolder),
typeof(string),
typeof(TextInput),
"Do you trust me?",
propertyChanged: (bindable, oldValue, newValue) =>
((TextInput)bindable).PlaceHolder = (string)newValue
);
public string PlaceHolder
{
get => placeHolder;
set
{
OnPropertyChanging(nameof(PlaceHolder));
placeHolder = value;
SetValue(TextInput.PlaceHolderProperty, placeHolder);
OnPropertyChanged(nameof(PlaceHolder));
}
}
}
}
Roadmap
The BindableProp along is just not enough for covering all use-cases of BindableProperty. Planning features:
Attribute
Equivalent/Description
Status
BindableAttachedProp
BindableProperty.CreateAttached
BindableAttachedReadOnlyProp
BindablePropertyKey.CreateAttachedReadOnly
BindableReadOnlyProp
BindablePropertyKey.CreateReadOnly
AllBindableProps
Put this to your class, Default BindableProp to all field members
