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#nullable disable
using System;
using System.ComponentModel;
using System.Diagnostics;
using System.Globalization;
using System.Runtime.CompilerServices;
using System.Windows.Input;
using Microsoft.Maui.Controls.Internals;
using Microsoft.Maui.Graphics;
namespace Microsoft.Maui.Controls
{
/// <summary>
/// A button <see cref="View" /> that reacts to touch events.
/// </summary>
public partial class Button : View, IFontElement, ITextElement, IBorderElement, IButtonController, IElementConfiguration<Button>, IPaddingElement, IImageController, IViewController, IButtonElement, ICommandElement, IImageElement, IButton, ITextButton, IImageButton
{
const double DefaultSpacing = 10;
/// <summary>
/// The backing store for the <see cref="Command" /> bindable property.
/// </summary>
public static readonly BindableProperty CommandProperty = ButtonElement.CommandProperty;
/// <summary>
/// The backing store for the <see cref="CommandParameter" /> bindable property.
/// </summary>
public static readonly BindableProperty CommandParameterProperty = ButtonElement.CommandParameterProperty;
/// <summary>
/// The backing store for the <see cref="ContentLayout" /> bindable property.
/// </summary>
public static readonly BindableProperty ContentLayoutProperty = BindableProperty.Create(
nameof(ContentLayout), typeof(ButtonContentLayout), typeof(Button), new ButtonContentLayout(ButtonContentLayout.ImagePosition.Left, DefaultSpacing),
propertyChanged: (bindable, oldVal, newVal) => ((Button)bindable).InvalidateMeasureInternal(InvalidationTrigger.MeasureChanged));
/// <summary>
/// The backing store for the <see cref="Text" /> bindable property.
/// </summary>
public static readonly BindableProperty TextProperty = BindableProperty.Create(
nameof(Text), typeof(string), typeof(Button), null,
propertyChanged: (bindable, oldVal, newVal) => ((Button)bindable).InvalidateMeasureInternal(InvalidationTrigger.MeasureChanged));
/// <summary>
/// The backing store for the <see cref="TextColor" /> bindable property.
/// </summary>
public static readonly BindableProperty TextColorProperty = TextElement.TextColorProperty;
/// <summary>
/// The backing store for the <see cref="CharacterSpacing" /> bindable property.
/// </summary>
public static readonly BindableProperty CharacterSpacingProperty = TextElement.CharacterSpacingProperty;
/// <summary>
/// The backing store for the <see cref="FontFamily" /> bindable property.
/// </summary>
public static readonly BindableProperty FontFamilyProperty = FontElement.FontFamilyProperty;
/// <summary>
/// The backing store for the <see cref="FontSize" /> bindable property.
/// </summary>
public static readonly BindableProperty FontSizeProperty = FontElement.FontSizeProperty;
/// <summary>
/// The backing store for the <see cref="TextTransform" /> bindable property.
/// </summary>
public static readonly BindableProperty TextTransformProperty = TextElement.TextTransformProperty;
/// <summary>
/// The backing store for the <see cref="FontAttributes" /> bindable property.
/// </summary>
public static readonly BindableProperty FontAttributesProperty = FontElement.FontAttributesProperty;
/// <summary>
/// The backing store for the <see cref="FontAutoScalingEnabled" /> bindable property.
/// </summary>
public static readonly BindableProperty FontAutoScalingEnabledProperty = FontElement.FontAutoScalingEnabledProperty;
/// <summary>
/// The backing store for the <see cref="BorderWidth"/> bindable property.
/// </summary>
public static readonly BindableProperty BorderWidthProperty = BindableProperty.Create(nameof(BorderWidth), typeof(double), typeof(Button), -1d);
/// <summary>
/// The backing store for the <see cref="BorderColor" /> bindable property.
/// </summary>
public static readonly BindableProperty BorderColorProperty = BorderElement.BorderColorProperty;
/// <summary>
/// The backing store for the <see cref="CornerRadius"/> bindable property.
/// </summary>
public static readonly BindableProperty CornerRadiusProperty = BindableProperty.Create(nameof(CornerRadius), typeof(int), typeof(Button), defaultValue: BorderElement.DefaultCornerRadius);
/// <summary>
/// The backing store for the <see cref="ImageSource" /> bindable property.
/// </summary>
public static readonly BindableProperty ImageSourceProperty = ImageElement.ImageSourceProperty;
/// <summary>
/// The backing store for the <see cref="Padding" /> bindable property.
/// </summary>
public static readonly BindableProperty PaddingProperty = PaddingElement.PaddingProperty;
/// <summary>
/// The backing store for the <see cref="LineBreakMode"/> bindable property.
/// </summary>
public static readonly BindableProperty LineBreakModeProperty = BindableProperty.Create(
nameof(LineBreakMode), typeof(LineBreakMode), typeof(Button), LineBreakMode.NoWrap,
propertyChanged: (bindable, oldvalue, newvalue) => ((Button)bindable).InvalidateMeasureInternal(InvalidationTrigger.MeasureChanged));
/// <summary>
/// Gets or sets the padding for the button. This is a bindable property.
/// </summary>
public Thickness Padding
{
get { return (Thickness)GetValue(PaddingElement.PaddingProperty); }
set { SetValue(PaddingElement.PaddingProperty, value); }
}
Thickness IPaddingElement.PaddingDefaultValueCreator() => new Thickness(double.NaN);
/// <summary>
/// Determines how <see cref="Text"/> is shown when the length is overflowing the size of this button.
/// This is a bindable property.
/// </summary>
public LineBreakMode LineBreakMode
{
get { return (LineBreakMode)GetValue(LineBreakModeProperty); }
set { SetValue(LineBreakModeProperty, value); }
}
void IPaddingElement.OnPaddingPropertyChanged(Thickness oldValue, Thickness newValue)
{
InvalidateMeasureInternal(InvalidationTrigger.MeasureChanged);
}
internal static readonly BindablePropertyKey IsPressedPropertyKey = BindableProperty.CreateReadOnly(nameof(IsPressed), typeof(bool), typeof(Button), default(bool));
/// <summary>
/// The backing store for the <see cref="IsPressed"/> bindable property.
/// </summary>
public static readonly BindableProperty IsPressedProperty = IsPressedPropertyKey.BindableProperty;
readonly Lazy<PlatformConfigurationRegistry<Button>> _platformConfigurationRegistry;
/// <summary>
/// Gets or sets a color that describes the border stroke color of the button. This is a bindable property.
/// </summary>
/// <remarks>This property has no effect if <see cref="IBorderElement.BorderWidth" /> is set to 0. On Android this property will not have an effect unless <see cref="VisualElement.BackgroundColor" /> is set to a non-default color.</remarks>
public Color BorderColor
{
get { return (Color)GetValue(BorderElement.BorderColorProperty); }
set { SetValue(BorderElement.BorderColorProperty, value); }
}
/// <summary>
/// Gets or sets the corner radius for the button, in device-independent units. This is a bindable property.
/// </summary>
public int CornerRadius
{
get { return (int)GetValue(CornerRadiusProperty); }
set { SetValue(CornerRadiusProperty, value); }
}
/// <summary>
/// Gets or sets the width of the border, in device-independent units. This is a bindable property.
/// </summary>
/// <remarks>Set this value to a non-zero value in order to have a visible border.</remarks>
public double BorderWidth
{
get { return (double)GetValue(BorderWidthProperty); }
set { SetValue(BorderWidthProperty, value); }
}
/// <summary>
/// Gets or sets an object that controls the position of the button image and the spacing between the button's image and the button's text.
/// This is a bindable property.
/// </summary>
public ButtonContentLayout ContentLayout
{
get { return (ButtonContentLayout)GetValue(ContentLayoutProperty); }
set { SetValue(ContentLayoutProperty, value); }
}
/// <summary>
/// Gets or sets the command to invoke when the button is activated. This is a bindable property.
/// </summary>
/// <remarks>This property is used to associate a command with an instance of a button. This property is most often set in the MVVM pattern to bind callbacks back into the ViewModel. <see cref="VisualElement.IsEnabled" /> is controlled by the <see cref="Command.CanExecute(object)"/> if set.</remarks>
public ICommand Command
{
get { return (ICommand)GetValue(CommandProperty); }
set { SetValue(CommandProperty, value); }
}
/// <summary>
/// Gets or sets the parameter to pass to the <see cref="Command"/> property.
/// The default value is <see langword="null"/>. This is a bindable property.
/// </summary>
public object CommandParameter
{
get { return GetValue(CommandParameterProperty); }
set { SetValue(CommandParameterProperty, value); }
}
/// <summary>
/// Allows you to display a bitmap image on the Button. This is a bindable property.
/// </summary>
/// <remarks>For more options have a look at <see cref="ImageButton"/>.</remarks>
public ImageSource ImageSource
{
get { return (ImageSource)GetValue(ImageSourceProperty); }
set { SetValue(ImageSourceProperty, value); }
}
/// <summary>
/// Gets or sets the text displayed as the content of the button.
/// The default value is <see langword="null"/>. This is a bindable property.
/// </summary>
/// <remarks>Changing the text of a button will trigger a layout cycle.</remarks>
public string Text
{
get { return (string)GetValue(TextProperty); }
set { SetValue(TextProperty, value); }
}
/// <summary>
/// Gets or sets the <see cref="Color" /> for the text of the button. This is a bindable property.
/// </summary>
public Color TextColor
{
get { return (Color)GetValue(TextElement.TextColorProperty); }
set { SetValue(TextElement.TextColorProperty, value); }
}
/// <summary>
/// Gets or sets the spacing between each of the characters of <see cref="Text"/> when displayed on the button.
/// This is a bindable property.
/// </summary>
public double CharacterSpacing
{
get { return (double)GetValue(TextElement.CharacterSpacingProperty); }
set { SetValue(TextElement.CharacterSpacingProperty, value); }
}
/// <summary>
/// Internal method to trigger the <see cref="Clicked"/> event.
/// Should not be called manually outside of .NET MAUI.
/// </summary>
[EditorBrowsable(EditorBrowsableState.Never)]
public void SendClicked() => ButtonElement.ElementClicked(this, this);
/// <summary>
/// Gets whether or not the button is currently pressed.
/// </summary>
public bool IsPressed => (bool)GetValue(IsPressedProperty);
[EditorBrowsable(EditorBrowsableState.Never)]
void IButtonElement.SetIsPressed(bool isPressed) => SetValue(IsPressedPropertyKey, isPressed);
/// <summary>
/// Internal method to trigger the <see cref="Pressed"/> event.
/// Should not be called manually outside of .NET MAUI.
/// </summary>
[EditorBrowsable(EditorBrowsableState.Never)]
public void SendPressed() => ButtonElement.ElementPressed(this, this);
/// <summary>
/// Internal method to trigger the <see cref="Released"/> event.
/// Should not be called manually outside of .NET MAUI.
/// </summary>
[EditorBrowsable(EditorBrowsableState.Never)]
public void SendReleased() => ButtonElement.ElementReleased(this, this);
[EditorBrowsable(EditorBrowsableState.Never)]
void IButtonElement.PropagateUpClicked() => Clicked?.Invoke(this, EventArgs.Empty);
[EditorBrowsable(EditorBrowsableState.Never)]
void IButtonElement.PropagateUpPressed() => Pressed?.Invoke(this, EventArgs.Empty);
[EditorBrowsable(EditorBrowsableState.Never)]
void IButtonElement.PropagateUpReleased() => Released?.Invoke(this, EventArgs.Empty);
/// <summary>
/// Gets or sets a value that indicates whether the font for the text of this button is bold, italic, or neither.
/// This is a bindable property.
/// </summary>
public FontAttributes FontAttributes
{
get { return (FontAttributes)GetValue(FontAttributesProperty); }
set { SetValue(FontAttributesProperty, value); }
}
/// <summary>
/// Gets or sets the font family for the text of this entry. This is a bindable property.
/// </summary>
public string FontFamily
{
get { return (string)GetValue(FontFamilyProperty); }
set { SetValue(FontFamilyProperty, value); }
}
/// <summary>
/// Gets or sets the size of the font for the text of this entry. This is a bindable property.
/// </summary>
[System.ComponentModel.TypeConverter(typeof(FontSizeConverter))]
public double FontSize
{
get { return (double)GetValue(FontSizeProperty); }
set { SetValue(FontSizeProperty, value); }
}
/// <summary>
/// Determines whether or not the font of this entry should scale automatically according to the operating system settings. Default value is <see langword="true"/>.
/// This is a bindable property.
/// </summary>
/// <remarks>Typically this should always be enabled for accessibility reasons.</remarks>
public bool FontAutoScalingEnabled
{
get => (bool)GetValue(FontAutoScalingEnabledProperty);
set => SetValue(FontAutoScalingEnabledProperty, value);
}
/// <summary>
/// Applies text transformation to the <see cref="Text"/> displayed on this button.
/// This is a bindable property.
/// </summary>
public TextTransform TextTransform
{
get => (TextTransform)GetValue(TextTransformProperty);
set => SetValue(TextTransformProperty, value);
}
/// <summary>
/// Occurs when the button is clicked/tapped.
/// </summary>
public event EventHandler Clicked;
/// <summary>
/// Occurs when the button is pressed.
/// </summary>
public event EventHandler Pressed;
/// <summary>
/// Occurs when the button is released.
/// </summary>
public event EventHandler Released;
/// <summary>
/// Initializes a new instance of the <see cref="Button"/> class.
/// </summary>
public Button()
{
_platformConfigurationRegistry = new Lazy<PlatformConfigurationRegistry<Button>>(() => new PlatformConfigurationRegistry<Button>(this));
}
/// <inheritdoc/>
public IPlatformElementConfiguration<T, Button> On<T>() where T : IConfigPlatform
{
return _platformConfigurationRegistry.Value.On<T>();
}
protected internal override void ChangeVisualState()
{
if (IsEnabled && IsPressed)
{
VisualStateManager.GoToState(this, ButtonElement.PressedVisualState);
}
else
{
base.ChangeVisualState();
}
}
protected override void OnBindingContextChanged()
{
ImageSource image = ImageSource;
if (image != null)
SetInheritedBindingContext(image, BindingContext);
base.OnBindingContextChanged();
}
void IFontElement.OnFontFamilyChanged(string oldValue, string newValue) =>
HandleFontChanged();
void IFontElement.OnFontSizeChanged(double oldValue, double newValue) =>
HandleFontChanged();
double IFontElement.FontSizeDefaultValueCreator() =>
this.GetDefaultFontSize();
void IFontElement.OnFontAttributesChanged(FontAttributes oldValue, FontAttributes newValue) =>
HandleFontChanged();
void IFontElement.OnFontAutoScalingEnabledChanged(bool oldValue, bool newValue) =>
HandleFontChanged();
void HandleFontChanged()
{
Handler?.UpdateValue(nameof(ITextStyle.Font));
InvalidateMeasureInternal(InvalidationTrigger.MeasureChanged);
}
Aspect IImageElement.Aspect => Aspect.AspectFit;
ImageSource IImageElement.Source => ImageSource;
bool IImageElement.IsOpaque => false;
void IImageElement.RaiseImageSourcePropertyChanged() => OnPropertyChanged(ImageSourceProperty.PropertyName);
int IBorderElement.CornerRadiusDefaultValue => (int)CornerRadiusProperty.DefaultValue;
Color IBorderElement.BorderColorDefaultValue => (Color)BorderColorProperty.DefaultValue;
double IBorderElement.BorderWidthDefaultValue => (double)BorderWidthProperty.DefaultValue;
void ITextElement.OnTextColorPropertyChanged(Color oldValue, Color newValue)
{
}
void ITextElement.OnCharacterSpacingPropertyChanged(double oldValue, double newValue)
{
InvalidateMeasure();
}
void IBorderElement.OnBorderColorPropertyChanged(Color oldValue, Color newValue)
{
}
bool IImageController.GetLoadAsAnimation() => false;
bool IImageElement.IsLoading => false;
bool IImageElement.IsAnimationPlaying => false;
void IImageElement.OnImageSourceSourceChanged(object sender, EventArgs e) =>
ImageElement.ImageSourceSourceChanged(this, e);
void IImageController.SetIsLoading(bool isLoading)
{
}
bool IBorderElement.IsCornerRadiusSet() => IsSet(CornerRadiusProperty);
bool IBorderElement.IsBackgroundColorSet() => IsSet(BackgroundColorProperty);
bool IBorderElement.IsBackgroundSet() => IsSet(BackgroundProperty);
bool IBorderElement.IsBorderColorSet() => IsSet(BorderColorProperty);
bool IBorderElement.IsBorderWidthSet() => IsSet(BorderWidthProperty);
void ITextElement.OnTextTransformChanged(TextTransform oldValue, TextTransform newValue)
=> InvalidateMeasureInternal(InvalidationTrigger.MeasureChanged);
/// <summary>
/// Applies the <see cref="TextTransform"/> to <see cref="Text"/>.
/// </summary>
/// <remarks>For internal use by the .NET MAUI platform mostly.</remarks>
/// <param name="source">The text to transform.</param>
/// <param name="textTransform">The transform to apply to <paramref name="source"/>.</param>
/// <returns>The transformed text.</returns>
public virtual string UpdateFormsText(string source, TextTransform textTransform)
=> TextTransformUtilites.GetTransformedText(source, textTransform);
void ICommandElement.CanExecuteChanged(object sender, EventArgs e) =>
RefreshIsEnabledProperty();
protected override bool IsEnabledCore =>
base.IsEnabledCore && CommandElement.GetCanExecute(this);
bool _wasImageLoading;
protected override void OnPropertyChanged([CallerMemberName] string propertyName = null)
{
base.OnPropertyChanged(propertyName);
if (propertyName == BorderColorProperty.PropertyName)
Handler?.UpdateValue(nameof(IButtonStroke.StrokeColor));
else if (propertyName == BorderWidthProperty.PropertyName)
Handler?.UpdateValue(nameof(IButtonStroke.StrokeThickness));
else if (propertyName == ImageSourceProperty.PropertyName)
Handler?.UpdateValue(nameof(IImage.Source));
}
void IButton.Clicked()
{
(this as IButtonController).SendClicked();
}
void IButton.Pressed()
{
(this as IButtonController).SendPressed();
}
void IButton.Released()
{
(this as IButtonController).SendReleased();
}
void IImageSourcePart.UpdateIsLoading(bool isLoading)
{
if (!isLoading && _wasImageLoading)
Handler?.UpdateValue(nameof(ContentLayout));
_wasImageLoading = isLoading;
}
Font ITextStyle.Font => this.ToFont();
Aspect IImage.Aspect => Aspect.Fill;
bool IImage.IsOpaque => true;
IImageSource IImageSourcePart.Source => ImageSource;
bool IImageSourcePart.IsAnimationPlaying => false;
double IButtonStroke.StrokeThickness => (double)GetValue(BorderWidthProperty);
Color IButtonStroke.StrokeColor => (Color)GetValue(BorderColorProperty);
int IButtonStroke.CornerRadius => (int)GetValue(CornerRadiusProperty);
/// <summary>
/// Represents the layout of the button content whenever an image is shown.
/// </summary>
[DebuggerDisplay("Image Position = {Position}, Spacing = {Spacing}")]
[System.ComponentModel.TypeConverter(typeof(ButtonContentTypeConverter))]
public sealed class ButtonContentLayout
{
/// <summary>
/// Enumerates values that determine the position of the image on the button.
/// </summary>
public enum ImagePosition
{
Left,
Top,
Right,
Bottom
}
/// <summary>
/// Initializes a new instance of the this class.
/// </summary>
/// <param name="position">The position of the image.</param>
/// <param name="spacing">The spacing for the button content.</param>
public ButtonContentLayout(ImagePosition position, double spacing)
{
Position = position;
Spacing = spacing;
}
/// <summary>
/// Gets the position of the image on the button.
/// </summary>
public ImagePosition Position { get; }
/// <summary>
/// Gets the spacing for the button content.
/// </summary>
public double Spacing { get; }
/// <summary>
/// Gets the string representation of this object.
/// </summary>
/// <returns>Prints out the values of <see cref="Position"/> and <see cref="Spacing"/>.</returns>
public override string ToString() => $"Image Position = {Position}, Spacing = {Spacing}";
}
/// <summary>
/// A converter to convert a string to a <see cref="ButtonContentLayout"/> object.
/// </summary>
public sealed class ButtonContentTypeConverter : TypeConverter
{
public override bool CanConvertFrom(ITypeDescriptorContext context, Type sourceType)
=> sourceType == typeof(string);
public override bool CanConvertTo(ITypeDescriptorContext context, Type destinationType)
=> false;
public override object ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, object value)
{
// IMPORTANT! Update ButtonContentDesignTypeConverter.IsValid if making changes here
var strValue = value?.ToString();
if (strValue == null)
throw new InvalidOperationException($"Cannot convert null into {typeof(ButtonContentLayout)}");
string[] parts = strValue.Split(new[] { ',' }, StringSplitOptions.RemoveEmptyEntries);
if (parts.Length != 1 && parts.Length != 2)
throw new InvalidOperationException($"Cannot convert \"{strValue}\" into {typeof(ButtonContentLayout)}");
double spacing = DefaultSpacing;
var position = ButtonContentLayout.ImagePosition.Left;
var spacingFirst = char.IsDigit(parts[0][0]);
int positionIndex = spacingFirst ? (parts.Length == 2 ? 1 : -1) : 0;
int spacingIndex = spacingFirst ? 0 : (parts.Length == 2 ? 1 : -1);
if (spacingIndex > -1)
spacing = double.Parse(parts[spacingIndex]);
if (positionIndex > -1)
position = (ButtonContentLayout.ImagePosition)Enum.Parse(typeof(ButtonContentLayout.ImagePosition), parts[positionIndex], true);
return new ButtonContentLayout(position, spacing);
}
public override object ConvertTo(ITypeDescriptorContext context, CultureInfo culture, object value, Type destinationType)
=> throw new NotSupportedException();
}
}
}
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