forked from joejulian/gio
Egon Elbre
21ef492cc9
color.RGBA has two problems with regards to using it. First the color values need to be premultiplied, whereas most APIs have non-premultiplied values. This is mainly to preserve color components with low alpha values. Second there are two ways to premultiply with sRGB. One is to premultiply after sRGB conversion, the other is before. This makes using the API more confusing. Using color.NRGBA in sRGB makes it align with CSS.e Signed-off-by: Egon Elbre <egonelbre@gmail.com>
60 lines
2.0 KiB
Go
60 lines
2.0 KiB
Go
// SPDX-License-Identifier: Unlicense OR MIT
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// Package material implements the Material design.
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//
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// To maximize reusability and visual flexibility, user interface controls are
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// split into two parts: the stateful widget and the stateless drawing of it.
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//
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// For example, widget.Clickable encapsulates the state and event
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// handling of all clickable areas, while the Theme is responsible to
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// draw a specific area, for example a button.
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//
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// This snippet defines a button that prints a message when clicked:
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//
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// var gtx layout.Context
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// button := new(widget.Clickable)
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//
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// for button.Clicked(gtx) {
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// fmt.Println("Clicked!")
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// }
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//
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// Use a Theme to draw the button:
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//
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// theme := material.NewTheme(...)
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//
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// material.Button(theme, "Click me!").Layout(gtx, button)
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//
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// Customization
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//
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// Quite often, a program needs to customize the theme-provided defaults. Several
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// options are available, depending on the nature of the change.
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//
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// Mandatory parameters: Some parameters are not part of the widget state but
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// have no obvious default. In the program above, the button text is a
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// parameter to the Theme.Button method.
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//
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// Theme-global parameters: For changing the look of all widgets drawn with a
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// particular theme, adjust the `Theme` fields:
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//
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// theme.Color.Primary = color.NRGBA{...}
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//
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// Widget-local parameters: For changing the look of a particular widget,
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// adjust the widget specific theme object:
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//
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// btn := material.Button(theme, "Click me!")
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// btn.Font.Style = text.Italic
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// btn.Layout(gtx, button)
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//
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// Widget variants: A widget can have several distinct representations even
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// though the underlying state is the same. A widget.Clickable can be drawn as a
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// round icon button:
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//
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// icon := material.NewIcon(...)
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//
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// material.IconButton(theme, icon).Layout(gtx, button)
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//
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// Specialized widgets: Theme both define a generic Label method
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// that takes a text size, and specialized methods for standard text
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// sizes such as Theme.H1 and Theme.Body2.
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package material
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