ColorUtil class abstract final

Color conversion utilities: hex <-> RGB <-> ARGB, palette helpers.

Uses plain Dart int to represent colors (0xAARRGGBB), so it works in pure Dart projects without Flutter dependency.

Example:

ColorUtil.hexToInt('#FF5733');                // 0xFFFF5733
ColorUtil.intToRgb(0xFFFF5733);              // [255, 87, 51]
ColorUtil.rgbToInt(255, 87, 51);             // 0xFFFF5733
ColorUtil.intToHex(0xFFFF5733);              // #FF5733
ColorUtil.isDark(0xFF000000);                // true

Properties

hashCode → int
The hash code for this object.
no setterinherited
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited

Methods

noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
toString() → String
A string representation of this object.
inherited

Operators

operator ==(Object other) → bool
The equality operator.
inherited

Static Methods

alpha(int color) → int
Alpha channel 0, 255.
argb(int color) → List<int>
Returns [a, r, g, b] each in 0, 255.
argbToInt(int a, int r, int g, int b) → int
Build ARGB int from channels (all 0, 255).
blue(int color) → int
Blue channel 0, 255.
fromHex(String hex, {int fallback = 0xFF000000}) → int
Same as tryParse but returns fallback instead of -1 on failure.
green(int color) → int
Green channel 0, 255.
invert(int color) → int
Invert the RGB channels (alpha preserved).
isDark(int color) → bool
Whether the color is "dark" (luminance < 0.5).
isLight(int color) → bool
Whether the color is "light" (luminance >= 0.5).
lerp(int a, int b, double t) → int
Linearly interpolate between a and b by factor t (0..1).
luminance(int color) → double
Relative luminance (per WCAG formula). Range 0, 1.
red(int color) → int
Red channel 0, 255.
rgb(int color) → List<int>
Returns [r, g, b] (no alpha).
rgbToInt(int r, int g, int b) → int
Build RGB int with full opacity alpha.
toHex(int color) → String
Convert color int to #RRGGBB format (alpha stripped).
toHexArgb(int color) → String
Convert color int to #AARRGGBB format.
tryParse(String hex) → int
Parse a hex color string to int. Accepts #RGB, #RRGGBB, #AARRGGBB and plain RRGGBB / AARRGGBB without leading #. Returns -1 if invalid.
withAlpha(int color, int a) → int
Returns a copy of color with alpha overridden.
withBlue(int color, int b) → int
Returns a copy of color with blue overridden.
withGreen(int color, int g) → int
Returns a copy of color with green overridden.
withRed(int color, int r) → int
Returns a copy of color with red overridden.