bootstrap-less-port/less/mixins/_forms.less

A Less port of Bootstrap v4

// Form control focus state
//
// Generate a customized focus state and for any input with the specified color,
// which defaults to the `@input-focus-border-color` variable.
//
// We highly encourage you to not customize the default value, but instead use
// this to tweak colors on an as-needed basis. This aesthetic change is based on
// WebKit's default styles, but applicable to a wider range of browsers. Its
// usability and accessibility should be taken into account with any change.
//
// Example usage: change the default blue border and shadow to white for better
// contrast against a dark gray background.
#form-control-focus(@ignore-warning: false) {
	&:focus {
		color: @input-focus-color;
		background-color: @input-focus-bg;
		border-color: @input-focus-border-color;
		outline: 0;
		& when (@enable-shadows) {
			#box-shadow(@input-box-shadow, @input-focus-box-shadow);
		}
		& when not (@enable-shadows) {
			// Avoid using mixin so we can pass custom focus shadow properly
			box-shadow: @input-focus-box-shadow;
		}
	}
	#deprecate("The `#form-control-focus()` mixin", "v4.4.0", "v5", @ignore-warning);
}

// This mixin uses an `if()` technique to be compatible with Dart Sass
// See https://github.com/sass/sass/issues/1873#issuecomment-152293725 for more details
//@mixin form-validation-state-selector($state) {
//  @if ($state == "valid" or $state == "invalid") {
//    .was-validated #{if(&, "&", "")}:#{$state},
//    #{if(&, "&", "")}.is-#{$state} {
//      @content;
//    }
//  } @else {
//    #{if(&, "&", "")}.is-#{$state} {
//      @content;
//    }
//  }
//}
// LESS PORT: The `if` technique mentioned above is not used here because it’s unnecessary.
#form-validation-state-selector(@state, @content) {
	& when ((@state = valid) or (@state = invalid)) {
		.was-validated &:@{state},
		&.is-@{state} {
			@content();
		}
	}
	& when not ((@state = valid) or (@state = invalid)) {
		&.is-@{state} {
			@content();
		}
	}
}

#form-validation-state(@state, @color, @icon) {
	.@{state}-feedback {
		display: none;
		width: 100%;
		margin-top: @form-feedback-margin-top;
		#font-size(@form-feedback-font-size);
		color: @color;
	}

	.@{state}-tooltip {
		position: absolute;
		top: 100%;
		z-index: 5;
		display: none;
		max-width: 100%; // Contain to parent when possible
		padding: @form-feedback-tooltip-padding-y @form-feedback-tooltip-padding-x;
		margin-top: 0.1rem;
		#font-size(@form-feedback-tooltip-font-size);
		line-height: @form-feedback-tooltip-line-height;
		color: color-yiq(@color);
		background-color: fade(@color, (@form-feedback-tooltip-opacity * 100));
		#border-radius(@form-feedback-tooltip-border-radius);
	}

	#form-validation-state-selector(@state, {
		~ .@{state}-feedback,
		~ .@{state}-tooltip {
			display: block;
		}
	});

	.form-control {
		#form-validation-state-selector(@state, {
			border-color: @color;

			& when (@enable-validation-icons) {
				padding-right: @input-height-inner;
				background-image: escape-svg(@icon);
				background-repeat: no-repeat;
				background-position: right @input-height-inner-quarter center;
				background-size: @input-height-inner-half @input-height-inner-half;
			}

			&:focus {
				border-color: @color;
				box-shadow: 0 0 0 @input-focus-width fade(@color, 25%);
			}
		});
	}

	textarea.form-control {
		#form-validation-state-selector(@state, {
			& when (@enable-validation-icons) {
				padding-right: @input-height-inner;
				background-position: top @input-height-inner-quarter right @input-height-inner-quarter;
			}
		});
	}

	.custom-select {
		#form-validation-state-selector(@state, {
			border-color: @color;

			& when (@enable-validation-icons) {
				padding-right: @custom-select-feedback-icon-padding-right;
				background: @custom-select-background, escape-svg(@icon) @custom-select-bg no-repeat ~"@{custom-select-feedback-icon-position}/@{custom-select-feedback-icon-size}";
			}

			&:focus {
				border-color: @color;
				box-shadow: 0 0 0 @input-focus-width fade(@color, 25%);
			}
		});
	}

	.form-check-input {
		#form-validation-state-selector(@state, {
			~ .form-check-label {
				color: @color;
			}

			~ .@{state}-feedback,
			~ .@{state}-tooltip {
				display: block;
			}
		});
	}

	.custom-control-input {
		#form-validation-state-selector(@state, {
			~ .custom-control-label {
				color: @color;

				&::before {
					border-color: @color;
				}
			}

			&:checked {
				~ .custom-control-label::before {
					border-color: lighten(@color, 10%);
					#gradient-bg(lighten(@color, 10%));
				}
			}

			&:focus {
				~ .custom-control-label::before {
					box-shadow: 0 0 0 @input-focus-width fade(@color, 25%);
				}

				&:not(:checked) ~ .custom-control-label::before {
					border-color: @color;
				}
			}
		});
	}

	// custom file
	.custom-file-input {
		#form-validation-state-selector(@state, {
			~ .custom-file-label {
				border-color: @color;
			}

			&:focus {
				~ .custom-file-label {
					border-color: @color;
					box-shadow: 0 0 0 @input-focus-width fade(@color, 25%);
				}
			}
		});
	}
}