Layouts
Spacer
Bit.BlazorUI
BitSpacer generates space between components inside a flex container. Left alone it is flexible and pushes its neighbours apart; given Width, Height, Gap or Size it becomes a fixed space. It renders one empty element, hidden from assistive technologies.
Usage
Every example is live. Open its code to see exactly what produced the component running underneath.
Basic
With no parameters the spacer is flexible: it takes the room the other children do not need, so one spacer pushes its neighbours to the two ends and several split the room evenly. It is a real flex child, so a container
gap is added on both sides of it.
Title
Start
End
Fixed size
Width is a fixed gap in pixels, Gap the same in any CSS length (
1rem, 5%, var(--my-gap)). A fixed spacer does not grow, and its logical margin never shrinks in a cramped container.
1rem
4ch
10%
end
Vertical
Height is the pixel gap of a column layout, and Vertical moves Gap, Size and MinGap to the block axis. A flexible spacer needs neither: it always grows along the main axis, pinning the last item to the bottom.
Height 8
Height 32
Vertical Gap 3rem
Flexible
Bottom
Grow
Grow is the flex-grow factor (default 1). Several spacers split the leftover room in proportion to it: 1 and 2 give a one third / two thirds split.
A
B
C
A
B
C
Minimum size
MinGap is the floor of a flexible spacer, so its neighbours never touch. Drag the corner of each box to squeeze it: the first spacer keeps its
2rem, the second collapses. A fixed spacer ignores it.
MinGap
2rem
No
MinGap
Element
Element swaps the rendered
div for another tag, such as an li in a list-based toolbar or menu, which only accepts list items.
- Home
- Products
- Sign in
Accessibility
A spacer is
aria-hidden by default, so screen readers skip the empty box. Give it an
AriaLabel when the gap marks a boundary worth announcing: it then renders as a named
separator, announced as vertical, since it divides the items of a row, or as horizontal when it is
Vertical or only given a Height. A flexible spacer dividing a column adds
aria-orientation="horizontal" itself. An explicit role, aria-hidden or
aria-orientation attribute still wins.
Cascading parameters
BitParams hands a BitSpacerParams to every spacer under it, so a toolbar or a page sets its
rhythm once. The values are defaults, not overrides: a spacer that sets a parameter itself keeps its own.
Cascaded
1.5rem
Own Gap
4rem
Outside
Flexible again
Size
Size takes the fixed space from the theme's spacing scale, so it follows the theme's spacing unit and density. It follows Vertical; Gap, Width and Height win over it. Each step is a public CSS variable: the last row re-sizes Large with
--bit-Spacer-large-size.
Small
Medium
Large
End
Vertical Small
Vertical Large
End
Large, re-sized
End
Style & Class
Style and Class land on the spacer element. The space is a margin, so the element has no main-axis size until given one, and it stretches along the cross axis so a decoration shows up in a centered row. Inline styles win over the generated ones.
Style
Class
End
RTL
The fixed space is a logical inline-start margin, so it mirrors with the text direction. Dir on a single spacer moves its space to its other side (the tinted spacers below). A flexible spacer behaves the same either way.
شروع
میانه
پایان
Start
Middle
Start
Middle
CSS variables
The public custom properties this component reads off its root, for what no parameter covers.
Every variable is read with a fallback and never declared by the component, so it inherits like any other custom property:
set one on :root (or in a [bit-theme] block) to restyle every instance, on any ancestor to restyle the ones inside it,
or on the Style of one instance to restyle it - and any instance nested inside it, which inherits the value too; a parameter changes one alone,
as does the real CSS property on the instance's Style / Styles when that property does not inherit (opacity: 1 keeps
one disabled instance undimmed without undimming a disabled one inside it), while an inherited one such as color or
font-family also reaches the nested instances that do not set it themselves. Leave a variable unset and the component
falls back to the theme token beside it.
BitSpacer CSS variables
| Name | Default value | Description |
|---|---|---|
| --bit-Spacer-small-size | 1 theme spacing unit | The fixed space of a spacer with Size Small. |
| --bit-Spacer-medium-size | 2 theme spacing units | The fixed space of a spacer with Size Medium. |
| --bit-Spacer-large-size | 4 theme spacing units | The fixed space of a spacer with Size Large. |
API
Every parameter, public member, sub-class and enum this component exposes.
BitSpacer parameters
| Name | Type | Default value | Description |
|---|---|---|---|
| Element | string? | null | Gets or sets the custom html element used for the root node, "div" by default. This is what lets a spacer sit in a container that only accepts specific children, such as an "li" inside a list-based toolbar or menu, without breaking the markup of that container. |
| Gap | string? | null | Gets or sets the fixed amount of space the spacer generates, using any CSS length value (for example "1rem", "5%", or "var(--my-gap)"). The space is created along the inline (horizontal) axis, or along the block (vertical) axis when Vertical is set. It takes precedence over Width, Height and Size on the axis it targets, and like them it turns the spacer from a flexible one into a fixed one, so Grow and MinGap no longer apply. |
| Grow | string? | null | Gets or sets how much of the leftover space of the container this spacer takes compared to its siblings (the CSS flex-grow factor), 1 by default. Two spacers with the factors "1" and "2" split the leftover space of the container one third to two thirds. It is ignored as soon as the spacer is given a fixed size through Gap, Width, Height or Size. |
| Height | int? | null | Gets or sets the fixed amount of space the spacer generates along the block (vertical) axis, in pixels. This is the parameter to reach for inside a vertical (column) layout, where the inline-axis Width creates no visible space. Setting it turns the spacer from a flexible one into a fixed one, so Grow and MinGap no longer apply. |
| MinGap | string? | null | Gets or sets the smallest amount of space a flexible spacer keeps when the container runs out of room, using any CSS length value. It applies to the inline (horizontal) axis, or to the block (vertical) axis when Vertical is set. It only concerns a flexible spacer, so it is ignored as soon as the spacer is given a fixed size through Gap, Width, Height or Size. |
| Size | BitSize? | null | Gets or sets the fixed amount of space the spacer generates, picked from the spacing scale of the theme, so the resulting length follows the spacing unit and the density of the current theme instead of being hardcoded. It is created along the inline (horizontal) axis, or along the block (vertical) axis when Vertical is set, and like the other fixed sizes it turns the spacer from a flexible one into a fixed one, so Grow and MinGap no longer apply. Gap, Width and Height are more specific, so they take precedence over it. |
| Vertical | bool | false | Gets or sets a value indicating whether Gap, Size and MinGap apply to the block (vertical) axis instead of the inline (horizontal) one. A flexible spacer does not need this parameter: it always grows along the main axis of its container, whichever that is. |
| Width | int? | null | Gets or sets the fixed amount of space the spacer generates along the inline (horizontal) axis, in pixels. The space follows the text direction of the spacer, so in a right-to-left context it is created on the right side. Setting it turns the spacer from a flexible one into a fixed one, so Grow and MinGap no longer apply. |
BitComponentBase parameters
| Name | Type | Default value | Description |
|---|---|---|---|
| AriaLabel | string? | null | Gets or sets the accessible label for the component, used by assistive technologies. |
| Class | string? | null | Gets or sets the CSS class name(s) to apply to the rendered element. |
| Dir | BitDir? | null | Gets or sets the text directionality for the component's content. |
| Disabled | bool | false | Gets or sets a value indicating whether the component is disabled and cannot respond to user interaction. |
| ForceAnimation | bool | false | Gets or sets a value indicating whether the component's animations play at their full duration even when reduced motion is requested. |
| HtmlAttributes | Dictionary<string, object> | new Dictionary<string, object>() | Captures additional HTML attributes to be applied to the rendered element, in addition to the component's parameters. An attribute written on the component wins over an entry of the same name. |
| Id | string? | null | Gets or sets the unique identifier for the component's root element. |
| Style | string? | null | Gets or sets the CSS style string to apply to the rendered element. |
| TabIndex | string? | null | Gets or sets the tab order index for the component when navigating with the keyboard. |
| Visibility | BitVisibility | BitVisibility.Visible | Gets or sets the visibility state (visible, hidden, or collapsed) of the component. |
BitComponentBase public members
| Name | Type | Default value | Description |
|---|---|---|---|
| UniqueId | Guid | Guid.NewGuid() | Gets the readonly unique identifier for the component's root element, assigned when the component instance is constructed. |
| RootElement | ElementReference | Gets the reference to the root HTML element associated with this component. |
BitSize enum
| Name | Value | Description |
|---|---|---|
| Small | 0 | The small size. |
| Medium | 1 | The medium size. |
| Large | 2 | The large size. |
BitVisibility enum
| Name | Value | Description |
|---|---|---|
| Visible | 0 | The content of the component is visible. |
| Hidden | 1 | The content of the component is hidden, but the space it takes on the page remains (visibility:hidden). |
| Collapsed | 2 | The component is hidden (display:none). |
BitDir enum
| Name | Value | Description |
|---|---|---|
| Ltr | 0 | Ltr (left to right) is to be used for languages that are written from the left to the right (like English). |
| Rtl | 1 | Rtl (right to left) is to be used for languages that are written from the right to the left (like Arabic). |
| Auto | 2 | Auto lets the user agent decide. It uses a basic algorithm as it parses the characters inside the element until it finds a character with a strong directionality, then applies that directionality to the whole element. |
Feedback
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