mirror of
https://github.com/lensapp/lens.git
synced 2025-05-20 05:10:56 +00:00
164 lines
5.8 KiB
Markdown
164 lines
5.8 KiB
Markdown
# Styling an Extension
|
||
|
||
Lens provides a set of global styles and UI components that can be used by any extension to preserve the look and feel of the application.
|
||
|
||
## Layout
|
||
|
||
For layout tasks, Lens uses the [flex.box](https://www.npmjs.com/package/flex.box) library which provides helpful class names to specify some of the [flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_Flexible_Box_Layout/Basic_Concepts_of_Flexbox) properties.
|
||
For example, consider the following HTML and its associated CSS properties:
|
||
|
||
```html
|
||
<div className="flex column align-center"></div>
|
||
```
|
||
|
||
```css
|
||
div {
|
||
display: flex;
|
||
flex-direction: column;
|
||
align-items: center;
|
||
}
|
||
```
|
||
|
||
However, you are free to use any styling technique or framework you like, including [Emotion](https://github.com/emotion-js/emotion) or even plain CSS.
|
||
|
||
### Layout Variables
|
||
|
||
There is a set of CSS variables available for for basic layout needs.
|
||
They are located inside `:root` and are defined in [app.scss](https://github.com/lensapp/lens/blob/master/src/renderer/components/app.scss):
|
||
|
||
```css
|
||
--unit: 8px;
|
||
--padding: var(--unit);
|
||
--margin: var(--unit);
|
||
--border-radius: 3px;
|
||
```
|
||
|
||
These variables are intended to set consistent margins and paddings across components.
|
||
For example:
|
||
|
||
```css
|
||
.status {
|
||
padding-left: calc(var(--padding) * 2);
|
||
border-radius: var(--border-radius);
|
||
}
|
||
```
|
||
|
||
## Themes
|
||
|
||
Lens uses two built-in themes defined in [the themes directory](https://github.com/lensapp/lens/tree/master/src/renderer/themes) – one light and one dark.
|
||
|
||
### Theme Variables
|
||
|
||
When Lens is loaded, it transforms the selected theme's `json` file into a list of [CSS Custom Properties (CSS Variables)](https://developer.mozilla.org/en-US/docs/Web/CSS/Using_CSS_custom_properties).
|
||
This list then gets injected into the `:root` element so that any of the down-level components can use them.
|
||
|
||
|
||
When the user changes the theme, the above process is repeated, and new CSS variables appear, replacing the previous ones.
|
||
|
||
If you want to preserve Lens's native look and feel, with respect to the lightness or darkness of your extension, you can use the provided variables and built-in Lens components such as `Button`, `Select`, `Table`, and so on.
|
||
|
||
There is a set of CSS variables available for extensions to use for theming.
|
||
They are all located inside `:root` and are defined in [app.scss](https://github.com/lensapp/lens/blob/master/src/renderer/components/app.scss):
|
||
|
||
```css
|
||
--font-main: 'Roboto', 'Helvetica', 'Arial', sans-serif;
|
||
--font-monospace: Lucida Console, Monaco, Consolas, monospace;
|
||
--font-size-small: calc(1.5 * var(--unit));
|
||
--font-size: calc(1.75 * var(--unit));
|
||
--font-size-big: calc(2 * var(--unit));
|
||
--font-weight-thin: 300;
|
||
--font-weight-normal: 400;
|
||
--font-weight-bold: 500;
|
||
```
|
||
|
||
as well as in [the theme modules](https://github.com/lensapp/lens/tree/master/src/renderer/themes):
|
||
|
||
```
|
||
--blue: #3d90ce;
|
||
--magenta: #c93dce;
|
||
--golden: #ffc63d;
|
||
--halfGray: #87909c80;
|
||
--primary: #3d90ce;
|
||
--textColorPrimary: #555555;
|
||
--textColorSecondary: #51575d;
|
||
--textColorAccent: #333333;
|
||
--borderColor: #c9cfd3;
|
||
--borderFaintColor: #dfdfdf;
|
||
--mainBackground: #f1f1f1;
|
||
--contentColor: #ffffff;
|
||
--layoutBackground: #e8e8e8;
|
||
--layoutTabsBackground: #f8f8f8;
|
||
--layoutTabsActiveColor: #333333;
|
||
--layoutTabsLineColor: #87909c80;
|
||
...
|
||
```
|
||
|
||
These variables can be used in the following form: `var(--magenta)`.
|
||
For example:
|
||
|
||
```css
|
||
.status {
|
||
font-size: var(--font-size-small);
|
||
background-color: var(--colorSuccess);
|
||
}
|
||
```
|
||
|
||
### Theme Switching
|
||
|
||
When the light theme is active, the `<body>` element gets a "theme-light" class, or: `<body class="theme-light">`.
|
||
If the class isn't there, the theme defaults to dark. The active theme can be changed in the **Preferences** page:
|
||
|
||
|
||
There is a way of detect active theme and its changes in JS. [MobX observer function/decorator](https://github.com/mobxjs/mobx-react#observercomponent) can be used for this purpose.
|
||
|
||
```js
|
||
import React from "react"
|
||
import { observer } from "mobx-react"
|
||
import { App, Component, Theme } from "@k8slens/extensions";
|
||
|
||
@observer
|
||
export class SupportPage extends React.Component {
|
||
render() {
|
||
return (
|
||
<div className="SupportPage">
|
||
<h1>Active theme is {Theme.getActiveTheme().name}</h1>
|
||
</div>
|
||
);
|
||
}
|
||
}
|
||
```
|
||
|
||
`Theme` entity from `@k8slens/extensions` provides active theme object and `@observer` decorator makes component reactive - so it will rerender each time any of the observables (active theme in our case) will be changed.
|
||
|
||
Working example provided in [Styling with Emotion](https://github.com/lensapp/lens-extension-samples/tree/master/styling-emotion-sample) sample extension.
|
||
|
||
## Injected Styles
|
||
|
||
Every extension is affected by the list of default global styles defined in [app.scss](https://github.com/lensapp/lens/blob/master/src/renderer/components/app.scss). These are basic browser resets and element styles, including:
|
||
|
||
- setting the `box-sizing` property for every element
|
||
- default text and background colors
|
||
- default font sizes
|
||
- basic heading (h1, h2, etc) formatting
|
||
- custom scrollbar styling
|
||
|
||
Extensions may overwrite these defaults if needed. They have low CSS specificity, so overriding them should be fairly easy.
|
||
|
||
## CSS-in-JS
|
||
|
||
If an extension uses a system like `Emotion` to work with styles, it can use CSS variables as follows:
|
||
|
||
```javascript
|
||
const Container = styled.div(() => ({
|
||
backgroundColor: 'var(--mainBackground)'
|
||
}));
|
||
```
|
||
|
||
## Examples
|
||
|
||
You can explore samples for each styling technique that you can use for extensions:
|
||
|
||
- [Styling with Sass](https://github.com/lensapp/lens-extension-samples/tree/master/styling-sass-sample)
|
||
- [Styling with Emotion](https://github.com/lensapp/lens-extension-samples/tree/master/styling-emotion-sample)
|
||
- [Styling with CSS Modules](https://github.com/lensapp/lens-extension-samples/tree/master/styling-css-modules-sample)
|