vue-visibility-sensor
v0.3.0
Published
Sensor component for Vue that notifies you when it goes in or out of the window viewport.
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Vue Visibility Sensor
Sensor component for Vue that notifies you when it goes in or out of the window viewport.
Inspired by React Visibility Sensor
Install
npm install vue-visibility-sensor
This component is recommended to use in Vue-cli SPA project. Because it doesn't build as any bundle like AMD or UMD.
It's just a single file component.
Example
Try building an example yourself locally, here's another:
To run the example locally:
npm run example
- open
example/index.html
in a browser
General usage goes something like:
const VisibilitySensor = require('vue-visibility-sensor');
// with children
new Vue({
components: {
VisibilitySensor,
},
template: `
<VisibilitySensor @change="onChange">
<div>...optional content goes here...</div>
</VisibilitySensor>
`,
methods: {
onChange(isVisible) {
console.log('Element is now %s', isVisible ? 'visible' : 'hidden');
}
}
});
// without children
new Vue({
components: {
VisibilitySensor,
},
template: `
<VisibilitySensor @change="onChange">
</VisibilitySensor>
`,
methods: {
onChange(isVisible) {
console.log('Element is now %s', isVisible ? 'visible' : 'hidden');
}
}
});
Event
change
: the event name emitted from sensor whenever the element changes from being within the window viewport or not. Event name is'change'
, all in lower case. Function is called with 1 argument(isVisible: boolean)
Props
|Name|Default Value|Description|
|:-:|:-:|:-|
|active|true
| boolean flag for enabling / disabling the sensor. When active !== true
the sensor will not fire the onChange
callback.|
|partialVisibility|false
| consider element visible if only part of it is visible. Also possible values are - 'top', 'right', 'bottom', 'left' - in case it's needed to detect when one of these become visible explicitly.|
|offset|{}
| with offset you can define amount of px from one side when the visibility should already change. So in example setting offset={{top:10}}
means that the visibility changes hidden when there is less than 10px to top of the viewport. Offset works along with partialVisibility
|
|minTopValue|0
| consider element visible if only part of it is visible and a minimum amount of pixels could be set, so if at least 100px are in viewport, we mark element as visible.|
|intervalCheck|true
| when this is true, it gives you the possibility to check if the element is in view even if it wasn't because of a user scroll|
|intervalDelay|100
| integer, number of milliseconds between checking the element's position in relation the the window viewport. Making this number too low will have a negative impact on performance.|
|scrollCheck|false
| by making this true, the scroll listener is enabled.|
|scrollDelay|250
| the debounce rate at which the check is triggered. Ex: 250ms after the user stopped scrolling.|
|scrollThrottle|-1
| by specifying a value > -1, you are enabling throttle instead of the delay to trigger checks on scroll event. Throttle supercedes delay.|
|resizeCheck|false
| by making this true, the resize listener is enabled. Resize listener only listens to the window.|
|resizeDelay|250
| is the debounce rate at which the check is triggered. Ex: 250ms after the user stopped resizing.|
|resizeThrottle|-1
| by specifying a value > -1, you are enabling throttle instead of the delay to trigger checks on resize event. Throttle supercedes delay.|
|delayedCall|false
| if is set to true, wont execute on page load ( prevents react apps triggering elements as visible before styles are loaded )|
|containment| window
| element to use as a viewport when checking visibility. Default behaviour is to use the browser window as viewport.|
|children| <span></span>
| can be a template or vue component|
It's possible to use both intervalCheck
and scrollCheck
together. This means you can detect most visibility changes quickly with scrollCheck
, and an intervalCheck
with a higher intervalDelay
will act as a fallback for other visibility events, such as resize of a container.
Thanks
Special thanks to Josh Johnston
License
MIT