Weex provide the ability to let events trigger action, like starting a JavaScript when a user click on a component. Below are the common event attributes that can be added to weex components to define event actions.
### Event penetration
> The principle of native event delivery under Android and iOS is different, only for iOS here.
When a parent view has multiple peer views, iOS will select the highest level View to respond to the event, and the underlying view event will never be responded.
Weex add attribute `eventPenetrationEnabled` to `
` component. When the value is `true`(default would be `false`), the view's children views still respond to the event normally, while the view itself will not respond to the event, but pass the event to the lower level View.
### View interactivity
Weex add attribute `userInteractionEnabled` to `
` component. When the value is `false`(default would be `true`), neither the view nor its children views respond to the event. The event is passed to the lower layer View.
**longpress**
If a `longpress` event is bound to a component, the event will be triggered when user long press on it.
**event object**
|key |value |备注 |
|-- |-- |-- |
|type |longpress| |
|target | |The target component where the event is triggered |
|timestamp| |Timestamp when event is triggered |
**Appear**
If a appear event is bound to a component inside a scrollable container, the event will be triggered when the component comes to be visible.
**event object**
|key |value |notes |
|-- |-- |-- |
|type |appear | |
|target | |The target component where the event is triggered |
|timestamp | |Timestamp when event is triggered|
|direction | ```up```or ```down``` |The direction in which the scroller is scrolling. |
**Disappear**
If a `disappear` event is bound to a component inside a scrollable container, the event will be triggered when the component scrolls out of viewport and disappears from your sight.
**event object**
|key |value |备注 |
|-- |-- |-- |
|type |disappear | |
|target | |The target component where the event is triggered |
|timestamp| |Timestamp when event is triggered|
|direction| ```up```or ```down``` |The direction in which the scroller is scrolling. Could be `up` or `down` |