Title | Added | Status | Last reviewed |
---|---|---|---|
Card View Update service |
v2.0.0 |
Active |
2022-11-25 |
Reports edits and clicks within fields of a Card View component.
Implements BaseCardViewUpdate
.
You can use the Card View Update service to respond to edits and clicks within items on a card view. This might involve updating application data to reflect the changes made to the view or could simply be a matter of highlighting a clicked item.
The service is injected into a component using a constructor parameter, which also creates a corresponding property in the object:
properties: any;
constructor(private cardViewUpdateService: CardViewUpdateService) {
this.properties = [
new CardViewTextItemModel({
label: 'Name',
value: 'Kirk',
key: 'name',
default: 'No name entered',
multiline: false,
editable: true,
clickable: true
}),
new CardViewTextItemModel({
label: 'Rank',
value: 'Captain',
key: 'rank',
default: 'No rank entered',
multiline: false,
editable: true,
clickable: true
}),
new CardViewTextItemModel({
label: 'Ship',
value: 'Enterprise',
key: 'ship',
default: 'No ship entered',
multiline: false,
editable: true,
clickable: true
})
];
}
The constructor here also sets the CardViewTextItemModel
instances that define the layout of the
card view (see the Card View component for further information
about this). The model objects and the key
property are used to identify which item has been clicked
or updated when an event occurs.
You must subscribe to the service to be informed about clicks and updates. You can do this by
registering your own functions with the service's itemUpdated$
and itemClicked$
events
(place this code in the ngOnInit
lifecycle hook rather than the constructor):
ngOnInit() {
this.cardViewUpdateService.itemUpdated$.subscribe(this.respondToCardUpdate.bind(this));
this.cardViewUpdateService.itemClicked$.subscribe(this.respondToCardClick.bind(this));
}
With the subscriptions in place, respondToCardUpdate
and respondToCardClick
will now be
called after updates and clicks, respectively.
The update function is passed a parameter of type UpdateNotification
:
export interface UpdateNotification {
target: any;
changed: any;
}
Here, target
contains the CardViewTextItemModel
that was used to initialize
the field in question (in practice, this might be a CardViewDateItemModel
or CardViewMapItemModel
if
the card layout includes these objects). The changed
property contains an object with a single property:
{ keyValue: 'Value after editing' }
Here, keyValue
is actually the value of the key
field specified when the item was initialized. So
in our example, if the third item was edited from 'Enterprise' to 'Shuttle Craft', the object would be:
{ ship: 'Shuttle Craft' }
The complete code for respondToCardUpdate
might look something like the following:
respondToCardUpdate(un: UpdateNotification) {
this.updateMessage = un.target.label + ' changed to ' + un.changed[un.target.key];
}
Note that the function will only be called if the editable
property of the model object is set to true
for this item. Also, the editable
value of all items will be overridden if editable
is set to false
on the Card View component itself.
The click function is passed a ClickNotification
object, which is similar to UpdateNotification
described above,
but without the changed
property. Use the target
property to identify the item that was clicked:
respondToCardClick(cn: ClickNotification) {
this.clickMessage = cn.target.label + ' was just clicked';
}
Note that this function will only be called if the clickable
property of the model object is set to true for this item.
updateElement
function helps to update the card view item. It takes the CardViewBaseItemModel
type object as parameter.
Example
this.cardViewUpdateService.updateElement(cardViewBaseItemModel)