Previously, the emitEvent flag was only checked when emitting on the current control.
Thus, if the control was part of a hierarchy, events were emitted on the parent and the childrens.
This fixes the issue by properly passing the emitEvent flag to both parent and childrens.
Fixes#12366
PR Close#21018
This commit adds support for setting default `updateOn` values
in `FormGroups` and `FormArrays`. If you set `updateOn` to
’blur’` at the group level, all child controls will default to `’blur’`,
unless the child has explicitly specified a different `updateOn` value.
```
const c = new FormGroup({
one: new FormControl()
}, {updateOn: blur});
```
It's worth noting that parent groups will always update their value and
validity immediately upon value/validity updates from children. In other
words, if a group is set to update on blur and its children are individually
set to update on change, the group will still update on change with its
children; its default value will simply not be used.
By default, the value and validation status of a `FormControl` updates
whenever its value changes. If an application has heavy validation
requirements, updating on every text change can sometimes be too expensive.
This commit introduces a new option that improves performance by delaying
form control updates until the "blur" event. To use it, set the `updateOn`
option to `blur` when instantiating the `FormControl`.
```ts
// example without validators
const c = new FormControl(, { updateOn: blur });
// example with validators
const c= new FormControl(, {
validators: Validators.required,
updateOn: blur
});
```
Like in AngularJS, setting `updateOn` to `blur` will delay the update of
the value as well as the validation status. Updating value and validity
together keeps the system easy to reason about, as the two will always be
in sync. It's also worth noting that the value/validation pipeline does
still run when the form is initialized (in order to support initial values).
Closes#7113
FormControls, FormGroups, and FormArrays now optionally accept an options
object as their second argument. Validators and async validators can be
passed in as part of this options object (though they can still be passed
in as the second and third arg as before).
```ts
const c = new FormControl(, {
validators: [Validators.required],
asyncValidators: [myAsyncValidator]
});
```
This commit also adds support for passing arrays of validators and async
validators to FormGroups and FormArrays, which formerly only accepted
individual functions.
```ts
const g = new FormGroup({
one: new FormControl()
}, [myPasswordValidator, myOtherValidator]);
```
This change paves the way for adding more options to AbstractControls,
such as more fine-grained control of validation timing.
Observable subscriptions from previous validation runs should be canceled
before a new subscription is created for the next validation run.
Currently the subscription that sets the errors is canceled properly,
but the source observable created by the validator is not. While this
does not affect validation status or error setting, the source
observables will incorrectly continue through the pipeline until they
complete. This change ensures that the whole stream is canceled.
AsyncValidatorFn previously had an "any" return type, but now it more
explicitly requires a Promise or Observable return type. We don't
anticipate this causing problems given that any other return type
would have caused a runtime error already.