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docs(core): update deprecations guide (#30644) 

PR Close #30644
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Kara Erickson 2019-05-23 13:46:25 -07:00 committed by Jason Aden
parent 9b035e4038
commit 250887244e
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aio/content/guide/deprecations.md
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@ -317,24 +317,7 @@ We expect to remove the polyfill from most if not all CLI projects via an `ng up
{@a static-query-resolution}
### `@ViewChild()` / `@ContentChild()` static resolution as the default
The API docs have always recommended searching for `ViewChild()` query results in
the `ngAfterViewInit()` hook at the earliest and searching for
`ContentChild()` query results in the `ngAfterContentInit()` hook at the earliest.
However, in practice, `@ViewChild()` and `@ContentChild()` queries are sometimes
resolved earlier in the lifecycle (that is, before change detection runs) if the
results are not influenced by bindings (for example, some results are
embedded in an `*ngIf` or `*ngFor`).
This default resolution behavior is deprecated. In a future version of Angular, all queries will be resolved only before their guaranteed hooks by default.
If you do need to access the `ViewChild()` or `ContentChild()` value
before change detection runs (for example, in `ngOnInit()`), you can
use a static flag as in the following example:
```
@ViewChild('foo', {static: true}) foo !: ElementRef;
```
See our [dedicated migration guide for static queries](guide/static-query-migration).
{@a contentchild-input-together}
### `@ContentChild()` / `@Input()` used together