angular - Inject AbstractControlDirective instance as @ContentChild to custom directive -


i have form control this:

<input formcontrolname="myname" dynamicdisable>

then custom directive:

 @directive({     selector: '[formcontrolname][dynamicdisable]  })  export class dynamicdisabledirective implements aftercontentinit {        @contentchild(abstractcontroldirective) control: any;        ngaftercontentinit(): void {         console.log(this.control);       }     }

i inject directive owner element @contentchild directive. owner elements can type of form control, simple formcontrol, formgroup or formarray. formcontrolname descendant of abstractcontroldirective. why console logs 'undefined' then?

note: when switch abstractcontroldirective ngcontrol this:

@contentchild(ngcontrol) control: any;

everything works expected, form control instance gets injected , logged well. however, approach can used simple formcontrol, not groups , arrays.

as far know there nothing provided abstractcontroldirective, therefore querying or injecting 1 not work without further assistance.

i haven't tried, might work register alias providers 

@directive({     selector: '[formcontrolname][dynamicdisable],     providers: [      { provide: abstractcontroldirective, useexisting: formcontrol, usemulti: true },      { provide: abstractcontroldirective, useexisting: formgroup, usemulti: true },     ] })

with usemulti: true able (to of them), list if there more 1 match , filter list want.


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