UI: Liquid level widget minor improvement

ui-ngx/src/app/shared/components/unit-input.component.ts

@@ -23,8 +23,7 @@ import {
   OnInit,
   ViewChild,
   ViewEncapsulation,
-  Injector,
+  Injector
-  AfterViewInit
 } from '@angular/core';
 import {
   ControlValueAccessor,
@@ -52,7 +51,7 @@ import { ResourcesService } from '@core/services/resources.service';
   ],
   encapsulation: ViewEncapsulation.None
 })
-export class UnitInputComponent implements ControlValueAccessor, OnInit, AfterViewInit {
+export class UnitInputComponent implements ControlValueAccessor, OnInit {
 
   @HostBinding('style.display') get hostDisplay() {return 'flex';};
 
@@ -88,7 +87,7 @@ export class UnitInputComponent implements ControlValueAccessor, OnInit, AfterVi
   }
 
   ngOnInit() {
-    this.unitsFormControl = this.fb.control('', []);
+    this.unitsFormControl = this.fb.control('', this.required ? [Validators.required] : []);
     this.filteredUnits = this.unitsFormControl.valueChanges
       .pipe(
         tap(value => {
@@ -99,12 +98,6 @@ export class UnitInputComponent implements ControlValueAccessor, OnInit, AfterVi
       );
   }
 
-  ngAfterViewInit() {
-    if (this.required) {
-      this.unitsFormControl.setValidators([Validators.required]);
-    }
-  }
-
   writeValue(symbol?: string): void {
     this.searchText = '';
     this.modelValue = symbol;