Why writeValue called after detroy component which implements ControlValueAccessor?

Question

I have implemented ControlValueAccessor in my own primitive component. Its code you see: there (plunker)

In parent component, I use my with ng-if directive. I can hide and show my component through checkbox. Component inits and destroys each times but writeValue function call a lot of times. Please check my code at plunker

Why is this happening? How I can fix this issue?

Bazinga Bazinga · Accepted Answer · 2018-01-20T21:23:40

You need to recreate the control:

  resetValue() {
    this.name = new FormControl('initial');
    this.name.setValue('has been reset');
  }

As @Сергей mentioned the reason is because every time when ControlValueAccessor component created, it register its callback functions in private property of formControl (for example, _onChange). This is array, which accumulate these functions. One of the solutions is creating new FormControl.

Why writeValue called after detroy component which implements ControlValueAccessor?

1 Answers