I have an array of boolean for week days to check what day is selected: selectedWeekDays: boolean[] = [true,true,true,true,true,true];

and in .html:

<section>
    <h4>select your days:</h4>
    <mat-checkbox [(ngModel)]="selectedWeekDays[0]">sat</mat-checkbox>
    <mat-checkbox [(ngModel)]="selectedWeekDays[1]">sun</mat-checkbox>
    <mat-checkbox [(ngModel)]="selectedWeekDays[2]">mon</mat-checkbox>
    <mat-checkbox [(ngModel)]="selectedWeekDays[3]">tue</mat-checkbox>
    <mat-checkbox [(ngModel)]="selectedWeekDays[4]">wed</mat-checkbox>
    <mat-checkbox [(ngModel)]="selectedWeekDays[5]">thu</mat-checkbox>
  </section>

but this error is raised for each mat-checkbox: Type 'Event' is not assignable to type 'boolean'. <mat-checkbox [(ngModel)]="selectedWeekDays[2]">sat ... and so on... and also this error: Can't bind to 'ngModel' since it isn't a known property of 'mat-checkbox'.

unfortunately, similar above error I had for radio buttons. why this error is raised and how can fix it? best regards