忘了在哪儿找的啦
viewValue: string[] = [];
carProperties = [
{ value: 'Stereo' },
{
value: 'Radio',
subProperties: [
{ value: 'Digital' },
{ value: 'FM' }
]
}, { value: 'Child seats' },
{ value: 'Rear camera' }
];
valueSelected(value: string): boolean {
return this.viewValue.indexOf(value) !== -1;
}
<div>
test
<mat-form-field>
<mat-select [(value)]="viewValue" multiple>
<ng-container *ngFor="let property of carProperties">
<mat-option [value]="property.value">
{{ property.value }}
</mat-option>
<div *ngIf="property.subProperties && valueSelected(property.value)">
<mat-radio-group>
<mat-radio-button *ngFor="let subProperty of property.subProperties" [value]="subProperty.value" style="display: block; padding: 12px 12px 12px 32px;">
{{ subProperty.value }}
</mat-radio-button>
</mat-radio-group>
</div>
</ng-container>
</mat-select>
</mat-form-field>
</div>
