角度 8 使用表单组添加材料芯片表

Question

我正在尝试添加具有Ng形式的Angular材料的芯片列表。我无法通过单击按钮添加新的芯片列表，并且不知道如何显示新芯片列表芯片列表中添加的数组的值。这是一个例子 https://stackblitz.com/edit/angular-4d5vfj-g1ggqr

<button (click)="addNewChip()">Add new Chip</button><br><br>
<form [formGroup]="myForm">
<mat-form-field class="example-chip-list">
<mat-chip-list #chipList formArrayName="names">
<mat-chip 
*ngFor="let name of myForm.get('names').controls; let i=index;"
[selectable]="selectable"
[removable]="removable"
(removed)="remove(myForm, i)">
{{name.value}}
<mat-icon matChipRemove *ngIf="removable">cancel</mat-icon>
</mat-chip>
<input placeholder="Names"
[matChipInputFor]="chipList"
[matChipInputSeparatorKeyCodes]="separatorKeysCodes"
[matChipInputAddOnBlur]="addOnBlur"
(matChipInputTokenEnd)="add($event, myForm)">
</mat-chip-list>
<mat-error>Atleast 1 name need to be added</mat-error>
</mat-form-field>
</form>

组件.ts 文件

export class ChipListValidationExample implements OnInit {
@ViewChild('chipList') chipList: MatChipList;
public myForm: FormGroup;
// name chips
visible = true;
selectable = true;
removable = true;
addOnBlur = true;
readonly separatorKeysCodes: number[] = [ENTER, COMMA];
// data
data = {
names: ['name1', 'name2']
}
constructor(private fb: FormBuilder) {
this.myForm = this.fb.group({
names: this.fb.array(this.data.names, this.validateArrayNotEmpty)
});
}
ngOnInit() {
this.myForm.get('names').statusChanges.subscribe(
status => this.chipList.errorState = status === 'INVALID'
);
}
initName(name: string): FormControl {
return this.fb.control(name);
}
validateArrayNotEmpty(c: FormControl) {
if (c.value && c.value.length === 0) {
return {
validateArrayNotEmpty: { valid: false }
};
}
return null;
}
add(event: MatChipInputEvent, form: FormGroup): void {
const input = event.input;
const value = event.value;
// Add name
if ((value || '').trim()) {
const control = <FormArray>form.get('names');
control.push(this.initName(value.trim()));
console.log(control);
}
// Reset the input value
if (input) {
input.value = '';
}
}
remove(form, index) {
console.log(form);
form.get('names').removeAt(index);
}
addNewChip(){
console.log("Yse")
this.myForm = this.fb.group({
names: this.fb.array(this.data.names, this.validateArrayNotEmpty)
});
}

}

Answer 1

我希望这就是你要找的

• 修改了addChip，removeChip方法，通过将formControl传递给方法来处理FormArray中的当前Chiplist。
• 修改数据以接受名称和初始值集
• 修改了 addNewChipList 方法以将 formControl 添加到现有的 forArray

<button (click)="addNewChipList()">Add new Chip</button><br><br>
<form [formGroup]="myForm">
<ng-container formArrayName="names"
*ngFor="let item of myForm.get('names').controls; let i = index;">
<mat-form-field class="example-chip-list" [formGroupName]="i">
<mat-chip-list #chipList >
<mat-chip *ngFor="let val of item.value.val"
[selectable]="selectable"
[removable]="removable"
(removed)="removeChip(item, val)">
{{val}}
<mat-icon matChipRemove *ngIf="removable">cancel</mat-icon>
</mat-chip>
<input [placeholder]="item.value.name"
[matChipInputFor]="chipList"
[matChipInputSeparatorKeyCodes]="separatorKeysCodes"
[matChipInputAddOnBlur]="addOnBlur"
(matChipInputTokenEnd)="addChip($event, item)">
</mat-chip-list>
<mat-error>Atleast 1 name need to be added</mat-error>
</mat-form-field>
</ng-container>
</form>

// data
data = {
names: [this.initName('name1'), this.initName('name2', ['A', 'B'])]
}
constructor(private fb: FormBuilder) {
this.myForm = this.fb.group({
names: this.fb.array(this.data.names, this.validateArrayNotEmpty)
});
}
ngOnInit() {
this.myForm.get('names').statusChanges.subscribe(
status => this.chipList.errorState = status === 'INVALID'
);
}
initName(name: string, val: string[]=[]): FormControl {
return this.fb.control({ name, val });
}
validateArrayNotEmpty(c: FormControl) {
if (c.value && c.value.length === 0) {
return {
validateArrayNotEmpty: { valid: false }
};
}
return null;
}
addChip(event: MatChipInputEvent, ctrl: FormControl): void {
const input = event.input;
const value = event.value;
// Add name
if ((value || '').trim()) {
const control = ctrl;
control.value.val.push(value.trim());
console.log(control.value);
}
// Reset the input value
if (input) {
input.value = '';
}
}
removeChip(ctrl, val) {
const idx = ctrl.value.val.findIndex(item => item === val);
ctrl.value.val.splice(idx, 1);
}
addNewChipList() {
const items = this.myForm.get('names') as FormArray;
items.push(this.initName(`name${items.length + 1}`));
}

更新的堆栈闪电战 https://stackblitz.com/edit/angular-4d5vfj-fzjlnm