angular - Nativescript - 我的组件中不存在 ChangeDetectorRef

Question

我尝试自动更新 ListView 中使用的数组。为此，我使用 ChangeDetectorRef，如下所示:

import { Component, OnInit, ChangeDetectionStrategy, Input, ChangeDetectorRef } from "@angular/core";

@Component({
    selector: "register",
    templateUrl: "./register.html",
    styleUrls: ["./register.css"],
    changeDetection: ChangeDetectionStrategy.OnPush
})

export class RegisterComponent implements OnInit {

@Input regis = Array<string>;

constructor(cdr: ChangeDetectorRef){}

ngAfterContentChecked() {
    this.cdr.detectChanges();
}

但是，我收到此错误:

error TS2339: Property 'cdr' does not exist on type 'RegisterComponent'.

有人可以解释一下我的误解吗？

Answer 1

它是构造函数中的局部变量，直到您添加像 public/private 这样的访问器。

import { Component, OnInit, ChangeDetectionStrategy, Input, ChangeDetectorRef } from "@angular/core";

@Component({
    selector: "register",
    templateUrl: "./register.html",
    styleUrls: ["./register.css"],
    changeDetection: ChangeDetectionStrategy.OnPush
})

export class RegisterComponent implements OnInit {

@Input regis = Array<string>;

constructor(private cdr: ChangeDetectorRef){}

ngAfterContentChecked() {
    this.cdr.detectChanges();
}