【发布时间】：2017-10-23 15:33:05
【问题描述】：
我正在尝试让 mat-table 排序在本地工作，虽然我可以让数据按预期显示，但单击标题行不会像在在线示例中那样进行排序（在全部）。
我试图让这个演示在本地工作：
https://material.angular.io/components/sort/overview
https://plnkr.co/edit/XF5VxOSEBxMTd9Yb3ZLA?p=preview
我使用 Angular CLI 生成了一个新项目，然后按照以下步骤操作： https://material.angular.io/guide/getting-started
这是我的本地文件：
app.module.ts
import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';
import { MatSort, MatTableModule } from '@angular/material';
import { AppComponent } from './app.component';
import { TableSortingExample } from './table-sorting-example';
@NgModule({
declarations: [
AppComponent,
TableSortingExample,
MatSort
],
imports: [
BrowserModule,
MatTableModule
],
providers: [],
bootstrap: [AppComponent]
})
export class AppModule { }
app.component.ts
import { Component } from '@angular/core';
@Component({
selector: 'app-root',
templateUrl: './app.component.html',
styleUrls: ['./app.component.css']
})
export class AppComponent {
title = 'app';
}
app.component.html
<div style="text-align:center">
<h1>
Welcome to {{title}}!
</h1>
<table-sorting-example></table-sorting-example>
</div>
table-sorting-example.html
<div class="example-container mat-elevation-z8">
<mat-table #table [dataSource]="dataSource" matSort>
<!--- Note that these columns can be defined in any order.
The actual rendered columns are set as a property on the row definition" -->
<!-- ID Column -->
<ng-container matColumnDef="userId">
<mat-header-cell *matHeaderCellDef mat-sort-header> ID </mat-header-cell>
<mat-cell *matCellDef="let row"> {{row.id}} </mat-cell>
</ng-container>
<!-- Progress Column -->
<ng-container matColumnDef="progress">
<mat-header-cell *matHeaderCellDef mat-sort-header> Progress </mat-header-cell>
<mat-cell *matCellDef="let row"> {{row.progress}}% </mat-cell>
</ng-container>
<!-- Name Column -->
<ng-container matColumnDef="userName">
<mat-header-cell *matHeaderCellDef mat-sort-header> Name </mat-header-cell>
<mat-cell *matCellDef="let row"> {{row.name}} </mat-cell>
</ng-container>
<!-- Color Column -->
<ng-container matColumnDef="color">
<mat-header-cell *matHeaderCellDef mat-sort-header> Color </mat-header-cell>
<mat-cell *matCellDef="let row" [style.color]="row.color"> {{row.color}} </mat-cell>
</ng-container>
<mat-header-row *matHeaderRowDef="displayedColumns"></mat-header-row>
<mat-row *matRowDef="let row; columns: displayedColumns;"></mat-row>
</mat-table>
</div>
<!-- Copyright 2017 Google Inc. All Rights Reserved.
Use of this source code is governed by an MIT-style license that
can be found in the LICENSE file at http://angular.io/license -->
table-sorting-example.ts
import {Component, ViewChild} from '@angular/core';
import {DataSource} from '@angular/cdk/collections';
import {MatSort} from '@angular/material';
import {BehaviorSubject} from 'rxjs/BehaviorSubject';
import {Observable} from 'rxjs/Observable';
import 'rxjs/add/operator/startWith';
import 'rxjs/add/observable/merge';
import 'rxjs/add/operator/map';
/**
* @title Table with sorting
*/
@Component({
selector: 'table-sorting-example',
styleUrls: ['table-sorting-example.css'],
templateUrl: 'table-sorting-example.html',
})
export class TableSortingExample {
displayedColumns = ['userId', 'userName', 'progress', 'color'];
exampleDatabase = new ExampleDatabase();
dataSource: ExampleDataSource | null;
@ViewChild(MatSort) sort: MatSort;
ngOnInit() {
this.dataSource = new ExampleDataSource(this.exampleDatabase, this.sort);
}
}
/** Constants used to fill up our data base. */
const COLORS = ['maroon', 'red', 'orange', 'yellow', 'olive', 'green', 'purple',
'fuchsia', 'lime', 'teal', 'aqua', 'blue', 'navy', 'black', 'gray'];
const NAMES = ['Maia', 'Asher', 'Olivia', 'Atticus', 'Amelia', 'Jack',
'Charlotte', 'Theodore', 'Isla', 'Oliver', 'Isabella', 'Jasper',
'Cora', 'Levi', 'Violet', 'Arthur', 'Mia', 'Thomas', 'Elizabeth'];
export interface UserData {
id: string;
name: string;
progress: string;
color: string;
}
/** An example database that the data source uses to retrieve data for the table. */
export class ExampleDatabase {
/** Stream that emits whenever the data has been modified. */
dataChange: BehaviorSubject<UserData[]> = new BehaviorSubject<UserData[]>([]);
get data(): UserData[] { return this.dataChange.value; }
constructor() {
// Fill up the database with 100 users.
for (let i = 0; i < 100; i++) { this.addUser(); }
}
/** Adds a new user to the database. */
addUser() {
const copiedData = this.data.slice();
copiedData.push(this.createNewUser());
this.dataChange.next(copiedData);
}
/** Builds and returns a new User. */
private createNewUser() {
const name =
NAMES[Math.round(Math.random() * (NAMES.length - 1))] + ' ' +
NAMES[Math.round(Math.random() * (NAMES.length - 1))].charAt(0) + '.';
return {
id: (this.data.length + 1).toString(),
name: name,
progress: Math.round(Math.random() * 100).toString(),
color: COLORS[Math.round(Math.random() * (COLORS.length - 1))]
};
}
}
/**
* Data source to provide what data should be rendered in the table. Note that the data source
* can retrieve its data in any way. In this case, the data source is provided a reference
* to a common data base, ExampleDatabase. It is not the data source's responsibility to manage
* the underlying data. Instead, it only needs to take the data and send the table exactly what
* should be rendered.
*/
export class ExampleDataSource extends DataSource<any> {
constructor(private _exampleDatabase: ExampleDatabase, private _sort: MatSort) {
super();
}
/** Connect function called by the table to retrieve one stream containing the data to render. */
connect(): Observable<UserData[]> {
const displayDataChanges = [
this._exampleDatabase.dataChange,
this._sort.sortChange,
];
return Observable.merge(...displayDataChanges).map(() => {
return this.getSortedData();
});
}
disconnect() {}
/** Returns a sorted copy of the database data. */
getSortedData(): UserData[] {
const data = this._exampleDatabase.data.slice();
if (!this._sort.active || this._sort.direction == '') { return data; }
return data.sort((a, b) => {
let propertyA: number|string = '';
let propertyB: number|string = '';
switch (this._sort.active) {
case 'userId': [propertyA, propertyB] = [a.id, b.id]; break;
case 'userName': [propertyA, propertyB] = [a.name, b.name]; break;
case 'progress': [propertyA, propertyB] = [a.progress, b.progress]; break;
case 'color': [propertyA, propertyB] = [a.color, b.color]; break;
}
let valueA = isNaN(+propertyA) ? propertyA : +propertyA;
let valueB = isNaN(+propertyB) ? propertyB : +propertyB;
return (valueA < valueB ? -1 : 1) * (this._sort.direction == 'asc' ? 1 : -1);
});
}
}
/** Copyright 2017 Google Inc. All Rights Reserved.
Use of this source code is governed by an MIT-style license that
can be found in the LICENSE file at http://angular.io/license */
有没有人知道为什么它会像在线表格一样显示但缺少排序功能？
【问题讨论】：
-
我会先调试应用程序。有什么错误吗？运行
ng test --sm=false看看会发生什么。 -
没有@ViewChild(MatSort) sort: MatSort; 对我有用有什么原因吗？