如何使用material2数据表

Question

我正在尝试实现Material2数据表.但我无法理解如何以正确的方式使用它.

import {Component, ElementRef, ViewChild} from '@angular/core';
import {DataSource} from '@angular/cdk';
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';
import 'rxjs/add/operator/debounceTime';
import 'rxjs/add/operator/distinctUntilChanged';
import 'rxjs/add/observable/fromEvent';

@Component({
  selector: 'table-filtering-example',
  styleUrls: ['table-filtering-example.css'],
  templateUrl: 'table-filtering-example.html',
})
export class TableFilteringExample {
  displayedColumns = ['userId', 'userName', 'progress', 'color'];
  exampleDatabase = new ExampleDatabase();
  dataSource: ExampleDataSource | null;

  @ViewChild('filter') filter: ElementRef;

  ngOnInit() {
    this.dataSource = new ExampleDataSource(this.exampleDatabase);
    Observable.fromEvent(this.filter.nativeElement, 'keyup')
        .debounceTime(150)
        .distinctUntilChanged()
        .subscribe(() => {
          if (!this.dataSource) { return; }
          this.dataSource.filter = this.filter.nativeElement.value;
        });
  }
}

/** 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> {
  _filterChange = new BehaviorSubject('');
  get filter(): string { return this._filterChange.value; }
  set filter(filter: string) { this._filterChange.next(filter); }

  constructor(private _exampleDatabase: ExampleDatabase) {
    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._filterChange,
    ];

    return Observable.merge(...displayDataChanges).map(() => {
      return this._exampleDatabase.data.slice().filter((item: UserData) => {
        let searchStr = (item.name + item.color).toLowerCase();
        return searchStr.indexOf(this.filter.toLowerCase()) != -1;
      });
    });
  }

  disconnect() {}
}

以上是数据表的代码,对我来说非常混乱.甚至他们的文档也很差.有人能解释一下上面代码的流程是什么吗？

如果您觉得问题太基本无法问,请忽略？

Answer 1

您的示例中的代码是通用表的定义,使用material2规范中的新cdk组件.你必须记住md-table它的可视化实现cdk-table,因此你需要声明一个cdk,其模型与HTML中的md-model兼容.

例如:

我声明了cdk-table以下实现:

1. 首先,依赖:

Material2中的新CDK组件,使用:

import { DataSource } from '@angular/cdk';
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';

1. TS中HTML结构的定义:

我定义了一个displayedColumns数组,这些项是我的HTML表中的列,按顺序:

displayedColumns = ['userId', 'userName', 'progress'];

类型的数据库ExampleDatabase(特定于手动定义的对象):

exampleDatabase = new ExampleDatabase();

最后,我宣布一个dataSource,这是我数据的来源.它是一个手动定义或数据为null的对象.

dataSource: ExampleDataSource | null;

在ngOnInit()方法中,我只是声明我的参数为my dataSource的新ExampleDataSource参数exampleDataBase.

好,现在实现其余的代码:

首先,声明一个接口DataBase.这对于保持数据的一致性非常重要,数据库必须遵守已定义的方案.在此示例中,数据库有三列:id,name和progress:

export interface UserData {
  id: number;
  name: string;
  progress: string;
}

接下来的一点是创建一个类(Object)ExampleDatabase,其中包含我的数据定义DataBase.您可以创建用于连接到实际数据库(PostgreSQL,MongoDB)的服务,获取真实数据并在另一种方法中为cdk-datatable创建对象,但是在此示例中,我们使用在运行时模拟的内存数据库.

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() {

    return {
      id: 1,
      name: 'example',
      progress: Math.round(Math.random() * 100).toString()
    };
  }
}

好的,最后我用my的定义创建了第二个类DataSource.

export class ExampleDataSource extends DataSource<any> {
  constructor(private _exampleDatabase: ExampleDatabase) {
    super();
  }

  /** Connect function called by the table to retrieve one stream containing the data to render. */
  connect(): Observable<UserData[]> {
    return this._exampleDatabase.dataChange;
  }

  disconnect() { }
}

此方法确保数据格式正确,并释放与DataBase(在内存中)的"连接" 以获取其中的数据.

最后,使用HTML中的md-table组件或cdk-table组件.该md-table组件使用材料设计风格,并cdk-table使用通用样式..

MD-表:

<div class="example-container mat-elevation-z8">
  <md-table #table [dataSource]="dataSource">

    <!-- ID Column -->
    <ng-container cdkColumnDef="userId">
      <md-header-cell *cdkHeaderCellDef> ID </md-header-cell>
      <md-cell *cdkCellDef="let row"> {{row.id}} </md-cell>
    </ng-container>

    <!-- Progress Column -->
    <ng-container cdkColumnDef="progress">
      <md-header-cell *cdkHeaderCellDef> Progress </md-header-cell>
      <md-cell *cdkCellDef="let row"> {{row.progress}}% </md-cell>
    </ng-container>

    <!-- Name Column -->
    <ng-container cdkColumnDef="userName">
      <md-header-cell *cdkHeaderCellDef> Name </md-header-cell>
      <md-cell *cdkCellDef="let row"> {{row.name}} </md-cell>
    </ng-container>

    <md-header-row *cdkHeaderRowDef="displayedColumns"></md-header-row>
    <md-row *cdkRowDef="let row; columns: displayedColumns;"></md-row>
  </md-table>
</div>

CDK-表:

<div class="example-container mat-elevation-z8">
  <cdk-table #table [dataSource]="dataSource" class="example-table">

    <!-- ID Column -->
    <ng-container cdkColumnDef="userId">
      <cdk-header-cell *cdkHeaderCellDef class="example-header-cell"> ID </cdk-header-cell>
      <cdk-cell *cdkCellDef="let row" class="example-cell"> {{row.id}} </cdk-cell>
    </ng-container>

    <!-- Progress Column -->
    <ng-container cdkColumnDef="progress">
      <cdk-header-cell *cdkHeaderCellDef class="example-header-cell"> Progress </cdk-header-cell>
      <cdk-cell *cdkCellDef="let row" class="example-cell"> {{row.progress}}% </cdk-cell>
    </ng-container>

    <!-- Name Column -->
    <ng-container cdkColumnDef="userName">
      <cdk-header-cell *cdkHeaderCellDef class="example-header-cell"> Name </cdk-header-cell>
      <cdk-cell *cdkCellDef="let row" class="example-cell"> {{row.name}} </cdk-cell>
    </ng-container>

    <cdk-header-row *cdkHeaderRowDef="displayedColumns" class="example-header-row"></cdk-header-row>
    <cdk-row *cdkRowDef="let row; columns: displayedColumns;" class="example-row"></cdk-row>
  </cdk-table>
</div>

其余的实现,搜索,菜单,复选框等是您负责实现操作信息的逻辑.

有关更多详细信息,请使用有关cdk-table的文档:

https://material.angular.io/guide/cdk-table

结果:

做我的佩剑和成就,我理解我的解释,并为我的英语道歉.我在学习.

Answer 2

这是为查看出勤创建的自定义代码,现在我已对数据进行了硬编码,您可以调用服务而不是获取动态数据.

app.component.ts

import { Component, OnInit, ElementRef, ViewEncapsulation, ViewChild } from '@angular/core';
import { DataSource } from '@angular/cdk';
import { BehaviorSubject } from 'rxjs/BehaviorSubject';
import { Observable } from 'rxjs/Observable';
import { MdPaginator, MdSort } from '@angular/material';
import 'rxjs/add/operator/startWith';
import 'rxjs/add/observable/merge';
import 'rxjs/add/operator/map';
declare let d3: any;

@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.css']
})


export class AppComponent implements OnInit {

  displayedColumns = ['shiftDate', 'swipeIn', 'swipeOut', 'duration', 'status'];
  exampleDatabase = new ExampleDatabase();
  dataSource: ExampleDataSource | null;

  @ViewChild(MdPaginator) paginator: MdPaginator;
  @ViewChild(MdSort) sort: MdSort;

  ngOnInit() {
    this.dataSource = new ExampleDataSource(this.exampleDatabase, this.paginator, this.sort);
  }
}

export interface attendanceData {
  shiftDate: string;
  swipeIn: string;
  swipeOut: string;
  duration: string;
  status: 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<attendanceData[]> = new BehaviorSubject<attendanceData[]>([]);
  get data(): attendanceData[] {

    let data = [
      {
        "shiftDate": "17-July-2017",
        "swipeIn": "10:00 AM",
        "swipeOut": "06:00 PM",
        "duration": "8 Hours",
        "status": "PRESENT"

      },
      {
        "shiftDate": "16-July-2017",
        "swipeIn": "9:00 AM",
        "swipeOut": "5:00 AM",
        "duration": "7 Hours",
        "status": "PRESENT"
      }

    ];

    return data;
  }

  constructor() {

    this.dataChange.next(this.data);
  }

}

export class ExampleDataSource extends DataSource<any> {
  _filterChange = new BehaviorSubject('');
  get filter(): string { return this._filterChange.value; }
  set filter(filter: string) { this._filterChange.next(filter); }

  constructor(private _exampleDatabase: ExampleDatabase, private _paginator: MdPaginator, private _sort: MdSort) {
    super();
  }

  /** Connect function called by the table to retrieve one stream containing the data to render. */
  connect(): Observable<attendanceData[]> {
    const displayDataChanges = [
      this._exampleDatabase.dataChange,
      this._paginator.page,
      this._sort.mdSortChange
    ];

    return Observable.merge(...displayDataChanges).map(() => {
      // const data = this._exampleDatabase.data.slice();
      const data = this.getSortedData();
      // Grab the page's slice of data.
      const startIndex = this._paginator.pageIndex * this._paginator.pageSize;
      return data.splice(startIndex, this._paginator.pageSize);
    });
  }

  disconnect() { }

  getSortedData(): attendanceData[] {
    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 'shiftDate': [propertyA, propertyB] = [a.shiftDate, b.shiftDate]; break;
        case 'swipeIn': [propertyA, propertyB] = [a.swipeIn, b.swipeIn]; break;
        case 'swipeOut': [propertyA, propertyB] = [a.swipeOut, b.swipeOut]; break;
        case 'duration': [propertyA, propertyB] = [a.duration, b.duration]; break;
      }

      let valueA = isNaN(+propertyA) ? propertyA : +propertyA;
      let valueB = isNaN(+propertyB) ? propertyB : +propertyB;

      return (valueA < valueB ? -1 : 1) * (this._sort.direction == 'asc' ? 1 : -1);
    });
  }
}

app.component.html

<div class="example-container mat-elevation-z8">
  <md-table #table [dataSource]="dataSource" mdSort>
    <!--- 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 cdkColumnDef="shiftDate">
      <md-header-cell *cdkHeaderCellDef md-sort-header> Shift Date </md-header-cell>
      <md-cell *cdkCellDef="let row"> {{row.shiftDate}} </md-cell>
    </ng-container>

    <!-- Progress Column -->
    <ng-container cdkColumnDef="swipeIn">
      <md-header-cell *cdkHeaderCellDef md-sort-header> Swipe In </md-header-cell>
      <md-cell *cdkCellDef="let row"> {{row.swipeIn}}% </md-cell>
    </ng-container>

    <!-- Name Column -->
    <ng-container cdkColumnDef="swipeOut">
      <md-header-cell *cdkHeaderCellDef> Swipe Out </md-header-cell>
      <md-cell *cdkCellDef="let row"> {{row.swipeOut}} </md-cell>
    </ng-container>

    <!-- Color Column -->
    <ng-container cdkColumnDef="duration">
      <md-header-cell *cdkHeaderCellDef>Duration</md-header-cell>
      <md-cell *cdkCellDef="let row"> {{row.duration}} </md-cell>
    </ng-container>


    <!-- Color Column -->
    <ng-container cdkColumnDef="status">
      <md-header-cell *cdkHeaderCellDef>Status</md-header-cell>
      <md-cell *cdkCellDef="let row"> {{row.status}} </md-cell>
    </ng-container>

    <md-header-row *cdkHeaderRowDef="displayedColumns"></md-header-row>
    <md-row *cdkRowDef="let row; columns: displayedColumns;"></md-row>
  </md-table>

    <md-paginator #paginator
                [length]="exampleDatabase.data.length"
                [pageIndex]="0"
                [pageSize]="25"
                [pageSizeOptions]="[5, 10, 25, 100]">
  </md-paginator>

</div>

app.module.ts

import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
import { BrowserModule } from '@angular/platform-browser';
import { BrowserAnimationsModule } from '@angular/platform-browser/animations';
import { NgModule } from '@angular/core';
import { MaterialModule, MdTableModule  } from '@angular/material';
import { FlexLayoutModule } from '@angular/flex-layout';
import { CdkTableModule } from '@angular/cdk';


import { AppComponent } from './app.component';



@NgModule({
  declarations: [
    AppComponent,
  ],
  imports: [
    BrowserAnimationsModule,
    CdkTableModule,
    BrowserModule,
    MaterialModule, MdTableModule,
    FlexLayoutModule
  ],
  providers: [],
  bootstrap: [AppComponent]
})
export class AppModule { }