This section explains how to create a simple ComboBox component and configure its available functionalities in Angular.
The following list of dependencies are required to use the ComboBox component in your application.
|-- @syncfusion/ej2-angular-dropdowns
|-- @syncfusion/ej2-base
|-- @syncfusion/ej2-data
|-- @syncfusion/ej2-angular-base
|-- @syncfusion/ej2-dropdowns
|-- @syncfusion/ej2-lists
|-- @syncfusion/ej2-inputs
|-- @syncfusion/ej2-navigations
|-- @syncfusion/ej2-popups
|-- @syncfusion/ej2-buttons
Angular provides the easiest way to set angular CLI projects using Angular CLI
tool.
Install the CLI application globally to your machine.
npm install -g @angular/cli
ng new syncfusion-angular-combobox
By default, it install the CSS style base application. To setup with SCSS, pass —style=scss argument on create project.
Example code snippet.
ng new syncfusion-angular-combobox --style=scss
Navigate to the created project folder.
cd syncfusion-angular-combobox
All the available Essential JS 2 packages are published in npmjs.com
registry.
To install ComboBox component, use the following command.
npm install @syncfusion/ej2-angular-dropdowns --save
(or)
npm i @syncfusion/ej2-angular-dropdowns --save
The —save will instruct NPM to include the ComboBox package inside of the dependencies section of the
package.json
.
Import ComboBox module into Angular application(app.module.ts) from the package @syncfusion/ej2-angular-dropdowns
.
import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
// import the ComboBoxModule for the ComboBox component
import { ComboBoxModule } from '@syncfusion/ej2-angular-dropdowns';
import { AppComponent } from './app.component';
@NgModule({
//declaration of ej2-angular-dropdowns module into NgModule
imports: [ BrowserModule, ComboBoxModule ],
declarations: [ AppComponent ],
bootstrap: [ AppComponent ]
})
export class AppModule { }
The following CSS files are available in ../node_modules/@syncfusion
package folder.
This can be referenced in [src/styles.css] using following code.
@import '../node_modules/@syncfusion/ej2-base/styles/material.css';
@import '../node_modules/@syncfusion/ej2-buttons/styles/material.css';
@import '../node_modules/@syncfusion/ej2-dropdowns/styles/material.css';
@import '../node_modules/@syncfusion/ej2-inputs/styles/material.css';
@import '../node_modules/@syncfusion/ej2-popups/styles/material.css';
@import '../node_modules/@syncfusion/ej2-lists/styles/material.css';
@import '../node_modules/@syncfusion/ej2-angular-dropdowns/styles/material.css';
Modify the template in [src/app/app.component.ts] file to render the ComboBox component.
Add the Angular ComboBox by using <ejs-combobox>
selector in template
section of the app.component.ts file.
import { Component } from '@angular/core';
@Component({
selector: 'app-root',
// specifies the template string for the ComboBox component
template: `<ejs-combobox id='comboelement'></ejs-combobox>`
})
export class AppComponent { }
After initializing, populate the ComboBox with data using the dataSource
property.
Here, an array of string values passed to ComboBox component.
import { Component } from '@angular/core';
@Component({
selector: 'app-root',
// specifies the template string for the ComboBox component
template: `<ejs-combobox id='comboelement' [dataSource]='data'></ejs-combobox>`
})
export class AppComponent {
constructor() {
}
// defined the array of data
public data: string[] = ['Cricket', 'Football', 'Rugby', 'Snooker', 'Tennis'];
}
After completing the configuration required to render a basic ComboBox, run the following command to display the output in your default browser.
ng serve
The following example illustrates the output in your browser.
import { Component } from '@angular/core';
@Component({
selector: 'app-root',
// specifies the template string for the ComboBox component with dataSource
template: `<ejs-combobox id='comboelement' [dataSource]='data' placeholder = 'Select a game'></ejs-combobox>`
})
export class AppComponent {
constructor() {
}
// defined the array of data
public data: string[] = ['Cricket', 'Football', 'Rugby', 'Snooker', 'Tennis'];
}
import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import { FormsModule, ReactiveFormsModule } from '@angular/forms';
import { ComboBoxModule } from '@syncfusion/ej2-angular-dropdowns';
import { ButtonModule } from '@syncfusion/ej2-angular-buttons';
/**
* Module
*/
@NgModule({
imports: [
BrowserModule,FormsModule, ReactiveFormsModule, ComboBoxModule,ButtonModule
],
declarations: [AppComponent],
bootstrap: [AppComponent]
})
export class AppModule { }
import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
import { enableProdMode } from '@angular/core';
import { AppModule } from './app.module';
enableProdMode();
platformBrowserDynamic().bootstrapModule(AppModule);
The ComboBox allows the user to give input as custom value which is not required to present in predefined set of values. By default, this support is enabled by allowCustom property. In this case, both text field and value field considered as same. The custom value will be sent to post back handler when a form is about to be submitted.
import { Component } from '@angular/core';
@Component({
selector: 'app-root',
// specifies the template string for the ComboBox component with dataSource
template: `<ejs-combobox id='comboelement' [dataSource]='sportsData' [fields]=fields allowCustom=true placeholder = 'Select a game'></ejs-combobox>`
})
export class AppComponent {
constructor() {
}
public fields: Object = {text: 'Game', value: 'Id'};
// defined the array of data
public sportsData: { [key: string]: Object }[] = [
{ Id: 'game1', Game: 'Badminton' },
{ Id: 'game2', Game: 'Football' },
{ Id: 'game3', Game: 'Tennis' }
];
}
import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import { FormsModule, ReactiveFormsModule } from '@angular/forms';
import { ComboBoxModule } from '@syncfusion/ej2-angular-dropdowns';
import { ButtonModule } from '@syncfusion/ej2-angular-buttons';
/**
* Module
*/
@NgModule({
imports: [
BrowserModule,FormsModule, ReactiveFormsModule, ComboBoxModule,ButtonModule
],
declarations: [AppComponent],
bootstrap: [AppComponent]
})
export class AppModule { }
import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
import { enableProdMode } from '@angular/core';
import { AppModule } from './app.module';
enableProdMode();
platformBrowserDynamic().bootstrapModule(AppModule);
By default, the width of the popup list automatically adjusts according to the ComboBox input element’s width, and the height of the popup list has ‘300px’.
The height and width of the popup list can also be customized using the popupHeight and popupWidth property respectively.
In the following sample, popup list’s width and height are configured.
import { Component } from '@angular/core';
@Component({
selector: 'app-root',
// specifies the template string for the ComboBox component with value property
template: `<ejs-combobox id='comboelement' #samples [dataSource]='data' placeholder='Select a game' popupHeight='200px' popupWidth='250px'></ejs-combobox>`
})
export class AppComponent {
constructor() {
}
// define the array of data
public data: string[] = ['Cricket', 'Football', 'Golf', 'Rugby', 'Snooker', 'Tennis'];
}
import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import { FormsModule, ReactiveFormsModule } from '@angular/forms';
import { ComboBoxModule } from '@syncfusion/ej2-angular-dropdowns';
import { ButtonModule } from '@syncfusion/ej2-angular-buttons';
/**
* Module
*/
@NgModule({
imports: [
BrowserModule,FormsModule, ReactiveFormsModule, ComboBoxModule,ButtonModule
],
declarations: [AppComponent],
bootstrap: [AppComponent]
})
export class AppModule { }
import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
import { enableProdMode } from '@angular/core';
import { AppModule } from './app.module';
enableProdMode();
platformBrowserDynamic().bootstrapModule(AppModule);
In ComboBox, the value
property supports two-way binding functionality.
The following example demonstrates how to work the two-way binding functionality in ComboBox.
import { Component } from '@angular/core';
@Component({
selector: 'app-root',
// specifies the template string for the ComboBox component and
// input element for checking the two-way binding support using value property
template: `
<ejs-combobox id='comboelement' [dataSource]='data' [(value)]='value' placeholder="Select a game"></ejs-combobox>
<div style='margin-top: 50px'>
<input type="text" [(ngModel)]="value" style='width:245px;height:25px' />
</div>
`
})
export class AppComponent {
constructor() {
}
// defined the array of complex data
public data: string[] = [ 'Badminton', 'Football', 'Rugby', 'Snooker', 'Tennis' ];
// set a value to pre-select
public value: string = 'Badminton';
}
import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import { FormsModule, ReactiveFormsModule } from '@angular/forms';
import { ComboBoxModule } from '@syncfusion/ej2-angular-dropdowns';
import { ButtonModule } from '@syncfusion/ej2-angular-buttons';
/**
* Module
*/
@NgModule({
imports: [
BrowserModule,FormsModule, ReactiveFormsModule, ComboBoxModule,ButtonModule
],
declarations: [AppComponent],
bootstrap: [AppComponent]
})
export class AppModule { }
import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
import { enableProdMode } from '@angular/core';
import { AppModule } from './app.module';
enableProdMode();
platformBrowserDynamic().bootstrapModule(AppModule);