npm package: @ksungur/angular2-multiselect-dropdown
Description: Angular Multiselct dropdown component library for Angular version 11, 10, 9,8,6,4 
Author: Kutayberk Sungur
Latest version: 5.0.6

# Angular 2/4/6/8 Multiselect Dropdown
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[![downloads](https://img.shields.io/npm/dt/angular2-multiselect-dropdown.svg)](https://www.npmjs.com/package/angular2-multiselect-dropdown)
[![license](https://img.shields.io/github/license/cuppalabs/angular2-multiselect-dropdown.svg)](https://www.npmjs.com/package/angular2-multiselect-dropdown)

Angular 2 multiselect dropdown component for web applications. Easy to integrate and use.

![](https://cuppalabs.github.io/angular2-multiselect-dropdown/assets/img/multiselect.jpeg)

# Important Notice !! 
#####  From v3.0.0 onwards, you need to include `default.theme.css` file to get the basic styling of the dropdown. Refer to `themes and theming` section below


# [Documentation](http://cuppalabs.github.io/components/multiselectDropdown) | [Demos / Examples](https://cuppalabs.github.io/angular2-multiselect-dropdown).

## Table of Contents
##### 1. Getting Started
##### 2. Installation
##### 3. Usage
##### 4  Theming 
##### 5. Templates
##### 6. Template Driven Forms support
##### 7. Reactive Forms support
##### 8. Settings configuration
##### 9. Callbacks and events
##### 10. Lazy lodaing - handle large data lists
##### 11. Group By feature
##### 12. Search filter for both plain list and grouped list
##### 13. Custom Search / Search API





## Getting Started
### Installation
- The Mutiselect Dropdown package is published on the [npm](https://www.npmjs.com/package/angular2-multiselect-dropdown) Registry. 
- Install the package :
    `npm install angular2-multiselect-dropdown`

- Once installed import `AngularMultiSelectModule` from the installed package into your module as follows:

### Usage
Import `AngularMultiSelectModule` into `NgModule` in `app.module.ts`. Angular's `FormsModule` is also required.
```js
import { AngularMultiSelectModule } from 'angular2-multiselect-dropdown';
import { FormsModule } from '@angular/forms';

@NgModule({
  // ...
  imports: [
    AngularMultiSelectModule,
    FormsModule
  ]
  // ...
})

```

Declare the component data variables and options in your component where you want to consume the dropdown component.

```js

import { Component, OnInit } from '@angular/core';

export class AppComponent implements OnInit {
    dropdownList = [];
    selectedItems = [];
    dropdownSettings = {};
    ngOnInit(){
        this.dropdownList = [
                              {"id":1,"itemName":"India"},
                              {"id":2,"itemName":"Singapore"},
                              {"id":3,"itemName":"Australia"},
                              {"id":4,"itemName":"Canada"},
                              {"id":5,"itemName":"South Korea"},
                              {"id":6,"itemName":"Germany"},
                              {"id":7,"itemName":"France"},
                              {"id":8,"itemName":"Russia"},
                              {"id":9,"itemName":"Italy"},
                              {"id":10,"itemName":"Sweden"}
                            ];
        this.selectedItems = [
                                {"id":2,"itemName":"Singapore"},
                                {"id":3,"itemName":"Australia"},
                                {"id":4,"itemName":"Canada"},
                                {"id":5,"itemName":"South Korea"}
                            ];
        this.dropdownSettings = { 
                                  singleSelection: false, 
                                  text:"Select Countries",
                                  selectAllText:'Select All',
                                  unSelectAllText:'UnSelect All',
                                  enableSearchFilter: true,
                                  classes:"myclass custom-class"
                                };            
    }
    onItemSelect(item:any){
        console.log(item);
        console.log(this.selectedItems);
    }
    OnItemDeSelect(item:any){
        console.log(item);
        console.log(this.selectedItems);
    }
    onSelectAll(items: any){
        console.log(items);
    }
    onDeSelectAll(items: any){
        console.log(items);
    }
}
```

Add the following component tag in you template 
```html
<angular2-multiselect [data]="dropdownList" [(ngModel)]="selectedItems" 
    [settings]="dropdownSettings" 
    (onSelect)="onItemSelect($event)" 
    (onDeSelect)="OnItemDeSelect($event)"
    (onSelectAll)="onSelectAll($event)"
    (onDeSelectAll)="onDeSelectAll($event)"></angular2-multiselect>

```

### Themes and Theming

- From v3.0.0 onwards, you need to include `default.theme.css` file to get the basic styling of the dropdown. 
- The component package has a themes folder in node_modules at `angular2-multiselect-dropdown\themes\default.theme.css`
- Include the `default.theme.css` in `angular-cli.json` (for versions below angular 6) and `angular.json` (for version 6 or more).
- [Refer this file](https://github.com/CuppaLabs/angular2-multiselect-dropdown/blob/master/angular.json) on how to add the css file to your angular project.

You can create your own theme from now on. You can have a look at example scss theming file at [Default theme](https://github.com/CuppaLabs/angular2-multiselect-dropdown/tree/master/src/themes/default.theme.scss) 


### Template - For custom html of menu item

```html
<angular2-multiselect [data]="dropdownList" [(ngModel)]="selectedItems" [settings]="dropdownSettings">
  <c-item>
          <ng-template let-item="item">
            <label style="color: #333;min-width: 150px;">{{item.itemName}}</label>
            <img [src]="item.image" style="width: 30px; border: 1px solid #efefef;margin-right: 20px;" />
            <label>Capital - {{item.capital}}</label>
          </ng-template>
  </c-item>    
</angular2-multiselect>

```

### Template - For custom html of Selected item - badge

```html
<angular2-multiselect [data]="dropdownList" [(ngModel)]="selectedItems" [settings]="dropdownSettings">
  <c-badge>
           <ng-template let-item="item">
            <label style="margin: 0px;">{{item.itemName}}</label>
            <img [src]="item.image" style="width: 16px; margin-right: 5px;" />
           </ng-template>
  </c-badge>  
</angular2-multiselect>

```

### Template Driven Forms support

```html

<form (ngSubmit)="onSubmit()" #loginForm="ngForm" style="border: 1px solid #ccc; padding: 10px;">
        <div class="form-group">
            <label for="name">Skills</label>
            <angular2-multiselect [data]="itemList" [(ngModel)]="formModel.skills" 
                                  [settings]="settings" 
                                  (onSelect)="onItemSelect($event)"
                                  (onDeSelect)="OnItemDeSelect($event)" 
                                  (onSelectAll)="onSelectAll($event)" 
                                  (onDeSelectAll)="onDeSelectAll($event)" name="skills">
            </angular2-multiselect>
        </div>
</form>

```

```js

formModel = {
        name: '',
        email: 'ascasc@aa.com',
        skills: [{ "id": 1, "itemName": "Angular" }]
    };

```

### Reactive Forms support

```html

<form [formGroup]="userForm" novalidate style="border: 1px solid #ccc; padding: 10px;">
        <div class="form-group">
            <label for="name">Skills</label>
           <angular2-multiselect [data]="itemList" [(ngModel)]="selectedItems" 
                                  [settings]="settings" 
                                  (onSelect)="onItemSelect($event)"
                                  (onDeSelect)="OnItemDeSelect($event)" 
                                  (onSelectAll)="onSelectAll($event)" 
                                  (onDeSelectAll)="onDeSelectAll($event)" formControlName="skills">
            </angular2-multiselect>
        </div>
</form>

```

```js
userForm: FormGroup;
this.userForm = this.fb.group({
            name: '',
            email: ['', Validators.required],
            skills: [[], Validators.required]
        });

```

### Settings
The following list of settings are supported by the component. Configure the settings to meet your requirement.

| Setting         |Type    | Description            | Default Value |
|:--- |:--- |:--- |:--- |
| singleSelection | Boolean | To set the dropdown for single item selection only. | false |
| text | String | Text to be show in the dropdown, when no items are selected. | 'Select' |
| enableCheckAll | Boolean | Enable the option to select all items in list | false |
| selectAllText | String | Text to display as the label of select all option | Select All |
| unSelectAllText | String | Text to display as the label of unSelect option | UnSelect All |
| enableSearchFilter | Boolean | Enable filter option for the list. | false |
| enableFilterSelectAll | Boolean | A 'select all' checkbox to select all filtered results.  | true |
| filterSelectAllText | String | Text to display as the label of select all option | Select all filtered results |
| filterUnSelectAllText | String | Text to display as the label of unSelect option | UnSelect all filtered results |
| maxHeight | Number | Set maximum height of the dropdown list in px. | 300 |
| badgeShowLimit | Number | Limit the number of badges/items to show in the input field. If not set will show all selected. | All |
| classes | String | Custom classes to the dropdown component. Classes are added to the dropdown selector tag. To add multiple classes, the value should be space separated class names.| '' |
| limitSelection | Number | Limit the selection of number of items from the dropdown list. Once the limit is reached, all unselected items gets disabled. | none |
| disabled | Boolean | Disable the dropdown | false |
| searchPlaceholderText | String | Custom text for the search placeholder text. Default value would be 'Search' | 'Search' |
| groupBy | String | Name of the field by which the list should be grouped. | none |
| selectGroup | Boolean | Select a group at once. GroupBy should be enabled, to use this. | false |
| searchAutofocus | Boolean | Autofocus search input field| true |
| labelKey | String | The property name which should be rendered as label in the dropdown| itemName |
| primaryKey | String | The property by which the object is identified. Default is 'id'.| id |
| position | String | Set the position of the dropdown list to 'top' or 'bottom'| bottom |
| noDataLabel | String | Label text when no data is available in the list| 'No Data Available' |
| searchBy | Array | Search the list by certain properties of the list item. Ex: ["itemName, "id","name"]. Deafult is , it will search the list by all the properties of list item | [] |
| lazyLoading | Boolean | Enable lazy loading. Used to render large datasets. | false |
| showCheckbox | Boolean | Show or hide checkboxes in the list | true |
| addNewItemOnFilter | Boolean | Whe you filter items and if, the item is not found, you can add the text as new item to the list | false |
| addNewButtonText | String | The text in the button when `addNewItemOnFilter` is enabled | 'Add' |
| escapeToClose | boolean | Press excape key to close the dropdown | true |
| autoPosition | boolean | Enable dropdown to open either on 'top' or 'bottom' Ex: settings = { position: 'bottom', autoPosition: false }; open the dropdown always at bottom |  true |
| tagToBody | boolean | If the dropdown to be appended to body or not ? | true |

### Events
- `onSelect` - Return the selected item on selection.
    Example : (onSelect)="onItemSelect($event)"
- `onDeSelect` - Return the un-selected item on un-selecting.
    Example : (onDeSelect)="OnItemDeSelect($event)"
- `onSelectAll` - Return the list of all selected items.
    Example : (onSelectAll)="onSelectAll($event)"
- `onDeSelectAll` - Returns an empty array.
    Example : (onDeSelectAll)="onDeSelectAll($event)"
- `onGroupSelect` - Returns the selected group items as an array.
    Example: (onGroupSelect)="onGroupSelect($event)"
- `onGroupDeSelect` - Returns the sun-elected group items as an array.
    Example: (onGroupDeSelect)="onGroupDeSelect($event)"
- `onOpen` - Callback method fired after the dropdown opens
    Example : (onOpen)="onOpen($event)"
- `onClose` - Callback method, fired when the dropdown is closed
    Example : (onClose)="onClose($event)"
- `onScrollToEnd` - Callback event fired when the dropdown list is scrolled to the end. Usually used with virtual scrolling, to load data on      scroll.
    Example : (onScrollToEnd)="fetchMore($event)"
- `onAddFilterNewItem` - Callback event fired when you click the `Add` button which will appear when `addNewItemOnFilter` setting is enabled.
    Example : (onAddFilterNewItem)="onAddItem($event)"
- `onFilterSelectAll` - Callback event fired when the list is filtered and all filtered items are selected with select all filtered items checkbox.
    Example : (onFilterSelectAll)="onFilterSelectAll($event)"
- `onFilterDeSelectAll` - Callback event fired when the list is filtered and all filtered items are de-selected with de-select all filtered items checkbox.
    Example : (onFilterDeSelectAll)="onFilterDeSelectAll($event)"

## Run locally
- Clone the repository or downlod the .zip,.tar files.
- Run `npm install`
- Run `ng serve` for a dev server
- Navigate to `http://localhost:4200/`
 The app will automatically reload if you change any of the source files.

## License
MIT License.