⚠️ Warning

This library is a fork of ngx-treeview that is compatible with Angular 16, 17, 18, and 19. This fork does not have the intention to continue the support of this library and comes with no guarantees. Please use at your own discretion.

ngx-treeview

An Angular treeview component with checkbox

Latest Updates

Version 19.0.0 - Angular 19 Compatibility

• Upgraded to Angular 19
• Updated dependencies and peer dependencies
• All tests passing with Angular 19

Dependencies

• Angular ^19.0.0
• Lodash ^4.17.21
• Bootstrap 4 (for styling)

This component is currently supporting Bootstrap 4. If you are using Bootstrap 4 alpha 6, please downgrade to the older version 1.0.10.

You can customize CSS yourself to break down dependencies to Bootstrap.

Features

• Unlimited tree level
• State: disabled / collapse, expand
• Filtering
• Internationalization (i18n) support
• Template
• Checkbox with tri-state

Demo

https://leovo2708.github.io/ngx-treeview/

Installation

After install the above dependencies, install @samotics/ngx-treeview via:

npm install @samotics/ngx-treeview --save

Version Compatibility:

• Angular 19: Use @samotics/[email protected]
• Angular 18: Use @samotics/[email protected]
• Angular 17: Use @samotics/[email protected]
• Angular 16: Use @samotics/[email protected]

Once installed you need to import our main module in your application module:

import { TreeviewModule } from '@samotics/ngx-treeview';

@NgModule({
  declarations: [AppComponent, ...],
  imports: [TreeviewModule.forRoot(), ...],
  bootstrap: [AppComponent]
})
export class AppModule {
}

Usage

Treeview:

<ngx-treeview
  [config]="config"
  [items]="items"
  (selectedChange)="onSelectedChange($event)"
  (filterChange)="onFilterChange($event)"
>
</ngx-treeview>

Treeview with dropdown:

<ngx-dropdown-treeview
  [buttonClass]="buttonClass"
  [config]="config"
  [items]="items"
  (selectedChange)="onSelectedChange($event)"
  (filterChange)="onFilterChange($event)"
>
</ngx-dropdown-treeview>

config is optional. This is the default configuration:

{
   hasAllCheckBox: true,
   hasFilter: false,
   hasCollapseExpand: false,
   decoupleChildFromParent: false,
   maxHeight: 500
}

You can change default configuration easily because TreeviewConfig is injectable.

Pipe ngxTreeview:

To map your JSON objects to TreeItem objects.

<ngx-dropdown-treeview
  [config]="config"
  [items]="items | ngxTreeview:'textField'"
  (selectedChange)="onSelectedChange($event)"
>
</ngx-dropdown-treeview>

Create a TreeviewItem:

const itCategory = new TreeviewItem({
  text: "IT",
  value: 9,
  children: [
    {
      text: "Programming",
      value: 91,
      children: [
        {
          text: "Frontend",
          value: 911,
          children: [
            { text: "Angular 1", value: 9111 },
            { text: "Angular 2", value: 9112 },
            { text: "ReactJS", value: 9113 },
          ],
        },
        {
          text: "Backend",
          value: 912,
          children: [
            { text: "C#", value: 9121 },
            { text: "Java", value: 9122 },
            { text: "Python", value: 9123, checked: false },
          ],
        },
      ],
    },
    {
      text: "Networking",
      value: 92,
      children: [
        { text: "Internet", value: 921 },
        { text: "Security", value: 922 },
      ],
    },
  ],
});

You can pass the second paramater 'autoCorrectChecked' with value=true (default is false) in constructor of TreeviewItem to correct checked value of it and all of its descendants. In some cases, you need to push or pop children flexibly, checked of parent may be not correct. Then you need to call function correctChecked() to help to correct from root to its descendants.

const vegetableCategory = new TreeviewItem({
  text: "Vegetable",
  value: 2,
  children: [
    { text: "Salad", value: 21 },
    { text: "Potato", value: 22 },
  ],
});
vegetableCategory.children.push(
  new TreeviewItem({ text: "Mushroom", value: 23, checked: false })
);
vegetableCategory.correctChecked(); // need this to make 'Vegetable' node to change checked value from true to false

TreeviewEventParser:

Extract data from list of checked TreeviewItem and send it in parameter of event selectedChange. Some built-in TreeviewEventParser:

• DefaultTreeviewEventParser: return values of checked items.
• DownlineTreeviewEventParser: return list of checked items in orginal order with their ancestors.
• OrderDownlineTreeviewEventParser: return list of checked items in checked order with their ancestors. Note that: value of a leaf must be different from value of other leaves.

Templating:

See example 4 & 5.

Contributing

I am very appreciate for your ideas, proposals and found bugs which you can leave in github issues. Thanks in advance!