Tree-Vue

A light-weight library for management of hierachical content. Most solutions I found did not offer the depth of flexibility I needed with the tree. I decided to solve my problem and also give back to the Vue community. Feel free to log issues, I will jump on them at the slightest opportunity. 😊

Features

1. :heavy_check_mark: Hierachical rendering of content.
2. ✔️ Subscribing to items checked event (based on type)
3. :heavy_check_mark: Moving Items between folders (drag-and-drop)
4. :heavy_check_mark: Customising Item Rendering based on item type
5. ✔️ Rendering selectable items like checkboxes or plain content
6. ✔️ Double clicking to rename item

Features in Development

1. Programmatically toggle item visibility based on the type property.
2. Sorting items alphametically or grouping based on types
3. Disabling and Enabling Item(s)
4. Programmatically determining what item can be dragged into another item.
5. -Custom Context Menu depending on item type.

Basic Component Rendering

 <template>
    <tree-view :treeViewItems="treeViewNodes" />
</template>

 <script lang='ts'>
import { Vue, Component} from 'vue-property-decorator';

import { TreeViewItem, ItemTypes } from '@/businessLogic/contracts/types';

@Component
export default class App extends Vue {
  treeViewNodes: TreeViewItem[] = []
}

Item Schema

 export interface TreeViewItem {
    children?: TreeViewItem[]
    type: string
    checkedStatus?: CheckedState,
    name: string,
    id: string,
    parentId?: string
}

How to use Advance

Custom Icon Based on Item Type.

You can customise item based on their type property.

 <template>
  <tree-view :treeViewItems="treeViewNodes">
      <template v-slot:icon="treeViewItem">
          <img src="@/assets/folder.svg" alt="folder" v-if="treeViewItem.type === 'folder'" >
          <img src="@/assets/word.png" alt="vue-logo" v-else-if="treeViewItem.type === '.doc'" height="22" width="22">
          <img src="@/assets/excel.png" alt="vue-logo" v-else-if="treeViewItem.type === '.excel'" height="22" width="22">
      </template>
  </tree-view>
</template>

Advanced Customisation

The library provides a way to further customise the tree view by listening to the v-on:created event from the tree-view component. The payload surplied provides robust set of options for configuring the tree.

Schema of CreatedEvent Payload

     export interface TreeViewCreatedEventPayload {
        itemCustomisations: ItemTypeCustomisations;
        eventManager: EventManager
        ...
    }

Schema for ItemTypeCustomisations

 export interface ItemTypeCustomisations {
    isDropValid(droppedNode: TreeViewItem, dropHost: TreeViewItem): boolean;
    makeItemsCheckable(types: string[]): void;
    registerItemRenamedHandler(type: string, callback: (renamedItem: TreeViewItem) => Promise<TreeViewItem>): void;
    registerDragAndDropValidator(canItemMoveCallBack: (movingItem: TreeViewItem, destinationItem: TreeViewItem) => boolean): void;
    disableDragAndDrop(): void;
    
    getCustomisation(type: string): Customisations;
    getRenameHandler(type: string): (item: TreeViewItem) => Promise<TreeViewItem>;

    registerItemDeletedHandler(type: string, callback: (item: TreeViewItem) => Promise<boolean>): void;
    registerItemMovedHandler(callBack: (movedItem: TreeViewItem) => Promise<TreeViewItem>): void;
    
    registerAnyItemDeleted(callback: (item: TreeViewItem) => Promise<boolean>): void;
    registerAnyItemRenamed(callback: (item: TreeViewItem) => Promise<TreeViewItem>): void;
    registerAnyItemDragAndDrop(): void;
}

Example

 <template>
  <tree-view :treeViewItems="treeViewNodes" @created="customiseTreeView" />
</template>

 <script lang='ts'>
import { Vue, Component} from 'vue-property-decorator';

import { TreeViewCreatedEventPayload, TreeViewItem } from '@/businessLogic/contracts/types';

@Component
export default class App extends Vue {
  
  // This method is called when the tree view is created (on Created hook). And allows you to customise the tree-view items using the payload passed into the function.

  customiseTreeView(treeCreatedEvent: TreeViewCreatedEventPayload) {
    const customisations = treeCreatedEvent.itemCustomisations;
    
    // `Tree-vue` supports 2-major types of tree items. Checkable items or plain items.
    customisations.makeItemsCheckable([".doc", ".excel", "media" ]);
  }

  treeViewNodes: TreeViewItem[] = [] // Populate tree items here.
  ];
}
</script>

Output

Listening to Items Checked

To carter for advanced cases where children of the hierachical tree may be of different types. And you want to perform some further actions whenever something happens to them. You can subscribe for checked events of item types you may be interested in. And perform further actions.

Use case

E.g A school has departments, and you want to check some departments and delete them.

Solution

You can attach callbacks that notify you when departments have been checked on the tree.

How to Use

 <template>    
    <!-- Examples of how to subscribe for events -->
    <tree-view :treeViewItems="schools" @created="customiseSchools" />
</template>

 <script lang='ts'>
import { Vue, Component} from 'vue-property-decorator';

import { TreeViewCreatedEventPayload } from '@/businessLogic/contracts/types';

@Component
export default class App extends Vue {
  customiseSchools(treeCreatedEvent: TreeViewCreatedEventPayload) {
    const customisations = treeCreatedEvent.itemCustomisations;
    const eventManager = treeCreatedEvent.eventManager;

    eventManager.subscribeToItemChecked("department", (items) => console.log(items));
    customisations.makeItemsCheckable(["department"]);
  }
  schools: TreeViewItem[] = [
    {
      id: '1',
      type: 'school',
      name: 'Vue School',
      children: [
        {
          id: '2',
          type: 'department',
          name: 'Typescript Department',
          parentId: '1'
        },
        {
          id: '3',
          type: 'department',
          name: 'Open Source Department',
          parentId: '1'
        }
      ]
    }
  ]
}

Properties

Property	Default	Description
treeViewItems	Empty array	An array of TreeViewItem.
hideGuideLines	false	Determines the visibility of the guidelines
selectionMode	Multiple	Single or Multiple. This determines how many items can be simultaneously selected/checked in the tree.