Angular 7 Drag and Drop – Dynamically Create Drop Zones

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After a full day of research, I found this pull request on Angular CDK repository on Github. Now, since I did not know how to integrate cdkDropListGroup into my example, I decited to create an array of IDs which will be added to [cdkDropListConnectedTo].

Each instance of my second list will have generated ID, and that ID will be added to array with suitable prefix (in my second list, on cdkDropList):

<div cdkDropList
      [attr.id]="addId(i, j)"
      [cdkDropListData]="appointment.lessons"
      [cdkDropListConnectedTo]="[subjectList]"
      (cdkDropListDropped)="drop($event)"
>

addId method:

addId(i, j) {
    this.LIST_IDS.push('cdk-drop-list-' + i + '' + j);
    return i + '' + j;
}

(cdk-drop-list- is an ID prefix. CDK places this prefix on every element with cdkDropList attribute)

So, my array will look like:

  • cdk-drop-list-00
  • cdk-drop-list-01
  • cdk-drop-list-02
  • etc.

Now, I pass that array to [cdkDropListConnectedTo] in my first list:

<div class="subj-container" 
    cdkDropListOrientation="horizontal"
    cdkDropList 
    #subjectList="cdkDropList"            
    [cdkDropListData]="subjects" 
    [cdkDropListConnectedTo]="LIST_IDS"
    (cdkDropListDropped)="drop($event)"
>

And it works flawlessly!

Hope this will help anybody with the same problem. Also, take a look at the pull request I mentioned, my solution is only a workaround, there is probably a better solution with cdkDropListGroup

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