Drag and Drop

The @angular/cdk/drag-drop module provides you with a way to easily and declaratively create drag-and-drop interfaces, with support for free dragging, sorting within a list, transferring items between lists, animations, touch devices, custom drag handles, previews, and placeholders, in addition to horizontal lists and locking along an axis.

link Getting started

Start by importing DragDropModule into the NgModule where you want to use drag-and-drop features. You can now add the cdkDrag directive to elements to make them draggable. When outside of a cdkDropList element, draggable elements can be freely moved around the page. You can add cdkDropList elements to constrain where elements may be dropped.

link Reordering lists

Adding cdkDropList around a set of cdkDrag elements groups the draggables into a reorderable collection. Items will automatically rearrange as an element moves. Note that this will not update your data model; you can listen to the cdkDropListDropped event to update the data model once the user finishes dragging.

link Transferring items between lists

The cdkDropList directive supports transferring dragged items between connected drop zones. You can connect one or more cdkDropList instances together by setting the cdkDropListConnectedTo property or by wrapping the elements in an element with the cdkDropListGroup attribute.

Note that cdkDropListConnectedTo works both with a direct reference to another cdkDropList, or by referencing the id of another drop container:

<!-- This is valid -->
<div cdkDropList #listOne="cdkDropList" [cdkDropListConnectedTo]="[listTwo]"></div>
<div cdkDropList #listTwo="cdkDropList" [cdkDropListConnectedTo]="[listOne]"></div>

<!-- This is valid as well -->
<div cdkDropList id="list-one" [cdkDropListConnectedTo]="['list-two']"></div>
<div cdkDropList id="list-two" [cdkDropListConnectedTo]="['list-one']"></div>

If you have an unknown number of connected drop lists, you can use the cdkDropListGroup directive to set up the connection automatically. Note that any new cdkDropList that is added under a group will be connected to all other lists automatically.

<div cdkDropListGroup>
  <!-- All lists in here will be connected. -->
  <div cdkDropList *ngFor="let list of lists"></div>
</div>

link Attaching data

You can associate some arbitrary data with both cdkDrag and cdkDropList by setting cdkDragData or cdkDropListData, respectively. Events fired from both directives include this data, allowing you to easily identify the origin of the drag or drop interaction.

<div cdkDropList [cdkDropListData]="list" *ngFor="let list of lists" (cdkDropListDropped)="drop($event)">
  <div cdkDrag [cdkDragData]="item" *ngFor="let item of list"></div>
</div>

link Styling

The cdkDrag and cdkDropList directive include only those styles strictly necessary for functionality. The application can then customize the elements by styling CSS classes added by the directives:

Selector	Description
.cdk-drop-list	Corresponds to the cdkDropList container.
.cdk-drag	Corresponds to a cdkDrag instance.
.cdk-drag-disabled	Class that is added to a disabled cdkDrag.
.cdk-drag-preview	This is the element that will be rendered next to the user's cursor as they're dragging an item in a sortable list. By default the element looks exactly like the element that is being dragged.
.cdk-drag-placeholder	This is element that will be shown instead of the real element as it's being dragged inside a cdkDropList. By default this will look exactly like the element that is being sorted.
.cdk-drop-list-dragging	A class that is added to cdkDropList while the user is dragging an item.
.cdk-drop-list-disabled	A class that is added to cdkDropList when it is disabled.
.cdk-drop-list-receiving	A class that is added to cdkDropList when it can receive an item that is being dragged inside a connected drop list.

link Animations

The drag-and-drop module supports animations both while sorting an element inside a list, as well as animating it from the position that the user dropped it to its final place in the list. To set up your animations, you have to define a transition that targets the transform property. The following classes can be used for animations:

• .cdk-drag - If you add a transition to this class, it'll animate as the user is sorting through a list.
• .cdk-drag-animating - This class is added to a cdkDrag when the user has stopped dragging. If you add a transition to it, the CDK will animate the element from its drop position to the final position inside the cdkDropList container.

Example animations:

/* Animate items as they're being sorted. */
.cdk-drop-list-dragging .cdk-drag {
  transition: transform 250ms cubic-bezier(0, 0, 0.2, 1);
}

/* Animate an item that has been dropped. */
.cdk-drag-animating {
  transition: transform 300ms cubic-bezier(0, 0, 0.2, 1);
}

link Customizing the drag area using a handle

By default, the user can drag the entire cdkDrag element to move it around. If you want to restrict the user to only be able to do so using a handle element, you can do it by adding the cdkDragHandle directive to an element inside of cdkDrag. Note that you can have as many cdkDragHandle elements as you want:

link Customizing the drag preview

When a cdkDrag element is picked up, it will create a preview element visible while dragging. By default, this will be a clone of the original element positioned next to the user's cursor. This preview can be customized, though, by providing a custom template via *cdkDragPreview. Note that the cloned element will remove its id attribute in order to avoid having multiple elements with the same id on the page. This will cause any CSS that targets that id not to be applied.

link Customizing the drag placeholder

While a cdkDrag element is being dragged, the CDK will create a placeholder element that will show where it will be placed when it's dropped. By default the placeholder is a clone of the element that is being dragged, however you can replace it with a custom one using the *cdkDragPlaceholder directive:

link List orientation

The cdkDropList directive assumes that lists are vertical by default. This can be changed by setting the orientation property to `"horizontal".

link Restricting movement within an element

If you want to stop the user from being able to drag a cdkDrag element outside of another element, you can pass a CSS selector to the cdkDragBoundary attribute. The attribute works by accepting a selector and looking up the DOM until it finds an element that matches it. If a match is found, it'll be used as the boundary outside of which the element can't be dragged. cdkDragBoundary can also be used when cdkDrag is placed inside a cdkDropList.

link Restricting movement along an axis

By default, cdkDrag allows free movement in all directions. To restrict dragging to a specific axis, you can set cdkDragLockAxis on cdkDrag or cdkDropListLockAxis on cdkDropList to either "x" or "y".

link Alternate drag root element

If there's an element that you want to make draggable, but you don't have direct access to it, you can use the cdkDragRootElement attribute. The attribute works by accepting a selector and looking up the DOM until it finds an element that matches the selector. If an element is found, it'll become the element that is moved as the user is dragging. This is useful for cases like making a dialog draggable.

link Controlling which items can be moved into a container

By default, all cdkDrag items from one container can be moved into another connected container. If you want more fine-grained control over which items can be dropped, you can use the cdkDropListEnterPredicate which will be called whenever an item is about to enter a new container. Depending on whether the predicate returns true or false, the item may or may not be allowed into the new container.

link Disable dragging

If you want to disable dragging for a particular drag item, you can do so by setting the cdkDragDisabled input on a cdkDrag item. Furthermore, you can disable an entire list using the cdkDropListDisabled input on a cdkDropList or a particular handle via cdkDragHandleDisabled on cdkDragHandle.