dragEnd

Type

message

Summary

Sent to the object a drag and drop started from, when the data is dropped.

Syntax

dragEnd

Description

Handle the dragEnd message to perform an action when the user drops data, or trap the message to prevent text from being deleted from a field when it's dragged to another field.

The dragEnd message is sent to the control that the drag started from. If the data is not dropped onto a control that accepts it, the dragEnd message is still sent.

LiveCode automatically handles the mechanics of dragging and dropping text between and within unlocked fields. To support this type of drag and drop operation, you don't need to do any scripting: the text is deleted from the source field automatically when LiveCode receives the dragEnd message.

To prevent the dragged text from being automatically deleted from the source field when it's dropped onto another unlocked field, trap the dragEnd message. If you don't want text from a particular field to be deleted after dragging, place a dragEnd handler in the field that does not contain a pass control structure:

    on dragEnd -- in script of field or one of its owners
        -- do nothing, but trap the message
    end dragEnd

On the other hand, if you want to perform some action when text is dragged from an unlocked field and then dropped, you need to pass the dragEnd message once you're done with it in order to allow the deletion to take place:

    on dragEnd
        set the textColor of me to \"gray\"
        pass dragEnd -- needed for text removal to occur
    end dragEnd

To make changes to the original data in a locked field or a control other than a field when a drop is completed, handle the dragEnd message. For these objects, if you want the dragged data to be removed (or changed), your dragEnd handler must delete the dragged text from the source object (or perform whatever action you want to do on a drop); the behavior is not automated as it is for unlocked fields.

Examples

on dragEnd -- remove data being dragged
  delete the dragSource
end dragEnd

Related

glossary: object, handler, message, unlock, control structure, drag and drop, control, trap

keyword: field

message: dragEnd, dragDrop, mouseRelease

object: field

property: dragImage, acceptDrop

control structure: pass

function: dragSource, dragDestination

Compatibility and Support

Introduced

LiveCode 2.0

OS

mac

windows

linux

Platforms

desktop

server