.. index:: pair: class; EE::Window::DragAndDrop
.. _doxid-class_e_e_1_1_window_1_1_drag_and_drop:

class EE::Window::DragAndDrop
=============================

.. toctree::
	:hidden:

Overview
~~~~~~~~

Native cross-application file dragging. :ref:`More...<details-class_e_e_1_1_window_1_1_drag_and_drop>`


.. ref-code-block:: cpp
	:class: doxyrest-overview-code-block

	#include <draganddrop.hpp>
	
	class DragAndDrop {
	public:
		// methods
	
		static DragAndDrop :target:`forWindow<doxid-class_e_e_1_1_window_1_1_drag_and_drop_1a62ed133cf18a0035beb3532bcfd90177>`(:ref:`Window<doxid-class_e_e_1_1_window_1_1_window>`& window);
		static bool :ref:`encodeFileUriList<doxid-class_e_e_1_1_window_1_1_drag_and_drop_1a4837260c7874093f66402105ff93d58b>`(const :ref:`DragOffer<doxid-struct_e_e_1_1_window_1_1_drag_offer>`& offer, std::string& output, std::string* error = nullptr);
		:ref:`DragCapabilities<doxid-struct_e_e_1_1_window_1_1_drag_capabilities>` :target:`getCapabilities<doxid-class_e_e_1_1_window_1_1_drag_and_drop_1adc4e6f46ad5cd711e4b19ce62ab50740>`() const;
		:ref:`DragStartResult<doxid-struct_e_e_1_1_window_1_1_drag_start_result>` :ref:`startDrag<doxid-class_e_e_1_1_window_1_1_drag_and_drop_1a4726f8947be89013401216888a5ee727>`(const :ref:`DragOffer<doxid-struct_e_e_1_1_window_1_1_drag_offer>`& offer, :ref:`DragCompletionCallback<doxid-namespace_e_e_1_1_window_1a222dc4cbe0f55e56b2731d7823f4d772>` completion = {});
		void :target:`cancelDrag<doxid-class_e_e_1_1_window_1_1_drag_and_drop_1a25664cf5b765c4ec7d1aedb05232e730>`();
		bool :target:`isDragging<doxid-class_e_e_1_1_window_1_1_drag_and_drop_1ab954ea927fe41585ea3f3379ec79dade>`() const;
		bool :ref:`setDataDropHandler<doxid-class_e_e_1_1_window_1_1_drag_and_drop_1a9d684726565233a84fb04ef99767348e>`(std::vector<std::string> mimeTypes, :ref:`DataDropCallback<doxid-namespace_e_e_1_1_window_1a06200a6910d8986d1afd7f5dbfa1cf0a>` callback);
		bool :ref:`setFileSaveDropHandler<doxid-class_e_e_1_1_window_1_1_drag_and_drop_1a07e90b9e2961e7a9cd1a939a163f224b>`(:ref:`FileSaveDropCallback<doxid-namespace_e_e_1_1_window_1a8f7f15deff536148ec374d627f7c8583>` callback);
	};
.. _details-class_e_e_1_1_window_1_1_drag_and_drop:

Detailed Documentation
~~~~~~~~~~~~~~~~~~~~~~

Native cross-application file dragging. All methods must run on the window/UI thread. This lightweight facade borrows its :ref:`Window <doxid-class_e_e_1_1_window_1_1_window>` and must not outlive it. A started session owns its serialized payload and completion callback. Rejected starts never invoke completion. Completions run once, outside native event hooks, when input is updated; they may start another drag. Cancellation/closing a source window also completes the session. Callbacks must not borrow objects that may be destroyed before completion (use weak ownership when appropriate). :ref:`Engine <doxid-class_e_e_1_1_window_1_1_engine>` teardown cancels and releases pending sessions without invoking their callbacks. Initially only Copy is supported. Dropped means the native transfer finished, not that a browser uploaded or a file manager copied a file. Existing internal :ref:`UI <doxid-namespace_e_e_1_1_u_i>` dragging is independent.

Methods
-------

.. index:: pair: function; encodeFileUriList
.. _doxid-class_e_e_1_1_window_1_1_drag_and_drop_1a4837260c7874093f66402105ff93d58b:

.. ref-code-block:: cpp
	:class: doxyrest-title-code-block

	static bool encodeFileUriList(const :ref:`DragOffer<doxid-struct_e_e_1_1_window_1_1_drag_offer>`& offer, std::string& output, std::string* error = nullptr)

Serialize an offer as text/uri-list (CRLF). Rejects empty, relative, invalid UTF-8 and NUL paths. Preserves order and duplicate entries. On failure output is empty.

.. index:: pair: function; startDrag
.. _doxid-class_e_e_1_1_window_1_1_drag_and_drop_1a4726f8947be89013401216888a5ee727:

.. ref-code-block:: cpp
	:class: doxyrest-title-code-block

	:ref:`DragStartResult<doxid-struct_e_e_1_1_window_1_1_drag_start_result>` startDrag(const :ref:`DragOffer<doxid-struct_e_e_1_1_window_1_1_drag_offer>`& offer, :ref:`DragCompletionCallback<doxid-namespace_e_e_1_1_window_1a222dc4cbe0f55e56b2731d7823f4d772>` completion = {})

Call after a movement threshold, while the initiating left mouse button is still down. Preview images must be RGB/RGBA, at most 2048 pixels per side and 1,048,576 pixels total. The offer is read synchronously; the session retains only its own native representation.

.. index:: pair: function; setDataDropHandler
.. _doxid-class_e_e_1_1_window_1_1_drag_and_drop_1a9d684726565233a84fb04ef99767348e:

.. ref-code-block:: cpp
	:class: doxyrest-title-code-block

	bool setDataDropHandler(std::vector<std::string> mimeTypes, :ref:`DataDropCallback<doxid-namespace_e_e_1_1_window_1a06200a6910d8986d1afd7f5dbfa1cf0a>` callback)

Receive drags from other applications that offer one of mimeTypes and no file list (text/uri-list), such as an archive manager's extraction protocol. Drags with a file list keep arriving as FileDropped events. The callback runs on the :ref:`UI <doxid-namespace_e_e_1_1_u_i>` thread, outside native event hooks, after the source was told the drop succeeded. Replaces this window's previous handler; an empty list removes it. Returns false where unsupported (see dataTarget).

.. index:: pair: function; setFileSaveDropHandler
.. _doxid-class_e_e_1_1_window_1_1_drag_and_drop_1a07e90b9e2961e7a9cd1a939a163f224b:

.. ref-code-block:: cpp
	:class: doxyrest-title-code-block

	bool setFileSaveDropHandler(:ref:`FileSaveDropCallback<doxid-namespace_e_e_1_1_window_1a8f7f15deff536148ec374d627f7c8583>` callback)

Receive drags from other applications whose source saves the file where it is dropped (XDS). These take priority over a file list offered with them, which such sources only fill with temporary copies, if at all. The callback runs on the :ref:`UI <doxid-namespace_e_e_1_1_u_i>` thread, outside native event hooks, when the drag is dropped; the source then saves into the returned folder. Replaces this window's previous handler; an empty callback removes it. Returns false where unsupported (see dataTarget).