juicysfplugin/modules/juce_gui_basics/native/juce_win32_DragAndDrop.cpp

355 lines
11 KiB
C++

/*
==============================================================================
This file is part of the JUCE library.
Copyright (c) 2017 - ROLI Ltd.
JUCE is an open source library subject to commercial or open-source
licensing.
By using JUCE, you agree to the terms of both the JUCE 5 End-User License
Agreement and JUCE 5 Privacy Policy (both updated and effective as of the
27th April 2017).
End User License Agreement: www.juce.com/juce-5-licence
Privacy Policy: www.juce.com/juce-5-privacy-policy
Or: You may also use this code under the terms of the GPL v3 (see
www.gnu.org/licenses).
JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
DISCLAIMED.
==============================================================================
*/
namespace juce
{
namespace DragAndDropHelpers
{
//==============================================================================
struct JuceDropSource : public ComBaseClassHelper<IDropSource>
{
JuceDropSource() {}
JUCE_COMRESULT QueryContinueDrag (BOOL escapePressed, DWORD keys) override
{
if (escapePressed)
return DRAGDROP_S_CANCEL;
if ((keys & (MK_LBUTTON | MK_RBUTTON)) == 0)
return DRAGDROP_S_DROP;
return S_OK;
}
JUCE_COMRESULT GiveFeedback (DWORD) override
{
return DRAGDROP_S_USEDEFAULTCURSORS;
}
};
//==============================================================================
struct JuceEnumFormatEtc : public ComBaseClassHelper<IEnumFORMATETC>
{
JuceEnumFormatEtc (const FORMATETC* f) : format (f) {}
JUCE_COMRESULT Clone (IEnumFORMATETC** result) override
{
if (result == 0)
return E_POINTER;
auto newOne = new JuceEnumFormatEtc (format);
newOne->index = index;
*result = newOne;
return S_OK;
}
JUCE_COMRESULT Next (ULONG celt, LPFORMATETC lpFormatEtc, ULONG* pceltFetched) override
{
if (pceltFetched != nullptr)
*pceltFetched = 0;
else if (celt != 1)
return S_FALSE;
if (index == 0 && celt > 0 && lpFormatEtc != 0)
{
copyFormatEtc (lpFormatEtc [0], *format);
++index;
if (pceltFetched != nullptr)
*pceltFetched = 1;
return S_OK;
}
return S_FALSE;
}
JUCE_COMRESULT Skip (ULONG celt) override
{
if (index + (int) celt >= 1)
return S_FALSE;
index += celt;
return S_OK;
}
JUCE_COMRESULT Reset() override
{
index = 0;
return S_OK;
}
private:
const FORMATETC* const format;
int index = 0;
static void copyFormatEtc (FORMATETC& dest, const FORMATETC& source)
{
dest = source;
if (source.ptd != 0)
{
dest.ptd = (DVTARGETDEVICE*) CoTaskMemAlloc (sizeof (DVTARGETDEVICE));
*(dest.ptd) = *(source.ptd);
}
}
JUCE_DECLARE_NON_COPYABLE (JuceEnumFormatEtc)
};
//==============================================================================
class JuceDataObject : public ComBaseClassHelper <IDataObject>
{
public:
JuceDataObject (JuceDropSource* s, const FORMATETC* f, const STGMEDIUM* m)
: dropSource (s), format (f), medium (m)
{
}
~JuceDataObject()
{
jassert (refCount == 0);
}
JUCE_COMRESULT GetData (FORMATETC* pFormatEtc, STGMEDIUM* pMedium)
{
if ((pFormatEtc->tymed & format->tymed) != 0
&& pFormatEtc->cfFormat == format->cfFormat
&& pFormatEtc->dwAspect == format->dwAspect)
{
pMedium->tymed = format->tymed;
pMedium->pUnkForRelease = 0;
if (format->tymed == TYMED_HGLOBAL)
{
auto len = GlobalSize (medium->hGlobal);
void* const src = GlobalLock (medium->hGlobal);
void* const dst = GlobalAlloc (GMEM_FIXED, len);
memcpy (dst, src, len);
GlobalUnlock (medium->hGlobal);
pMedium->hGlobal = dst;
return S_OK;
}
}
return DV_E_FORMATETC;
}
JUCE_COMRESULT QueryGetData (FORMATETC* f)
{
if (f == 0)
return E_INVALIDARG;
if (f->tymed == format->tymed
&& f->cfFormat == format->cfFormat
&& f->dwAspect == format->dwAspect)
return S_OK;
return DV_E_FORMATETC;
}
JUCE_COMRESULT GetCanonicalFormatEtc (FORMATETC*, FORMATETC* pFormatEtcOut)
{
pFormatEtcOut->ptd = 0;
return E_NOTIMPL;
}
JUCE_COMRESULT EnumFormatEtc (DWORD direction, IEnumFORMATETC** result)
{
if (result == 0)
return E_POINTER;
if (direction == DATADIR_GET)
{
*result = new JuceEnumFormatEtc (format);
return S_OK;
}
*result = 0;
return E_NOTIMPL;
}
JUCE_COMRESULT GetDataHere (FORMATETC*, STGMEDIUM*) { return DATA_E_FORMATETC; }
JUCE_COMRESULT SetData (FORMATETC*, STGMEDIUM*, BOOL) { return E_NOTIMPL; }
JUCE_COMRESULT DAdvise (FORMATETC*, DWORD, IAdviseSink*, DWORD*) { return OLE_E_ADVISENOTSUPPORTED; }
JUCE_COMRESULT DUnadvise (DWORD) { return E_NOTIMPL; }
JUCE_COMRESULT EnumDAdvise (IEnumSTATDATA**) { return OLE_E_ADVISENOTSUPPORTED; }
private:
JuceDropSource* const dropSource;
const FORMATETC* const format;
const STGMEDIUM* const medium;
JUCE_DECLARE_NON_COPYABLE (JuceDataObject)
};
//==============================================================================
HDROP createHDrop (const StringArray& fileNames)
{
int totalBytes = 0;
for (int i = fileNames.size(); --i >= 0;)
totalBytes += (int) CharPointer_UTF16::getBytesRequiredFor (fileNames[i].getCharPointer()) + sizeof (WCHAR);
HDROP hDrop = (HDROP) GlobalAlloc (GMEM_MOVEABLE | GMEM_ZEROINIT, sizeof (DROPFILES) + totalBytes + 4);
if (hDrop != 0)
{
auto pDropFiles = (LPDROPFILES) GlobalLock (hDrop);
pDropFiles->pFiles = sizeof (DROPFILES);
pDropFiles->fWide = true;
auto* fname = reinterpret_cast<WCHAR*> (addBytesToPointer (pDropFiles, sizeof (DROPFILES)));
for (int i = 0; i < fileNames.size(); ++i)
{
auto bytesWritten = fileNames[i].copyToUTF16 (fname, 2048);
fname = reinterpret_cast<WCHAR*> (addBytesToPointer (fname, bytesWritten));
}
*fname = 0;
GlobalUnlock (hDrop);
}
return hDrop;
}
struct DragAndDropJob : public ThreadPoolJob
{
DragAndDropJob (FORMATETC f, STGMEDIUM m, DWORD d, std::function<void()> cb)
: ThreadPoolJob ("DragAndDrop"),
format (f), medium (m), whatToDo (d),
completionCallback (cb)
{
}
JobStatus runJob() override
{
OleInitialize (0);
auto source = new JuceDropSource();
auto data = new JuceDataObject (source, &format, &medium);
DWORD effect;
DoDragDrop (data, source, whatToDo, &effect);
data->Release();
source->Release();
OleUninitialize();
if (completionCallback != nullptr)
MessageManager::callAsync (completionCallback);
return jobHasFinished;
}
FORMATETC format;
STGMEDIUM medium;
DWORD whatToDo;
std::function<void()> completionCallback;
};
class ThreadPoolHolder : private DeletedAtShutdown
{
public:
ThreadPoolHolder() = default;
~ThreadPoolHolder()
{
// Wait forever if there's a job running. The user needs to cancel the transfer
// in the GUI.
pool.removeAllJobs (true, -1);
clearSingletonInstance();
}
JUCE_DECLARE_SINGLETON_SINGLETHREADED (ThreadPoolHolder, false)
// We need to make sure we don't do simultaneous text and file drag and drops,
// so use a pool that can only run a single job.
ThreadPool pool { 1 };
};
JUCE_IMPLEMENT_SINGLETON (ThreadPoolHolder)
}
//==============================================================================
bool DragAndDropContainer::performExternalDragDropOfFiles (const StringArray& files, const bool canMove,
Component*, std::function<void()> callback)
{
if (files.isEmpty())
return false;
FORMATETC format = { CF_HDROP, 0, DVASPECT_CONTENT, -1, TYMED_HGLOBAL };
STGMEDIUM medium = { TYMED_HGLOBAL, { 0 }, 0 };
medium.hGlobal = DragAndDropHelpers::createHDrop (files);
auto& pool = DragAndDropHelpers::ThreadPoolHolder::getInstance()->pool;
pool.addJob (new DragAndDropHelpers::DragAndDropJob (format, medium,
canMove ? (DROPEFFECT_COPY | DROPEFFECT_MOVE) : DROPEFFECT_COPY,
callback),
true);
return true;
}
bool DragAndDropContainer::performExternalDragDropOfText (const String& text, Component*, std::function<void()> callback)
{
if (text.isEmpty())
return false;
FORMATETC format = { CF_TEXT, 0, DVASPECT_CONTENT, -1, TYMED_HGLOBAL };
STGMEDIUM medium = { TYMED_HGLOBAL, { 0 }, 0 };
auto numBytes = CharPointer_UTF16::getBytesRequiredFor (text.getCharPointer());
medium.hGlobal = GlobalAlloc (GMEM_MOVEABLE | GMEM_ZEROINIT, numBytes + 2);
auto* data = static_cast<WCHAR*> (GlobalLock (medium.hGlobal));
text.copyToUTF16 (data, numBytes + 2);
format.cfFormat = CF_UNICODETEXT;
GlobalUnlock (medium.hGlobal);
auto& pool = DragAndDropHelpers::ThreadPoolHolder::getInstance()->pool;
pool.addJob (new DragAndDropHelpers::DragAndDropJob (format,
medium,
DROPEFFECT_COPY | DROPEFFECT_MOVE,
callback),
true);
return true;
}
} // namespace juce