\n#include <wrl\/client.h>\n#include <wrl\/event.h>\n#include <wrl\/wrappers\/corewrappers.h>\n#include <windows.applicationmodel.datatransfer.h>\n#include <shlobj.h> \/\/ IDataTransferManagerInterop\n#include <tchar.h> \/\/ Huh? Why are you still using ANSI?\n#include <roapi.h>\n\nnamespace WRL = Microsoft::WRL;\nnamespace awf = ABI::Windows::Foundation;\nnamespace dt = ABI::Windows::ApplicationModel::DataTransfer;\n\nusing Microsoft::WRL::Wrappers::HStringReference;\n\nWRL::ComPtr<IDataTransferManagerInterop> g_dtmInterop;\nWRL::ComPtr<DT::IDataTransferManager> g_dtm;\nEventRegistrationToken g_dataRequestedToken;\n<\/pre>\nNote that in real life, these global variables would be instance variables of some C++ class. <\/p>\n
\nBOOL\nOnCreate(HWND hwnd, LPCREATESTRUCT lpcs)\n{\n RoGetActivationFactory(HStringReference(\n RuntimeClass_Windows_ApplicationModel_DataTransfer_DataTransferManager)\n .Get(), IID_PPV_ARGS(&g_dtmInterop));\n\n g_dtmInterop->GetForWindow(hwnd, IID_PPV_ARGS(&g_dtm));\n\n auto callback = WRL::Callback<WF::ITypedEventHandler<\n DT::DataTransferManager*, DT::DataRequestedEventArgs*>>(\n [](auto&&, DT::IDataRequestedEventArgs* e)\n {\n WRL::ComPtr<DT::IDataRequest> request;\n e->get_Request(&request);\n\n WRL::ComPtr<DT::IDataPackage> data;\n request->get_Data(&data);\n\n WRL::ComPtr<DT::IDataPackagePropertySet> properties;\n data->get_Properties(&properties);\n\n \/\/ Title is mandatory\n properties->put_Title(HStringReference(L\"Title from Win32\").Get());\n\n \/\/ Description is optional\n properties->put_Description(HStringReference(L\"This text came from a Win32 app\").Get());\n\n data->SetText(HStringReference(L\"Text from Win32 app!\").Get());\n\n return S_OK;\n });\n\n g_dtm->add_DataRequested(callback.Get(), &g_dataRequestedToken);\n\n return TRUE;\n}\n\nvoid\nOnDestroy(HWND hwnd)\n{\n g_dtm->remove_DataRequested(g_dataRequestedToken);\n g_dtm.Reset();\n g_dtmInterop.Reset();\n PostQuitMessage(0);\n}\n\n\nvoid OnChar(HWND hwnd, TCHAR ch, int cRepeat)\n{\n switch (ch) {\n case TEXT(' '):\n g_dtmInterop->ShowShareUIForWindow(hwnd);\n }\n break;\n }\n}\n\nHANDLE_MSG(hwnd, WM_CHAR, OnChar);\n<\/pre>\nOkay, let’s see what happened here. <\/p>\n
When the window is created, we get the interop interface and save it in the global variable for later use. We then call GetForWindow<\/code> to obtain the DataTransferManager<\/code> for our window. In WinRT this would have been a call to GetForCurrentView<\/code>. <\/p>\nThat’s all for the interop part of this exercise. Everything else is just operating on the WinRT objects at the ABI level instead of at the projection level. <\/p>\n
Next we create a callback handler for the DataRequested<\/code> event. We’ll look at the body of the handler later. <\/p>\nWe then register the handler for the event by calling add_DataRequested<\/code> and save the registration token so we can unregister later. <\/p>\nOkay, now to look inside the callback: This is a direct translation of DataTransferManager<\/code> from projection back into ABI. Reading a property becomes a call to the get_PropertyName<\/code> method, and writing a property becomes a call to the put_PropertyName<\/code> method. In our case, we take the DataRequestedEventArgs<\/code> and get the Request<\/code> property, which is an IDataRequest<\/code>. From the IDataRequest<\/code> we set the Title<\/code> and Description<\/code> properties, and use the SetText<\/code> method to provide the text that we are sharing. <\/p>\nAt destruction, we unregister the event and release the objects. <\/p>\n
The final snippet of code is what we saw last time: When the user hits the space bar, open the share pane. But this time, the share pane actually shows something interesting, because our DataRequested<\/code> event handler provides text to be shared. <\/p>\nOf course, in a real program, you would presumably offer text or other content that is based on the current state or selection rather than just spitting out hard-coded content, but this is just a Little Program. <\/p>\n","protected":false},"excerpt":{"rendered":"
Continuing the interop pattern.<\/p>\n","protected":false},"author":1069,"featured_media":111744,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[1],"tags":[25],"class_list":["post-95745","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-oldnewthing","tag-code"],"acf":[],"blog_post_summary":"
Continuing the interop pattern.<\/p>\n","_links":{"self":[{"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/posts\/95745","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/users\/1069"}],"replies":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/comments?post=95745"}],"version-history":[{"count":0,"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/posts\/95745\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/media\/111744"}],"wp:attachment":[{"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/media?parent=95745"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/categories?post=95745"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/tags?post=95745"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}