47 lines
2.3 KiB
Plaintext
47 lines
2.3 KiB
Plaintext
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Simple Drag and Drop Sample
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This sample demonstrates an implementation of OLE 2 drag and drop. It allows
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drag and drop operations between two instances of the sample application.
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For information on compiling and building the sample, see the makefile in
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this directory.
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Simple Drag and Drop Objects Overview :
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---------------------------------------
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Simple Drag and Drop consists of three main objects. The top level is
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CSimpleApp, under which is CSimpleDoc, and the innermost level is CSimpleSite.
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CSimpleApp is used to hold all the main window information. (eg. handle to
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the main window, handles to the main, edit, and help menus and the application
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instance) CSimpleApp always exists as long as the simple drag and drop
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application is alive.
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The next level object is CSimpleDoc object. It is instantiated when a new
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document is created. It enables and disables the menu items in the main menu.
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Since simple drag and drop is a single document interface application, the
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user is only allowed to insert one object into the document. It is
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necessary to disable certain items from the main menu to avoid incorrect
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selection. It also registers the window for drag and drop and manipulates
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the clipboard operations, such as copy to the clipboard, flush the clipboard.
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It demonstrates the implementates of two OLE interfaces in its nested classes,
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IDropSource and IDropTarget. These two interfaces are implemented as
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CDropSource and CDropTarget respectively.
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The CSimpleDoc object instantiates two different objects based on the user
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selection from the main menu. The CSimpleSite object is instantiated if the
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user chooses to insert a new object into the document. CSimpleSite
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demonstrates the implementation of IAdviseSink and IOleClientSite through its
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nested classes. These two interfaces are implemented as CAdviseSink and
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COleClientSite accordingly. CSimpleSite manipulates the storage handling and
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acts as a client site to communicate to a remote server. Such server can be
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an executable server or a dll server. The CDataXferObj object is instantiated
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when the user chooses to copy the existing object from the current document.
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it is required to copy an object to the clipboard. CDataXferObj demonstrates
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the IDataObject interface implementation and performs data transfer
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operations.
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