widget/src/xpwidgets/nsTransferable.h

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  37
  38 #ifndef nsTransferable_h__
  39 #define nsTransferable_h__
  40
  41 #include "nsIFormatConverter.h"
  42 #include "nsITransferable.h"
  43 #include "nsCOMPtr.h"
  44 #include "nsString.h"
  45 #include "nsTArray.h"
  46
  47 class nsString;
  48 class nsDataObj;
  49
  50 //
  51 // DataStruct
  52 //
  53 // Holds a flavor (a mime type) that describes the data and the associated data.
  54 //
  55 struct DataStruct
  56 {
  57   DataStruct ( const char* aFlavor )
  58     : mDataLen(0), mFlavor(aFlavor), mCacheFileName(nsnull) { }
  59   ~DataStruct();
  60
  61   const nsCString& GetFlavor() const { return mFlavor; }
  62   void SetData( nsISupports* inData, PRUint32 inDataLen );
  63   void GetData( nsISupports** outData, PRUint32 *outDataLen );
  64   nsIFile * GetFileSpec(const char * aFileName);
  65   PRBool IsDataAvailable() const { return (mData && mDataLen > 0) || (!mData && mCacheFileName); }
  66
  67 protected:
  68
  69   enum {
  70     // The size of data over which we write the data to disk rather than
  71     // keep it around in memory.
  72     kLargeDatasetSize = 1000000        // 1 million bytes
  73   };
  74
  75   nsresult WriteCache(nsISupports* aData, PRUint32 aDataLen );
  76   nsresult ReadCache(nsISupports** aData, PRUint32* aDataLen );
  77
  78   nsCOMPtr<nsISupports> mData;   // OWNER - some varient of primitive wrapper
  79   PRUint32 mDataLen;
  80   const nsCString mFlavor;
  81   char *   mCacheFileName;
  82
  83 };
  84
  85 /**
  86  * XP Transferable wrapper
  87  */
  88
  89 class nsTransferable : public nsITransferable
  90 {
  91 public:
  92
  93   nsTransferable();
  94   virtual ~nsTransferable();
  95
  96     // nsISupports
  97   NS_DECL_ISUPPORTS
  98   NS_DECL_NSITRANSFERABLE
  99
 100 protected:
 101
 102     // get flavors w/out converter
 103   nsresult GetTransferDataFlavors(nsISupportsArray** aDataFlavorList);
 104
 105   nsTArray<DataStruct> mDataArray;
 106   nsCOMPtr<nsIFormatConverter> mFormatConv;
 107
 108 };
 109
 110 #endif // nsTransferable_h__