Mozilla/mozilla/widget/src/xpwidgets/nsTransferable.cpp
rods%netscape.com 7029d76ae1 Updated some comments/documentation
git-svn-id: svn://10.0.0.236/trunk@28048 18797224-902f-48f8-a5cc-f745e15eee43
1999-04-19 19:02:52 +00:00

350 lines
9.0 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
*
* The contents of this file are subject to the Netscape Public License
* Version 1.0 (the "NPL"); you may not use this file except in
* compliance with the NPL. You may obtain a copy of the NPL at
* http://www.mozilla.org/NPL/
*
* Software distributed under the NPL is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL
* for the specific language governing rights and limitations under the
* NPL.
*
* The Initial Developer of this code under the NPL is Netscape
* Communications Corporation. Portions created by Netscape are
* Copyright (C) 1998 Netscape Communications Corporation. All Rights
* Reserved.
*/
#include "nsTransferable.h"
#include "nsIDataFlavor.h"
#include "nsDataFlavor.h"
#include "nsWidgetsCID.h"
#include "nsISupportsArray.h"
#include "nsIFormatConverter.h"
#include "nsVoidArray.h"
#include "nsIComponentManager.h"
#include "nsCOMPtr.h"
static NS_DEFINE_IID(kITransferableIID, NS_ITRANSFERABLE_IID);
static NS_DEFINE_IID(kIGenericTransferableIID, NS_IGENERICTRANSFERABLE_IID);
static NS_DEFINE_IID(kIDataFlavorIID, NS_IDATAFLAVOR_IID);
static NS_DEFINE_IID(kCDataFlavorCID, NS_DATAFLAVOR_CID);
NS_IMPL_ADDREF(nsTransferable)
NS_IMPL_RELEASE(nsTransferable)
typedef struct {
nsIDataFlavor * mFlavor;
char * mData;
PRUint32 mDataLen;
} DataStruct;
//-------------------------------------------------------------------------
//
// Transferable constructor
//
//-------------------------------------------------------------------------
nsTransferable::nsTransferable()
{
NS_INIT_REFCNT();
mDataArray = new nsVoidArray();
}
//-------------------------------------------------------------------------
//
// Transferable destructor
//
//-------------------------------------------------------------------------
nsTransferable::~nsTransferable()
{
PRInt32 i;
for (i=0;i<mDataArray->Count();i++) {
DataStruct * data = (DataStruct *)mDataArray->ElementAt(i);
NS_RELEASE(data->mFlavor);
if (data->mData) {
delete[] data->mData;
}
}
delete mDataArray;
}
/**
* @param aIID The name of the class implementing the method
* @param _classiiddef The name of the #define symbol that defines the IID
* for the class (e.g. NS_ISUPPORTS_IID)
*
*/
nsresult nsTransferable::QueryInterface(const nsIID& aIID, void** aInstancePtr)
{
if (NULL == aInstancePtr) {
return NS_ERROR_NULL_POINTER;
}
nsresult rv = NS_NOINTERFACE;
if (aIID.Equals(kITransferableIID)) {
*aInstancePtr = (void*) ((nsITransferable*)this);
NS_ADDREF_THIS();
return NS_OK;
}
if (aIID.Equals(kIGenericTransferableIID)) {
*aInstancePtr = (void*) ((nsIGenericTransferable*)this);
NS_ADDREF_THIS();
return NS_OK;
}
return rv;
}
/**
*
*
*/
NS_IMETHODIMP nsTransferable::GetTransferDataFlavors(nsISupportsArray ** aDataFlavorList)
{
nsISupportsArray * array;
nsresult rv = NS_NewISupportsArray(&array);
if (NS_OK == rv) {
PRInt32 i;
for (i=0;i<mDataArray->Count();i++) {
DataStruct * data = (DataStruct *)mDataArray->ElementAt(i);
array->AppendElement(data->mFlavor); // this addref's for us
}
*aDataFlavorList = array;
}
return NS_OK;
}
/**
*
*
*/
NS_IMETHODIMP nsTransferable::IsDataFlavorSupported(nsIDataFlavor * aDataFlavor)
{
nsAutoString mimeInQuestion;
aDataFlavor->GetMimeType(mimeInQuestion);
PRInt32 i;
for (i=0;i<mDataArray->Count();i++) {
DataStruct * data = (DataStruct *)mDataArray->ElementAt(i);
nsAutoString mime;
data->mFlavor->GetMimeType(mime);
if (mimeInQuestion.Equals(mime)) {
return NS_OK;
}
}
return NS_ERROR_FAILURE;
}
/**
* The transferable owns the data (memory) and only gives the aData a copy of the pointer address to it.
*
*/
NS_IMETHODIMP nsTransferable::GetTransferData(nsIDataFlavor * aDataFlavor, void ** aData, PRUint32 * aDataLen)
{
nsAutoString mimeInQuestion;
aDataFlavor->GetMimeType(mimeInQuestion);
PRInt32 i;
for (i=0;i<mDataArray->Count();i++) {
DataStruct * data = (DataStruct *)mDataArray->ElementAt(i);
nsAutoString mime;
data->mFlavor->GetMimeType(mime);
if (mimeInQuestion.Equals(mime)) {
*aData = data->mData;
*aDataLen = data->mDataLen;
return NS_OK;
}
}
if ( mFormatConv ) {
for (i=0;i<mDataArray->Count();i++) {
DataStruct * data = (DataStruct *)mDataArray->ElementAt(i);
if (NS_OK == mFormatConv->CanConvert(data->mFlavor, aDataFlavor)) {
mFormatConv->Convert(data->mFlavor, data->mData, data->mDataLen, aDataFlavor, aData, aDataLen);
return NS_OK;
}
}
}
return NS_ERROR_FAILURE;
}
/**
* The transferable now owns the data (the memory pointing to it)
*
*/
NS_IMETHODIMP nsTransferable::SetTransferData(nsIDataFlavor * aDataFlavor, void * aData, PRUint32 aDataLen)
{
if (aData == nsnull) {
return NS_ERROR_FAILURE;
}
nsAutoString mimeInQuestion;
aDataFlavor->GetMimeType(mimeInQuestion);
PRInt32 i;
for (i=0;i<mDataArray->Count();i++) {
DataStruct * data = (DataStruct *)mDataArray->ElementAt(i);
nsAutoString mime;
data->mFlavor->GetMimeType(mime);
if (mimeInQuestion.Equals(mime)) {
if (nsnull != data->mData) {
delete[] data->mData;
}
data->mData = (char *)aData;
data->mDataLen = aDataLen;
return NS_OK;
}
}
return NS_OK;
}
/**
*
*
*/
NS_IMETHODIMP nsTransferable::AddDataFlavor(nsIDataFlavor * aDataFlavor)
{
if (nsnull == aDataFlavor) {
return NS_ERROR_FAILURE;
}
nsAutoString mimeInQuestion;
aDataFlavor->GetMimeType(mimeInQuestion);
// Do we have the data flavor already?
PRInt32 i;
for (i=0;i<mDataArray->Count();i++) {
DataStruct * data = (DataStruct *)mDataArray->ElementAt(i);
nsAutoString mime;
data->mFlavor->GetMimeType(mime);
if (mimeInQuestion.Equals(mime)) {
return NS_ERROR_FAILURE;
}
}
// Create a new "slot" for the data
DataStruct * data = new DataStruct;
data->mFlavor = aDataFlavor;
data->mData = nsnull;
data->mDataLen = 0;
NS_ADDREF(aDataFlavor);
mDataArray->AppendElement((void *)data);
return NS_OK;
}
/**
*
*
*/
NS_IMETHODIMP_(PRBool) nsTransferable::IsLargeDataSet()
{
return PR_FALSE;
}
/**
*
*
*/
NS_IMETHODIMP nsTransferable::SetConverter(nsIFormatConverter * aConverter)
{
mFormatConv = dont_QueryInterface(aConverter);
return NS_OK;
}
/**
*
*
*/
NS_IMETHODIMP nsTransferable::GetConverter(nsIFormatConverter ** aConverter)
{
if ( mFormatConv ) {
*aConverter = mFormatConv;
NS_ADDREF(*aConverter);
} else {
*aConverter = nsnull;
}
return NS_OK;
}
//
// FlavorsTransferableCanImport
//
// Computes a list of flavors that the transferable can accept into it, either through
// intrinsic knowledge or input data converters.
//
NS_IMETHODIMP
nsTransferable :: FlavorsTransferableCanImport ( nsISupportsArray** outFlavorList )
{
if ( !outFlavorList )
return NS_ERROR_INVALID_ARG;
// Get the flavor list, and on to the end of it, append the list of flavors we
// can also get to through a converter. This is so that we can just walk the list
// in one go, looking for the desired flavor.
GetTransferDataFlavors(outFlavorList); // addrefs
nsCOMPtr<nsIFormatConverter> converter;
GetConverter(getter_AddRefs(converter));
if ( converter ) {
nsCOMPtr<nsISupportsArray> convertedList;
converter->GetInputDataFlavors(getter_AddRefs(convertedList));
if ( convertedList ) {
PRUint32 i;
for (i=0;i<convertedList->Count();i++) {
nsCOMPtr<nsISupports> temp = getter_AddRefs(convertedList->ElementAt(i));
(*outFlavorList)->AppendElement(temp); // this addref's for us
} // foreach flavor that can be converted to
}
} // if a converter exists
return NS_OK;
} // FlavorsTransferableCanImport
//
// FlavorsTransferableCanExport
//
// Computes a list of flavors that the transferable can export, either through
// intrinsic knowledge or output data converters.
//
NS_IMETHODIMP
nsTransferable :: FlavorsTransferableCanExport ( nsISupportsArray** outFlavorList )
{
if ( !outFlavorList )
return NS_ERROR_INVALID_ARG;
// Get the flavor list, and on to the end of it, append the list of flavors we
// can also get to through a converter. This is so that we can just walk the list
// in one go, looking for the desired flavor.
GetTransferDataFlavors(outFlavorList); // addrefs
nsCOMPtr<nsIFormatConverter> converter;
GetConverter(getter_AddRefs(converter));
if ( converter ) {
nsCOMPtr<nsISupportsArray> convertedList;
converter->GetOutputDataFlavors(getter_AddRefs(convertedList));
if ( convertedList ) {
PRUint32 i;
for (i=0;i<convertedList->Count();i++) {
nsCOMPtr<nsISupports> temp = getter_AddRefs(convertedList->ElementAt(i));
(*outFlavorList)->AppendElement(temp); // this addref's for us
} // foreach flavor that can be converted to
}
} // if a converter exists
return NS_OK;
} // FlavorsTransferableCanImport