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CEF4Delphi/source/uCEFDragAndDropMgr.pas
Salvador Diaz Fau 83cf65a8ec Workaround for issue #333
Disabled range checking in some units when using old Delphi versions to avoid internal compiler errors.
2021-01-05 11:44:41 +01:00

834 lines
30 KiB
ObjectPascal

// ************************************************************************
// ***************************** CEF4Delphi *******************************
// ************************************************************************
//
// CEF4Delphi is based on DCEF3 which uses CEF to embed a chromium-based
// browser in Delphi applications.
//
// The original license of DCEF3 still applies to CEF4Delphi.
//
// For more information about CEF4Delphi visit :
// https://www.briskbard.com/index.php?lang=en&pageid=cef
//
// Copyright © 2021 Salvador Diaz Fau. All rights reserved.
//
// ************************************************************************
// ************ vvvv Original license and comments below vvvv *************
// ************************************************************************
(*
* Delphi Chromium Embedded 3
*
* Usage allowed under the restrictions of the Lesser GNU General Public License
* or alternatively the restrictions of the Mozilla Public License 1.1
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for
* the specific language governing rights and limitations under the License.
*
* Unit owner : Henri Gourvest <hgourvest@gmail.com>
* Web site : http://www.progdigy.com
* Repository : http://code.google.com/p/delphichromiumembedded/
* Group : http://groups.google.com/group/delphichromiumembedded
*
* Embarcadero Technologies, Inc is not permitted to use or redistribute
* this source code without explicit permission.
*
*)
unit uCEFDragAndDropMgr;
{$IFDEF FPC}
{$MODE OBJFPC}{$H+}
{$ENDIF}
{$I cef.inc}
{$IFNDEF FPC}{$IFNDEF DELPHI12_UP}
// Workaround for "Internal error" in old Delphi versions caused by uint64 handling
{$R-}
{$ENDIF}{$ENDIF}
interface
uses
{$IFDEF DELPHI16_UP}
{$IFDEF MSWINDOWS}WinApi.Windows, WinApi.ActiveX, WinApi.ShlObj, WinApi.ShellApi,{$ENDIF}
System.Classes, System.SysUtils, System.Math, System.StrUtils, System.AnsiStrings,
{$ELSE}
{$IFDEF MSWINDOWS}Windows, ActiveX, ShlObj, Shellapi,{$ENDIF}
Classes, SysUtils, Math, StrUtils, {$IFDEF DELPHI12_UP}AnsiStrings,{$ENDIF}
{$ENDIF}
uCEFDragData, uCEFInterfaces, uCEFTypes, uCEFOLEDragAndDrop;
type
TDragEnterEvent = procedure(Sender: TObject; const aDragData : ICefDragData; grfKeyState: Longint; pt: TPoint; var dwEffect: Longint) of object;
TDragOverEvent = procedure(Sender: TObject; grfKeyState: Longint; pt: TPoint; var dwEffect: Longint) of object;
TDropEvent = procedure(Sender: TObject; grfKeyState: Longint; pt: TPoint; var dwEffect: Longint) of object;
TCEFDragAndDropMgr = class(TOLEDragAndDropMgr)
protected
FCurrentDragData : ICefDragData;
FOLEEffect : integer;
FMozURLFormat : cardinal;
FHTMLFormat : cardinal;
FFileDescFormat : cardinal;
FFileContentsFormat : cardinal;
FOnDragEnter : TDragEnterEvent;
FOnDragOver : TDragOverEvent;
FOnDragLeave : TNotifyEvent;
FOnDrop : TDropEvent;
function DragDataToDataObject_Unicode(const aDragData : ICefDragData; var aFormat : TFormatEtc; var aMedium : TStgMedium) : boolean;
function DragDataToDataObject_Text(const aDragData : ICefDragData; var aFormat : TFormatEtc; var aMedium : TStgMedium) : boolean;
function DragDataToDataObject_HTML(const aDragData : ICefDragData; var aFormat : TFormatEtc; var aMedium : TStgMedium) : boolean;
function DragDataToDataObject_URL(const aDragData : ICefDragData; var aFormat : TFormatEtc; var aMedium : TStgMedium) : boolean;
function DragDataToDataObject_FileDesc(const aDragData : ICefDragData; var aFormat : TFormatEtc; var aMedium : TStgMedium) : boolean;
function DragDataToDataObject_FileContents(const aDragData : ICefDragData; var aFormat : TFormatEtc; var aMedium : TStgMedium) : boolean;
procedure DataObjectToDragData(const aDataObject : IDataObject; var aDragData : ICefDragData);
function DataObjectToDragData_Unicode(var aMedium : TStgMedium; var aDragData : ICefDragData) : boolean;
function DataObjectToDragData_Text(var aMedium : TStgMedium; var aDragData : ICefDragData) : boolean;
function DataObjectToDragData_URL(var aMedium : TStgMedium; var aDragData : ICefDragData) : boolean;
function DataObjectToDragData_HTML(var aMedium : TStgMedium; var aDragData : ICefDragData) : boolean;
function DataObjectToDragData_FileDrop(var aMedium : TStgMedium; var aDragData : ICefDragData) : boolean;
function HtmlToCFHtml(var aHTML, aBaseURL : ustring) : AnsiString;
procedure CFHtmlToHtml(const cf_html : AnsiString; var html, base_url : string);
function ZeroFiller(aNumber, aLength : integer) : AnsiString;
function FindStringField(const aString, aFieldName : AnsiString; var aPos : integer) : string;
public
constructor Create;
destructor Destroy; override;
function StartDragging : TCefDragOperation;
function CloneDragData(const aDragData : ICefDragData; aAllowedOps : TCefDragOperations) : boolean;
function DragEnter(const DataObj: IDataObject; grfKeyState: Longint; pt: TPoint; var dwEffect: Longint): HRESULT; override;
function DragOver(grfKeyState: Longint; pt: TPoint; var dwEffect: Longint): HRESULT; override;
function DragLeave: HRESULT; override;
function Drop(const dataObj: IDataObject; grfKeyState: Longint; pt: TPoint; var dwEffect: Longint): HRESULT; override;
property OnDragEnter : TDragEnterEvent read FOnDragEnter write FOnDragEnter;
property OnDragOver : TDragOverEvent read FOnDragOver write FOnDragOver;
property OnDragLeave : TNotifyEvent read FOnDragLeave write FOnDragLeave;
property OnDrop : TDropEvent read FOnDrop write FOnDrop;
end;
implementation
uses
uCEFMiscFunctions, uCEFWriteHandler, uCEFStreamWriter, uCEFConstants;
{$IFDEF FPC}
const
//CFSTR_FILEDESCRIPTORA = 'FileGroupDescriptor'; // CF_FILEGROUPDESCRIPTORA
CFSTR_FILEDESCRIPTORW = 'FileGroupDescriptorW'; // CF_FILEGROUPDESCRIPTORW
CFSTR_FILEDESCRIPTOR = CFSTR_FILEDESCRIPTORW;
CFSTR_FILECONTENTS = 'FileContents'; // CF_FILECONTENTS
{$ENDIF}
// *****************************************************
// **************** TCEFDragAndDropMgr *****************
// *****************************************************
constructor TCEFDragAndDropMgr.Create;
begin
inherited Create;
FOnDragEnter := nil;
FOnDragOver := nil;
FOnDragLeave := nil;
FOnDrop := nil;
FCurrentDragData := nil;
FMozURLFormat := RegisterClipboardFormat('text/x-moz-url');
FHTMLFormat := RegisterClipboardFormat('HTML Format');
FFileDescFormat := RegisterClipboardFormat(CFSTR_FILEDESCRIPTOR);
FFileContentsFormat := RegisterClipboardFormat(CFSTR_FILECONTENTS);
end;
destructor TCEFDragAndDropMgr.Destroy;
begin
FCurrentDragData := nil;
inherited Destroy;
end;
function TCEFDragAndDropMgr.DragDataToDataObject_Unicode(const aDragData : ICefDragData;
var aFormat : TFormatEtc;
var aMedium : TStgMedium) : boolean;
var
TempText : ustring;
begin
Result := False;
TempText := aDragData.GetFragmentText;
if (length(TempText) > 0) then
begin
aFormat.ptd := nil;
aFormat.dwAspect := DVASPECT_CONTENT;
aFormat.lindex := -1;
aFormat.tymed := TYMED_HGLOBAL;
aFormat.cfFormat := CF_UNICODETEXT;
TempText := TempText + #0;
Result := GetStorageForString(aMedium, TempText);
end;
end;
function TCEFDragAndDropMgr.DragDataToDataObject_Text(const aDragData : ICefDragData;
var aFormat : TFormatEtc;
var aMedium : TStgMedium) : boolean;
var
TempText : AnsiString;
begin
Result := False;
TempText := UTF8Encode(aDragData.GetFragmentText);
if (length(TempText) > 0) then
begin
aFormat.ptd := nil;
aFormat.dwAspect := DVASPECT_CONTENT;
aFormat.lindex := -1;
aFormat.tymed := TYMED_HGLOBAL;
aFormat.cfFormat := CF_TEXT;
TempText := TempText + #0;
Result := GetStorageForString(aMedium, TempText);
end;
end;
function TCEFDragAndDropMgr.DragDataToDataObject_HTML(const aDragData : ICefDragData;
var aFormat : TFormatEtc;
var aMedium : TStgMedium) : boolean;
var
TempBaseURL, TempHTML : ustring;
TempAnsi : AnsiString;
begin
Result := False;
TempHTML := aDragData.GetFragmentHtml;
if (length(TempHTML) > 0) then
begin
aFormat.ptd := nil;
aFormat.dwAspect := DVASPECT_CONTENT;
aFormat.lindex := -1;
aFormat.tymed := TYMED_HGLOBAL;
aFormat.cfFormat := FHTMLFormat;
TempBaseURL := aDragData.GetFragmentBaseURL;
TempAnsi := HtmlToCFHtml(TempHTML, TempBaseURL) + #0;
Result := GetStorageForString(aMedium, TempAnsi);
end;
end;
function TCEFDragAndDropMgr.DragDataToDataObject_URL(const aDragData : ICefDragData;
var aFormat : TFormatEtc;
var aMedium : TStgMedium) : boolean;
var
TempURL, TempTitle : ustring;
begin
Result := False;
if aDragData.IsLink then
begin
TempURL := aDragData.GetLinkURL;
TempTitle := aDragData.GetLinkTitle;
if (length(TempURL) > 0) then
begin
aFormat.ptd := nil;
aFormat.dwAspect := DVASPECT_CONTENT;
aFormat.lindex := -1;
aFormat.tymed := TYMED_HGLOBAL;
aFormat.cfFormat := FMozURLFormat;
if (length(TempTitle) > 0) then
TempURL := TempURL + #13 + TempTitle;
TempURL := TempURL + #0;
Result := GetStorageForString(aMedium, TempURL);
end;
end;
end;
function TCEFDragAndDropMgr.DragDataToDataObject_FileDesc(const aDragData : ICefDragData;
var aFormat : TFormatEtc;
var aMedium : TStgMedium) : boolean;
var
TempFileName : ustring;
TempSize : cardinal;
begin
Result := False;
if aDragData.IsFile then
begin
TempSize := aDragData.GetFileContents(nil);
TempFileName := aDragData.GetFileName;
if (TempSize > 0) and (length(TempFileName) > 0) then
begin
aFormat.ptd := nil;
aFormat.dwAspect := DVASPECT_CONTENT;
aFormat.lindex := -1;
aFormat.tymed := TYMED_HGLOBAL;
aFormat.cfFormat := FFileDescFormat;
TempFileName := TempFileName + #0;
Result := GetStorageForFileDescriptor(aMedium, TempFileName);
end;
end;
end;
function TCEFDragAndDropMgr.DragDataToDataObject_FileContents(const aDragData : ICefDragData;
var aFormat : TFormatEtc;
var aMedium : TStgMedium) : boolean;
var
TempHandler : ICefWriteHandler;
TempWriter : ICefStreamWriter;
TempSize : cardinal;
begin
Result := False;
if aDragData.IsFile then
begin
TempSize := aDragData.GetFileContents(nil);
if (TempSize > 0) then
begin
aFormat.ptd := nil;
aFormat.dwAspect := DVASPECT_CONTENT;
aFormat.lindex := -1;
aFormat.tymed := TYMED_HGLOBAL;
aFormat.cfFormat := FFileContentsFormat;
TempHandler := TCefBytesWriteHandler.Create(TempSize);
TempWriter := TCefStreamWriterRef.CreateForHandler(TempHandler);
aDragData.GetFileContents(TempWriter);
TempSize := cardinal(TCefBytesWriteHandler(TempHandler).GetDataSize);
Result := GetStorageForBytes(aMedium, TCefBytesWriteHandler(TempHandler).GetData, TempSize);
end;
end;
end;
function TCEFDragAndDropMgr.ZeroFiller(aNumber, aLength : integer) : AnsiString;
begin
Result := AnsiString(IntToStr(aNumber));
while (length(Result) < aLength) do Result := '0' + Result;
end;
function TCEFDragAndDropMgr.HtmlToCFHtml(var aHTML, aBaseURL : ustring) : AnsiString;
const
CRLF : AnsiString = #13+#10;
HTML_START_TAG : AnsiString = '<html>';
HTML_END_TAG : AnsiString = '</html>';
BODY_START_TAG : AnsiString = '<body>';
BODY_END_TAG : AnsiString = '</body>';
FRAGMENT_START : AnsiString = '<!--StartFragment-->';
FRAGMENT_END : AnsiString = '<!--EndFragment-->';
PATTERN1 : AnsiString = '<<<<<1';
PATTERN2 : AnsiString = '<<<<<2';
PATTERN3 : AnsiString = '<<<<<3';
PATTERN4 : AnsiString = '<<<<<4';
var
TempString, TempDigits : AnsiString;
TempPos : integer;
begin
if (length(aHTML) = 0) then
begin
Result := '';
exit;
end;
TempString := 'Version:0.9' + CRLF +
'StartHTML:' + PATTERN1 + CRLF +
'EndHTML:' + PATTERN2 + CRLF +
'StartFragment:' + PATTERN3 + CRLF +
'EndFragment:' + PATTERN4 + CRLF +
'StartSelection:' + PATTERN3 + CRLF +
'EndSelection:' + PATTERN4;
if (length(aBaseURL) > 0) then
TempString := TempString + CRLF + 'SourceURL:' + Utf8Encode(aBaseURL);
TempString := TempString + CRLF +
HTML_START_TAG + CRLF +
BODY_START_TAG + CRLF +
FRAGMENT_START + CRLF +
Utf8Encode(aHTML) + CRLF +
FRAGMENT_END + CRLF +
BODY_END_TAG + CRLF +
HTML_END_TAG;
TempPos := {$IFDEF DELPHI12_UP}{$IFDEF DELPHI16_UP}System.{$ENDIF}AnsiStrings.{$ENDIF}PosEx(HTML_START_TAG, TempString) + length(HTML_START_TAG);
TempDigits := ZeroFiller(TempPos, length(PATTERN1));
TempString := {$IFDEF DELPHI12_UP}{$IFDEF DELPHI16_UP}System.{$ENDIF}AnsiStrings.{$ENDIF}StringReplace(TempString, PATTERN1, TempDigits, [rfReplaceAll]);
TempPos := {$IFDEF DELPHI12_UP}{$IFDEF DELPHI16_UP}System.{$ENDIF}AnsiStrings.{$ENDIF}PosEx(HTML_END_TAG, TempString);
TempDigits := ZeroFiller(TempPos, length(PATTERN2));
TempString := {$IFDEF DELPHI12_UP}{$IFDEF DELPHI16_UP}System.{$ENDIF}AnsiStrings.{$ENDIF}StringReplace(TempString, PATTERN2, TempDigits, [rfReplaceAll]);
TempPos := {$IFDEF DELPHI12_UP}{$IFDEF DELPHI16_UP}System.{$ENDIF}AnsiStrings.{$ENDIF}PosEx(FRAGMENT_START, TempString) + length(FRAGMENT_START);
TempDigits := ZeroFiller(TempPos, length(PATTERN3));
TempString := {$IFDEF DELPHI12_UP}{$IFDEF DELPHI16_UP}System.{$ENDIF}AnsiStrings.{$ENDIF}StringReplace(TempString, PATTERN3, TempDigits, [rfReplaceAll]);
TempPos := {$IFDEF DELPHI12_UP}{$IFDEF DELPHI16_UP}System.{$ENDIF}AnsiStrings.{$ENDIF}PosEx(FRAGMENT_END, TempString);
TempDigits := ZeroFiller(TempPos, length(PATTERN4));
TempString := {$IFDEF DELPHI12_UP}{$IFDEF DELPHI16_UP}System.{$ENDIF}AnsiStrings.{$ENDIF}StringReplace(TempString, PATTERN4, TempDigits, [rfReplaceAll]);
Result := TempString;
end;
function TCEFDragAndDropMgr.FindStringField(const aString, aFieldName : AnsiString; var aPos : integer) : string;
var
TempLen, i, TempValuePos : integer;
TempString : AnsiString;
begin
aPos := pos(aFieldName, aString);
TempLen := length(aString);
if (aPos > 0) then
begin
TempValuePos := aPos + length(aFieldName);
i := TempValuePos;
while (i <= TempLen) and
{$IFDEF DELPHI12_UP}
not(CharInSet(aString[i], [#13, #10]))
{$ELSE}
not(aString[i] in [#13, #10])
{$ENDIF} do
inc(i);
TempString := copy(aString, TempValuePos, i - TempValuePos);
if (length(TempString) > 0) then
{$IFDEF DELPHI12_UP}
Result := UTF8ToString(TempString);
{$ELSE}
Result := UTF8Decode(TempString);
{$ENDIF}
end
else
Result := '';
end;
procedure TCEFDragAndDropMgr.CFHtmlToHtml(const cf_html : AnsiString; var html, base_url : string);
const
CFHTML_VERSION : AnsiString = 'Version:';
CFHTML_STARTHTML : AnsiString = 'StartHTML:';
CFHTML_ENDHTML : AnsiString = 'EndHTML:';
CFHTML_STARTFRAG : AnsiString = 'StartFragment:';
CFHTML_ENDFRAG : AnsiString = 'EndFragment:';
CFHTML_STARSEL : AnsiString = 'StartSelection:';
CFHTML_ENDSEL : AnsiString = 'EndSelection:';
CFHTML_SOURCEURL : AnsiString = 'SourceURL:';
FRAGMENT_START : AnsiString = '<!--StartFragment';
FRAGMENT_END : AnsiString = '<!--EndFragment';
var
TempHTMLStart, TempHTMLEnd : integer;
TempFragStart, TempFragEnd : integer;
TempVersionPos, TempSourcePos : integer;
TempHTMLStartPos, TempHTMLEndPos : integer;
TempFragStartPos, TempFragEndPos : integer;
TempFragStartCommentPos, TempFragEndCommentPos : integer;
begin
html := '';
base_url := '';
if (FindStringField(cf_html, CFHTML_VERSION, TempVersionPos) <> '0.9') then exit;
TempHTMLStart := StrToIntDef(FindStringField(cf_html, CFHTML_STARTHTML, TempHTMLStartPos), -1);
TempHTMLEnd := StrToIntDef(FindStringField(cf_html, CFHTML_ENDHTML, TempHTMLEndPos), -1);
TempFragStart := StrToIntDef(FindStringField(cf_html, CFHTML_STARTFRAG, TempFragStartPos), -1);
TempFragEnd := StrToIntDef(FindStringField(cf_html, CFHTML_ENDFRAG, TempFragEndPos), -1);
if (TempVersionPos < TempHTMLStartPos) and
(TempHTMLStartPos < TempHTMLEndPos) and
(TempHTMLEndPos < TempFragStartPos) and
(TempFragStartPos < TempFragEndPos) then
begin
TempFragStartCommentPos := pos(FRAGMENT_START, cf_html);
if (TempFragStartCommentPos > 0) then
TempFragStartCommentPos := {$IFDEF DELPHI12_UP}{$IFDEF DELPHI16_UP}System.{$ENDIF}AnsiStrings.{$ENDIF}PosEx('-->', cf_html, TempFragStartCommentPos + length(FRAGMENT_START));
if (TempFragStartCommentPos > 0) then
begin
TempFragStartCommentPos := TempFragStartCommentPos + 3;
TempFragEndCommentPos := {$IFDEF DELPHI12_UP}{$IFDEF DELPHI16_UP}System.{$ENDIF}AnsiStrings.{$ENDIF}PosEx(FRAGMENT_END, cf_html, TempFragStartCommentPos);
end
else
if (TempFragStart > 0) and
(TempFragEnd > 0) then
begin
TempFragStartCommentPos := TempFragStart;
TempFragEndCommentPos := TempFragEnd;
end
else
if (TempHTMLStart > 0) and
(TempHTMLEnd > 0) then
begin
TempFragStartCommentPos := TempHTMLStart;
TempFragEndCommentPos := TempHTMLEnd;
end
else
exit;
if (TempFragStartCommentPos > 0) and
(TempFragEndCommentPos > 0) and
(TempFragEndCommentPos > TempFragStartCommentPos) then
begin
{$IFDEF DELPHI12_UP}
html := UTF8ToString(copy(cf_html, TempFragStartCommentPos, TempFragEndCommentPos - TempFragStartCommentPos));
{$ELSE}
html := UTF8Decode(copy(cf_html, TempFragStartCommentPos, TempFragEndCommentPos - TempFragStartCommentPos));
{$ENDIF}
base_url := FindStringField(cf_html, CFHTML_SOURCEURL, TempSourcePos);
end;
end;
end;
function TCEFDragAndDropMgr.DataObjectToDragData_Unicode(var aMedium : TStgMedium; var aDragData : ICefDragData) : boolean;
var
TempText : string;
TempPointer : pointer;
begin
Result := False;
if (aMedium.hGlobal <> 0) then
begin
TempPointer := GlobalLock(aMedium.hGlobal);
if (TempPointer <> nil) then
begin
TempText := PWideChar(TempPointer);
aDragData.SetFragmentText(TempText);
GlobalUnlock(aMedium.hGlobal);
Result := True;
end;
ReleaseStgMedium(aMedium);
end;
end;
function TCEFDragAndDropMgr.DataObjectToDragData_Text(var aMedium : TStgMedium; var aDragData : ICefDragData) : boolean;
var
TempText : string;
TempPointer : pointer;
begin
Result := False;
if (aMedium.hGlobal <> 0) then
begin
TempPointer := GlobalLock(aMedium.hGlobal);
if (TempPointer <> nil) then
begin
{$IFDEF DELPHI12_UP}
TempText := UTF8ToString(PAnsiChar(TempPointer));
{$ELSE}
TempText := UTF8Decode(PAnsiChar(TempPointer));
{$ENDIF}
aDragData.SetFragmentText(TempText);
GlobalUnlock(aMedium.hGlobal);
Result := True;
end;
ReleaseStgMedium(aMedium);
end;
end;
function TCEFDragAndDropMgr.DataObjectToDragData_URL(var aMedium : TStgMedium; var aDragData : ICefDragData) : boolean;
var
TempText, TempURL, TempTitle : string;
TempPos : integer;
TempPointer : pointer;
begin
Result := False;
if (aMedium.hGlobal <> 0) then
begin
TempPointer := GlobalLock(aMedium.hGlobal);
if (TempPointer <> nil) then
begin
TempText := PWideChar(TempPointer);
TempPos := LastDelimiter(#13, TempText);
if (TempPos <= 0) then TempPos := LastDelimiter(#10, TempText);
if (TempPos > 0) then
begin
TempURL := copy(TempText, 1, pred(TempPos));
TempTitle := copy(TempText, succ(TempPos), length(TempText));
end
else
begin
TempURL := TempText;
TempTitle := TempText;
end;
aDragData.SetLinkURL(TempURL);
aDragData.SetLinkTitle(TempTitle);
GlobalUnlock(aMedium.hGlobal);
Result := True;
end;
ReleaseStgMedium(aMedium);
end;
end;
function TCEFDragAndDropMgr.DataObjectToDragData_HTML(var aMedium : TStgMedium; var aDragData : ICefDragData) : boolean;
var
TempAnsi : AnsiString;
TempHTML, TempBaseURL : string;
TempPointer : pointer;
begin
Result := False;
if (aMedium.hGlobal <> 0) then
begin
TempPointer := GlobalLock(aMedium.hGlobal);
if (TempPointer <> nil) then
begin
TempAnsi := PAnsiChar(TempPointer);
CFHtmlToHtml(TempAnsi, TempHTML, TempBaseURL);
aDragData.SetFragmentHtml(TempHTML);
aDragData.SetFragmentBaseURL(TempBaseURL);
GlobalUnlock(aMedium.hGlobal);
Result := True;
end;
ReleaseStgMedium(aMedium);
end;
end;
function TCEFDragAndDropMgr.DataObjectToDragData_FileDrop(var aMedium : TStgMedium; var aDragData : ICefDragData) : boolean;
var
TempHdrop : HDROP;
TempNumFiles, i, TempLen : integer;
TempText, TempFilePath, TempFileName : string;
TempPointer : pointer;
TempAdded : boolean;
begin
Result := False;
if (aMedium.hGlobal <> 0) then
begin
TempPointer := GlobalLock(aMedium.hGlobal);
if (TempPointer <> nil) then
begin
TempHdrop := THandle(TempPointer);
TempNumFiles := DragQueryFile(TempHdrop, $FFFFFFFF, nil, 0);
TempAdded := False;
i := 0;
SetLength(TempText, succ(MAX_PATH));
while (i < TempNumFiles) do
begin
TempLen := DragQueryFile(TempHdrop, i, @TempText[1], succ(MAX_PATH));
if (TempLen > 0) then
begin
TempFilePath := copy(TempText, 1, TempLen);
TempFileName := ExtractFileName(TempFilePath);
TempAdded := True;
if (length(TempFileName) > 0) then
aDragData.AddFile(TempFilePath, TempFileName)
else
aDragData.AddFile(TempFilePath, TempFilePath);
end;
inc(i);
end;
GlobalUnlock(aMedium.hGlobal);
DragFinish(TempHdrop);
Result := TempAdded;
end;
end;
end;
procedure TCEFDragAndDropMgr.DataObjectToDragData(const aDataObject : IDataObject; var aDragData : ICefDragData);
var
TempEnumFrmt : IEnumFormatEtc;
TempFormat : TFormatEtc;
TempMedium : TStgMedium;
TempUsed : boolean;
begin
try
aDragData := TCefDragDataRef.New;
if (aDataObject <> nil) and (aDataObject.EnumFormatEtc(DATADIR_GET, TempEnumFrmt) = S_OK) then
begin
TempEnumFrmt.Reset;
TempUsed := False;
while (TempEnumFrmt.Next(1, TempFormat, nil) = S_OK) and not(TempUsed) do
begin
try
{$IFNDEF FPC}
TempMedium.unkForRelease := nil;
{$ELSE}
TempMedium.PUnkForRelease := nil;
{$ENDIF}
if ((TempFormat.tymed and TYMED_HGLOBAL) <> 0) and
(aDataObject.GetData(TempFormat, TempMedium) = S_OK) then
begin
if (TempFormat.cfFormat = CF_UNICODETEXT) then TempUsed := DataObjectToDragData_Unicode(TempMedium, aDragData)
else if (TempFormat.cfFormat = CF_TEXT) then TempUsed := DataObjectToDragData_Text(TempMedium, aDragData)
else if (TempFormat.cfFormat = FMozURLFormat) then TempUsed := DataObjectToDragData_URL(TempMedium, aDragData)
else if (TempFormat.cfFormat = FHTMLFormat) then TempUsed := DataObjectToDragData_HTML(TempMedium, aDragData)
else if (TempFormat.cfFormat = CF_HDROP) then TempUsed := DataObjectToDragData_FileDrop(TempMedium, aDragData)
else ReleaseStgMedium(TempMedium);
end;
finally
if (TempFormat.ptd <> nil) then
begin
CoTaskMemFree(TempFormat.ptd);
TempFormat.ptd := nil;
end;
end;
end;
end;
except
on e : exception do
if CustomExceptionHandler('TCEFDragAndDropMgr.DataObjectToDragData', e) then raise;
end;
end;
function TCEFDragAndDropMgr.StartDragging : TCefDragOperation;
var
TempDataObject : IDataObject;
TempDropSource : IDropSource;
TempResEffect : integer;
TempResult : HRESULT;
TempFormatArray : TOLEFormatArray;
TempMediumArray : TOLEMediumArray;
i : integer;
begin
Result := DRAG_OPERATION_NONE;
if (FCurrentDragData <> nil) then
begin
i := 0;
if DragDataToDataObject_Unicode(FCurrentDragData, TempFormatArray[i], TempMediumArray[i]) then inc(i);
if DragDataToDataObject_Text(FCurrentDragData, TempFormatArray[i], TempMediumArray[i]) then inc(i);
if DragDataToDataObject_URL(FCurrentDragData, TempFormatArray[i], TempMediumArray[i]) then inc(i);
if DragDataToDataObject_HTML(FCurrentDragData, TempFormatArray[i], TempMediumArray[i]) then inc(i);
if DragDataToDataObject_FileDesc(FCurrentDragData, TempFormatArray[i], TempMediumArray[i]) then inc(i);
if DragDataToDataObject_FileContents(FCurrentDragData, TempFormatArray[i], TempMediumArray[i]) then inc(i);
if (i > 0) then
begin
TempResEffect := DROPEFFECT_NONE;
TempDataObject := TOLEDataObject.Create(TempFormatArray, TempMediumArray, i);
TempDropSource := TOLEDropSource.Create;
{$IFNDEF FPC}
TempResult := DoDragDrop(TempDataObject, TempDropSource, FOLEEffect, TempResEffect);
{$ELSE}
TempResult := DoDragDrop(TempDataObject, TempDropSource, DWORD(FOLEEffect), LPDWORD(TempResEffect));
{$ENDIF}
if (TempResult <> DRAGDROP_S_DROP) then TempResEffect := DROPEFFECT_NONE;
FCurrentDragData := nil;
DropEffectToDragOperation(TempResEffect, Result);
end;
end;
end;
function TCEFDragAndDropMgr.CloneDragData(const aDragData : ICefDragData; aAllowedOps : TCefDragOperations) : boolean;
begin
if (aDragData <> nil) and
((length(aDragData.GetFragmentText) > 0) or
(length(aDragData.GetFragmentHTML) > 0) or
aDragData.IsLink or
aDragData.IsFile) then
begin
DragOperationToDropEffect(aAllowedOps, FOLEEffect);
FCurrentDragData := aDragData.Clone;
FCurrentDragData.ResetFileContents;
Result := True;
end
else
Result := False;
end;
function TCEFDragAndDropMgr.DragEnter(const dataObj : IDataObject;
grfKeyState : Longint;
pt : TPoint;
var dwEffect : Longint): HRESULT;
var
TempDragData : ICefDragData;
begin
if assigned(FOnDragEnter) then
begin
if (FCurrentDragData <> nil) then
TempDragData := FCurrentDragData
else
DataObjectToDragData(dataObj, TempDragData);
FOnDragEnter(self, TempDragData, grfKeyState, pt, dwEffect);
Result := S_OK;
end
else
Result := E_UNEXPECTED;
end;
function TCEFDragAndDropMgr.DragOver(grfKeyState: Longint; pt: TPoint; var dwEffect: Longint): HResult;
begin
if assigned(FOnDragOver) then
begin
FOnDragOver(self, grfKeyState, pt, dwEffect);
Result := S_OK;
end
else
Result := E_UNEXPECTED;
end;
function TCEFDragAndDropMgr.DragLeave: HResult;
begin
if assigned(FOnDragLeave) then
begin
FOnDragLeave(self);
Result := S_OK;
end
else
Result := E_UNEXPECTED;
end;
function TCEFDragAndDropMgr.Drop(const dataObj : IDataObject;
grfKeyState : Longint;
pt : TPoint;
var dwEffect : Longint): HResult;
begin
if assigned(FOnDrop) then
begin
FOnDrop(self, grfKeyState, pt, dwEffect);
Result := S_OK;
end
else
Result := E_UNEXPECTED;
end;
end.