implement the higher level TfpgDrag and TfpgMimeData classes.

These are independant of the backend - they contain common code and interface.

TfpgDrag will be used to initiate a drag action (acting as the source of
a drag), and contain the data available for that drag action.

3 files changed, 58 insertions, 1 deletions

diff --git a/src/corelib/fpg_main.pas b/src/corelib/fpg_main.pas
index e77a025f..fa6b44d5 100644
--- a/src/corelib/fpg_main.pas
+++ b/src/corelib/fpg_main.pas
@@ -29,7 +29,8 @@ uses
   Classes,
   SysUtils,
   fpg_base,
-  fpg_interface;
+  fpg_interface,
+  fpg_impl;
 
 type
   TOrientation = (orVertical, orHorizontal);
@@ -332,6 +333,25 @@ type
   end;
 
 
+  TfpgMimeData = class(TfpgMimeDataImpl)
+  end;
+
+
+  TfpgDrag = class(TfpgDragImpl)
+  private
+    FTarget: TfpgWinHandle;
+    procedure   SetMimeData(const AValue: TfpgMimeDataBase);
+  protected
+    function    GetSource: TfpgWindow; reintroduce;
+  public
+    constructor Create(ASource: TfpgWindow);
+    function    Execute(const ADropActions: TfpgDropActions; const ADefaultAction: TfpgDropAction = daCopy): TfpgDropAction; override;
+    property    Source: TfpgWindow read GetSource;
+    property    Target: TfpgWinHandle read FTarget write FTarget;
+    property    MimeData: TfpgMimeDataBase read FMimeData write SetMimeData;
+  end;
+
+
 var
   fpgStyle:  TfpgStyle;   { TODO -ograemeg : move this into fpgApplication }
   fpgCaret:  TfpgCaret;   { TODO -ograemeg : move this into fpgApplication }
@@ -2386,6 +2406,37 @@ begin
   Result.UpdateImage;
 end;
 
+
+{ TfpgDrag }
+
+procedure TfpgDrag.SetMimeData(const AValue: TfpgMimeDataBase);
+begin
+  if Assigned(FMimeData) then
+    FMimeData.Free;
+  FMimeData := AValue;
+end;
+
+function TfpgDrag.GetSource: TfpgWindow;
+begin
+  Result := TfpgWindow(inherited GetSource);
+end;
+
+constructor TfpgDrag.Create(ASource: TfpgWindow);
+begin
+  inherited Create;
+  FSource := ASource;
+end;
+
+function TfpgDrag.Execute(const ADropActions: TfpgDropActions;
+  const ADefaultAction: TfpgDropAction): TfpgDropAction;
+begin
+  Assert(FMimeData <> nil, ClassName + ': No mimedata was set before starting the drag');
+  Assert(FSource <> nil, ClassName + ': No Source window was specified before starting the drag');
+  inherited Execute(ADropActions, ADefaultAction);
+end;
+
+
+
 initialization
   uApplication    := nil;
   uClipboard      := nil;
diff --git a/src/corelib/x11/fpg_interface.pas b/src/corelib/x11/fpg_interface.pas
index c4adf079..3a1e1920 100644
--- a/src/corelib/x11/fpg_interface.pas
+++ b/src/corelib/x11/fpg_interface.pas
@@ -33,6 +33,8 @@ type
   TfpgApplicationImpl   = TfpgX11Application;
   TfpgClipboardImpl     = TfpgX11Clipboard;
   TfpgFileListImpl      = TfpgX11FileList;
+  TfpgMimeDataImpl      = TfpgX11MimeData;
+  TfpgDragImpl          = TfpgX11Drag;
 
 implementation
 
diff --git a/src/corelib/x11/fpg_x11.pas b/src/corelib/x11/fpg_x11.pas
index 6419818c..166e1205 100644
--- a/src/corelib/x11/fpg_x11.pas
+++ b/src/corelib/x11/fpg_x11.pas
@@ -346,6 +346,10 @@ type
   end;
 
 
+  TfpgX11MimeData = class(TfpgMimeDataBase)
+  end;
+
+
   TfpgX11Drag = class(TfpgDragBase)
   private
     FLastTarget: TfpgWinHandle;