jvcllaz: Add new component TDBLookupTreeView with demo.

git-svn-id: https://svn.code.sf.net/p/lazarus-ccr/svn@6870 8e941d3f-bd1b-0410-a28a-d453659cc2b4

components/jvcllaz/run/JvCore/JvJCLUtils.pas

@@ -336,6 +336,11 @@ function StrToBool(const S: string): Boolean;
 function Var2Type(V: Variant; const DestVarType: Integer): Variant;
 function VarToInt(V: Variant): Integer;
 function VarToFloat(V: Variant): Double;
+*************)
+
+function VarIsNullEmpty(const V: Variant): Boolean;
+
+(****************************** NOT CONVERTED ****
 
 { following functions are not documented
   because they do not work properly sometimes, so do not use them }
@@ -1255,7 +1260,7 @@ function FindUnusedFileName(FileName: string; const FileExt: string; NumberPrefi
 implementation
 
 uses
-  Math, LazFileUtils, LclStrConsts,
+  Math, Variants, LazFileUtils, LclStrConsts,
   JvConsts;
 
 (******************** NOT CONVERTED
@@ -2959,6 +2964,14 @@ function VarToFloat(V: Variant): Double;
 begin
   Result := Var2Type(V, varDouble);
 end;
+*********)
+
+function VarIsNullEmpty(const V: Variant): Boolean;
+begin
+  Result := VarIsNull(V) or VarIsEmpty(V);
+end;
+
+(************************** NOT CONVERTED ***
 
 function CopyDir(const SourceDir, DestDir: TFileName): Boolean;
 var

components/jvcllaz/run/JvCore/JvTypes.pas

@@ -307,6 +307,7 @@ type
     ckID: TJvFourCC;
     ckSize: Longint;
   end;
+****************************)
 
   TJvAniHeader = packed record
     dwSizeof: Longint;
@@ -322,7 +323,6 @@ type
 
   TJvChangeColorEvent = procedure(Sender: TObject; Foreground, Background: TColor) of object;
 
-***********)
   TJvLayout = (lTop, lCenter, lBottom);
   TJvBevelStyle = (bsShape, bsLowered, bsRaised);
 

components/jvcllaz/run/JvDB/JvDBTreeView.pas

@@ -48,6 +48,19 @@ Usage:
   - The text to be displayed as node text is taken from field "ItemField"
   - Optionally, there can ba an "IconField" from which the icon index into the
     ImageList is taken.
+
+From http://wiki.delphi-jedi.org/wiki/JVCL_Help:TJvDBTreeView:
+  - MasterField: is equivalent to the absoluteIndex of the TreeView, a unique
+                 ID for each TreeNode or record in the table.
+  - DetailField: is the hierachical link to the parent item, a foreing key
+                 to the master filed in a self relation table
+  - ItemField:   is the field that contain the display name or the caption of
+                 a treeNode.
+  - IconField:   is a integer field that point to a image index on a TImageList
+                 object that contains the icons for the treeView.
+  - StartMasterValue: is the begining level to start build the TreeView,
+                 0 = start from the root itens, 1 = start from the second level,
+                 and so on.
 -----------------------------------------------------------------------------}
 // $Id$
 
@@ -201,9 +214,6 @@ type
     property MasterValue: Variant read FMasterValue;
   end;
 
-  {$IFDEF RTL230_UP}
-  [ComponentPlatformsAttribute(pidWin32 or pidWin64)]
-  {$ENDIF RTL230_UP}
   TJvDBTreeView = class(TJvCustomDBTreeView)
   published
     property DataSource;

components/jvcllaz/run/JvDB/jvdbconst.pas

@@ -0,0 +1,17 @@
+unit JvDBConst;
+
+{$mode objfpc}{$H+}
+
+interface
+
+uses
+  Classes, SysUtils;
+
+resourcestring
+  SPropDefByLookup = 'Property already defined by lookup field.';
+  SDataSourceFixed = 'Operation is not allowed with DataSource.';
+
+implementation
+
+end.
+

components/jvcllaz/run/JvDB/jvdbutils.pas

@@ -132,6 +132,9 @@ procedure CheckRequiredField(Field: TField);
 procedure CheckRequiredFields(const Fields: array of TField);
 procedure GotoBookmarkEx(DataSet: TDataSet; const Bookmark: TBookmark; Mode: TResyncMode = [rmExact, rmCenter]; ForceScrollEvents: Boolean = False);
 
+function GetFieldProperty(ADataSet: TDataSet; AControl: TComponent;
+  const AFieldName: string): TField;
+
 { SQL expressions }
 
 function DateToSQL(Value: TDateTime): string;
@@ -264,6 +267,15 @@ begin
   end;
 end;
 
+function GetFieldProperty(ADataSet: TDataSet; AControl: TComponent;
+  const AFieldName: string): TField;
+begin
+  Result := ADataSet.FindField(AFieldName);
+  if Result = nil then
+    DatabaseErrorFmt(SFieldNotFound, [AFieldName], AControl);
+end;
+
+
 { Refresh Query procedure }
 
 procedure RefreshQuery(Query: TDataSet);