delphi: Rework example project

- Load the data module first to enable the main form to
  access the data in OnCreate event.
- Aggregate the code for loading and saving layout definitions
  to separate methods.
- Save layout changes to the dataset when a user saves a layout
  in the Report Designer.
- Load layout from the dataset directly before showing report dialogs.
- Use DevExpress message dialogs instead of standard VCL.
- Remove the TdxSkinController component: DevExpress style settings
  are now always available without the need for a component.
- Enable editing layout names in the grid view.
  Disable editing layouts.
  Enable deleting and moving records.
- Remove unused modules in the `uses` section.

Author: NickVolynkin

Delphi/StoreReportInDB.dpr

@@ -12,7 +12,7 @@ begin
   Application.Initialize;
   Application.MainFormOnTaskbar := True;
   Application.Title := 'DevExpress Example: Store Report in a Database';
-  Application.CreateForm(TMainForm, MainForm);
   Application.CreateForm(TDataModule1, DataModule1);
+  Application.CreateForm(TMainForm, MainForm);
   Application.Run;
 end.

Delphi/StoreReportInDB.res

@@ -794,8 +794,8 @@ object DataModule1: TDataModule1
       69616C697A65723E0D0A010B0000005400610062006C0065005200650070006F
       0072007400}
     SortOptions = []
-    Left = 408
-    Top = 112
+    Left = 424
+    Top = 104
     object mdLayoutsLayout: TBlobField
       FieldName = 'Layout'
     end
@@ -816,10 +816,9 @@ object DataModule1: TDataModule1
       ConnectionString = 'XpoProvider=SQLite; Data Source=nwind.db; Mode=ReadOnly'
     end
   end
-  object dxSkinController1: TdxSkinController
-    NativeStyle = False
-    SkinName = 'WXI'
-    Left = 304
-    Top = 104
+  object ApplicationEvents1: TApplicationEvents
+    OnException = ApplicationEvents1Exception
+    Left = 208
+    Top = 264
   end
 end

Delphi/example.dat

@@ -4,8 +4,8 @@ interface
 
 uses
   System.SysUtils, System.Classes, Data.DB, dxmdaset, cxClasses,
-  dxCore, cxLookAndFeels,
-  dxSkinsForm, dxBackend, dxBackend.ConnectionString.SQL;
+  dxCore, cxLookAndFeels, dxMessageDialog,
+  dxSkinsForm, dxBackend, dxBackend.ConnectionString.SQL, Vcl.AppEvnts;
 
 type
   TDataModule1 = class(TDataModule)
@@ -15,7 +15,8 @@   TDataModule1 = class(TDataModule)
     mdLayoutsName: TWideStringField;
     dxBackendDataConnectionManager1: TdxBackendDataConnectionManager;
     ReportsNWindConnectionString: TdxBackendDatabaseSQLConnection;
-    dxSkinController1: TdxSkinController;
+    ApplicationEvents1: TApplicationEvents;
+    procedure ApplicationEvents1Exception(Sender: TObject; E: Exception);
     procedure DataModuleCreate(Sender: TObject);
     procedure DataModuleDestroy(Sender: TObject);
   private
@@ -35,6 +36,11 @@ implementation
 const
   DataFileName = 'data.dat';
 
+procedure TDataModule1.ApplicationEvents1Exception(Sender: TObject; E: Exception);
+begin
+  dxShowMessage(e.Message);
+end;
+
 procedure TDataModule1.DataModuleCreate(Sender: TObject);
 begin
   if FileExists(DataFileName) then

Delphi/uData.dfm

@@ -46,10 +46,6 @@ object MainForm: TMainForm
       object gvLayouts: TcxGridDBTableView
         DataController.DataSource = DataModule1.dsLayouts
         OptionsData.CancelOnExit = False
-        OptionsData.Deleting = False
-        OptionsData.DeletingConfirmation = False
-        OptionsData.Editing = False
-        OptionsData.Inserting = False
         OptionsView.ColumnAutoWidth = True
         OptionsView.GroupByBox = False
         OptionsView.Indicator = True
@@ -60,6 +56,7 @@ object MainForm: TMainForm
         object gvLayoutsLayout: TcxGridDBColumn
           Caption = 'Report Layout'
           DataBinding.FieldName = 'Layout'
+          Options.Editing = False
         end
         object gvLayoutsName: TcxGridDBColumn
           Caption = 'Report Name'

Delphi/uData.pas

@@ -2,17 +2,15 @@
 
 interface
 
-uses
-  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
-  Vcl.Controls, Vcl.Forms, Vcl.Dialogs, cxClasses, dxReport, cxGraphics,
-  cxLookAndFeels, cxLookAndFeelPainters, Vcl.Menus,  cxButtons,
-  cxControls, cxStyles, cxCustomData, cxFilter, cxData,
-  cxDataStorage, cxEdit, cxNavigator, dxDateRanges, dxScrollbarAnnotations,
-  Data.DB, cxDBData, cxGridLevel, cxGridCustomView, cxGridCustomTableView,
-  cxGridTableView, cxGridDBTableView, cxGrid, FireDAC.Comp.DataSet,
-  FireDAC.Comp.Client,
-  Vcl.StdCtrls, dxmdaset, uData,
-  dxLayoutControlAdapters, dxLayoutContainer, dxLayoutControl;
+uses Vcl.Forms, dxMessageDialog, cxGraphics, cxControls, cxLookAndFeels, cxLookAndFeelPainters, Vcl.Menus,
+  cxStyles, cxCustomData, cxFilter, cxData, cxDataStorage, cxEdit, cxNavigator,
+  dxDateRanges, dxScrollbarAnnotations, Data.DB, cxDBData,
+  dxLayoutControlAdapters, dxLayoutContainer, dxReport, cxGridLevel,
+  cxGridCustomTableView, cxGridTableView, cxGridDBTableView, cxClasses,
+  cxGridCustomView, cxGrid, Vcl.StdCtrls, cxButtons, System.Classes,
+  Vcl.Controls, dxLayoutControl;
+
+
 
 type
   TMainForm = class(TForm)
@@ -37,6 +35,8 @@   TMainForm = class(TForm)
     procedure btnNewClick(Sender: TObject);
     procedure dxReport1LayoutChanged(ASender: TdxReport);
   private
+    procedure LoadReportNameAndLayout;
+    procedure SaveReportNameAndLayout;
     { Private declarations }
   public
     { Public declarations }
@@ -49,43 +49,61 @@ implementation
 
 {$R *.dfm}
 
+uses uData;
 
-procedure TMainForm.btnNewClick(Sender: TObject);
-begin
-  DataModule1.mdLayouts.Append
-end;
-
-procedure TMainForm.btnDesignClick(Sender: TObject);
+procedure TMainForm.LoadReportNameAndLayout();
 begin
   if (DataModule1.mdLayouts.RecordCount = 0) and not (DataModule1.mdLayouts.State = dsInsert)  then
   begin
-    ShowMessage('The database is empty');
+    dxShowMessage('The database is empty');
     Exit;
   end;
+  // Load the report name from the database
   dxReport1.ReportName := DataModule1.mdLayoutsName.AsString;
+  // Load the report layout from the database
   dxReport1.Layout.Assign(DataModule1.mdLayoutsLayout);
+end;
+
+procedure TMainForm.SaveReportNameAndLayout();
+begin
+  // Start editing the active dataset record
+  DataModule1.mdLayouts.Edit;
+  // Save the report name
+  DataModule1.mdLayoutsName.AsString := dxReport1.ReportName;
+  // Save the report layout
+  DataModule1.mdLayoutsLayout.Assign(dxReport1.Layout);
+  // Finish editing and post the modified record to the database
+  DataModule1.mdLayouts.Post;
+end;
+
+
+// Handle the OnLayoutChanged event raised when a user saves a report layout in the Report Designer
+procedure TMainForm.dxReport1LayoutChanged(ASender: TdxReport);
+begin
+  SaveReportNameAndLayout;
+end;
+
+// To create a new report layout, create a new dataset record
+procedure TMainForm.btnNewClick(Sender: TObject);
+begin
+  DataModule1.mdLayouts.Append;
+end;
+
+procedure TMainForm.btnDesignClick(Sender: TObject);
+begin
+  LoadReportNameAndLayout;
   dxReport1.ShowDesigner;
 end;
 
 procedure TMainForm.btnPreviewClick(Sender: TObject);
 begin
-  if (DataModule1.mdLayoutsName.AsString = '')  then
+  LoadReportNameAndLayout;
+  if (dxReport1.ReportName = '') then
   begin
-    ShowMessage('The report is not specified');
+    dxShowMessage('The report is not specified');
     Exit;
   end;
-
-  dxReport1.ReportName := DataModule1.mdLayoutsName.AsString;
-  dxReport1.Layout.Assign(DataModule1.mdLayoutsLayout);
   dxReport1.ShowViewer;
 end;
 
-procedure TMainForm.dxReport1LayoutChanged(ASender: TdxReport);
-begin
-  DataModule1.mdLayouts.Edit;
-  DataModule1.mdLayoutsLayout.Assign(dxReport1.Layout);
-  DataModule1.mdLayoutsName.AsString := dxReport1.ReportName;
-  DataModule1.mdLayouts.Post;
-end;
-
 end.