Improved demo, now it adds a third level of sub-grid ( Customers -> Orders -> Order Details )

Author: davidberneda

.gitignore

@@ -48,3 +48,4 @@ demos/FireMonkey/TeeGridFeatures/Win32/
 *.rsm
 demos/VirtualData/Custom Sorting/__recovery/
 __recovery
+*.vlb

demos/FireMonkey/Database/Master_Detail_FireDAC/Customer_Orders.dfm

@@ -1,6 +1,6 @@
 object SampleData: TSampleData
   OnCreate = DataModuleCreate
-  Height = 337
+  Height = 479
   Width = 267
   object Sqlite_demoConnection: TFDConnection
     Params.Strings = (
@@ -37,7 +37,22 @@ object SampleData: TSampleData
       end>
   end
   object FDStanStorageBinLink1: TFDStanStorageBinLink
-    Left = 104
-    Top = 216
+    Left = 108
+    Top = 288
+  end
+  object OrderDetailsTable: TFDQuery
+    Connection = Sqlite_demoConnection
+    FetchOptions.AssignedValues = [evRecordCountMode]
+    FetchOptions.RecordCountMode = cmTotal
+    SQL.Strings = (
+      'SELECT * FROM "Order Details"'
+      'where OrderID = :Order')
+    Left = 109
+    Top = 211
+    ParamData = <
+      item
+        Name = 'ORDER'
+        ParamType = ptInput
+      end>
   end
 end

demos/FireMonkey/Database/Master_Detail_FireDAC/Customer_Orders.pas

@@ -17,6 +17,7 @@   TSampleData = class(TDataModule)
     CustomersTable: TFDQuery;
     OrdersTable: TFDQuery;
     FDStanStorageBinLink1: TFDStanStorageBinLink;
+    OrderDetailsTable: TFDQuery;
     procedure DataModuleCreate(Sender: TObject);
   private
     { Private declarations }
@@ -26,6 +27,7 @@   TSampleData = class(TDataModule)
     { Public declarations }
 
     function OrdersOfCustomer(const ARecNo:Integer):TDataSet;
+    function OrderDetailsOfOrder(const ARecNo:Integer):TDataSet;
   end;
 
 var
@@ -64,6 +66,28 @@ function TSampleData.OrdersOfCustomer(const ARecNo:Integer):TDataSet;
   result:=CloneData(OrdersTable);
 end;
 
+function TSampleData.OrderDetailsOfOrder(const ARecNo:Integer):TDataSet;
+
+  // Return the OrderID for row: ARow
+  function OrderID:String;
+  begin
+    OrdersTable.RecNo:=ARecNo;
+    result:=OrdersTable.FieldByName('OrderID').AsString;
+  end;
+
+  // Execute OrderDetailsTable query for a given OrderID
+  procedure FilterOrderDetails(const AOrderID:String);
+  begin
+    OrderDetailsTable.Close;
+    OrderDetailsTable.ParamByName('Order').AsString:=AOrderID;
+    OrderDetailsTable.Open;
+  end;
+
+begin
+  FilterOrderDetails(OrderID);
+  result:=CloneData(OrderDetailsTable);
+end;
+
 // Return a new clone copy of ADataSet data, all rows
 function TSampleData.CloneData(const ADataSet:TFDDataSet):TDataSet;
 var tmp : TMemoryStream;

demos/FireMonkey/Database/Master_Detail_FireDAC/Master_Detail_FireDAC.fmx

@@ -49,7 +49,6 @@ object MasterDetail: TMasterDetail
       Size.PlatformDefault = False
       TabOrder = 1
       Text = '&Open/Close All'
-      TextSettings.Trimming = None
       OnClick = Button1Click
     end
   end

demos/FireMonkey/Database/Master_Detail_FireDAC/Master_Detail_FireDAC.pas

@@ -21,7 +21,7 @@ interface
 
   FMXTee.Control, FMXTee.Grid,
 
-  Tee.Renders, Tee.Grid.RowGroup, Customer_Orders, Data.Bind.Controls,
+  Tee.Format, Tee.Renders, Tee.Grid.RowGroup, Customer_Orders, Data.Bind.Controls,
   Data.Bind.Components, Data.Bind.DBScope, Data.DB, Fmx.Bind.Navigator;
 
 type
@@ -39,11 +39,16 @@   TMasterDetail = class(TForm)
   private
     { Private declarations }
 
-    Expander : TExpanderRender;
-
     procedure DetailNewGroup(const Sender,NewGroup:TRowGroup);
+
+    procedure EnableDisableSubGrid(const AGroup:TRowGroup; const AEvent:TExpanderGetDataEvent);
+
+    // Sub-Grid level 1
     procedure GetOrders(const Sender: TExpanderRender; const ARow:Integer; out AData:TObject);
 
+    // Sub-Grid level 2
+    procedure GetOrderItems(const Sender: TExpanderRender; const ARow:Integer; out AData:TObject);
+
   public
     { Public declarations }
   end;
@@ -89,37 +94,47 @@ procedure TMasterDetail.Button1Click(Sender: TObject);
   End;
 end;
 
-procedure TMasterDetail.CBEnabledChange(Sender: TObject);
+// This method is used for any sub-grid level, in this example it is used
+// twice, one for Customer->Orders, and another for Orders->Order Details
+procedure TMasterDetail.EnableDisableSubGrid(const AGroup:TRowGroup; const AEvent:TExpanderGetDataEvent);
+var Expander : TExpanderRender;
 begin
   if CBEnabled.IsChecked then
   begin
     // Create "Expander"
-    Expander:=TeeGrid1.Grid.Current.NewExpander;
+    Expander:=AGroup.NewExpander;
 
-    // Setup event
-    Expander.OnGetData:=GetOrders;
+    // Setup data event
+    Expander.OnGetData:=AEvent;
 
     // We don't know in advance if a row can be expanded or not, so set Always
     Expander.AlwaysExpand:=True;
 
     // Set to first Column
-    if TeeGrid1.Columns.Count>0 then
-       TeeGrid1.Columns[0].Render:=Expander;
+    if AGroup.Columns.Count>0 then
+       AGroup.Columns[0].Render:=Expander;
   end
   else
   begin
     // Remove all detail grids
-    TeeGrid1.Rows.Children.Clear;
+    AGroup.Rows.Children.Clear;
 
     // Set first column render to default (no expander)
-    if TeeGrid1.Columns.Count>0 then
-       TeeGrid1.Columns[0].Render:=nil;
+    if AGroup.Columns.Count>0 then
+       AGroup.Columns[0].Render:=nil;
   end;
 end;
 
+procedure TMasterDetail.CBEnabledChange(Sender: TObject);
+begin
+  EnableDisableSubGrid(TeeGrid1.Grid.Current,GetOrders);
+end;
+
 procedure TMasterDetail.DetailNewGroup(const Sender,NewGroup:TRowGroup);
 var tmpTot : TColumnTotals;
 begin
+  EnableDisableSubGrid(NewGroup,GetOrderItems);
+
   // Create a Totals band
   tmpTot:=TColumnTotals.Create(NewGroup.Footer); // <--- set to Footer
 
@@ -149,4 +164,15 @@ procedure TMasterDetail.GetOrders(const Sender: TExpanderRender; const ARow:Inte
   TVirtualDBData(AData).OwnsData:=True;
 end;
 
+// Called when a new sub-sub-grid has been created, to obtain the sub-sub-grid Data
+// The "Order Items" for the current "Order" for the current "Customer"
+procedure TMasterDetail.GetOrderItems(const Sender: TExpanderRender; const ARow:Integer; out AData:TObject);
+begin
+  // Return a new Data using a clone of Order Items rows for a given Order of a given Customer
+  AData:=TVirtualDBData.From(SampleData.OrderDetailsOfOrder(ARow+1));
+
+  // Data should be destroyed automatically
+  TVirtualDBData(AData).OwnsData:=True;
+end;
+
 end.