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TdxDBGridController

About

TdxDBGridController is a non visual component with no dependencies providing added functionalities for the TDBGrid object.

Download: https://gitlab.com/lazaruscomponent/dbgridcontroller

Demo project: https://gitlab.com/lazaruscomponent/dbgridcontroller/-/tree/master/demo

Licenses: MPL 2.0 or LGPL.

| TdxDBGridController component

TdxDBGridController will be installed in the Data Controls tab

Features

Main functionalities

A grid controller that provides extra features to your existing TDBGrid.

TDBGrid events to achive the task

For all these events the inherited events are called before they are triggered, it is possible that these cause unexpected behavior, it is therefore necessary to validate the relevance of keeping them or at least validating their execution.

Overriden event of the dataset linked to the TDBGrid

If an OnFilterRecord event is used by the dataset, it will be override by the builtin event of the controller, no inheritance is taken into account in this case. Need this to achive the filtering with no interference.

TdxDBGridController events

OnAfterFilterGrid Event handler triggered after filter execution
OnAfterSortColumn Event handler triggered after sorting a column
OnAggregation Event handler to define which column is showing an aggregation
OnBeforeSortColumn Event handler triggered before sorting a column
OnLocalize Event handler triggered to translate string resources
OnPrepareLookupDataset Event handler triggered to prepare the lookup dataset if needed
OnSortColumn If your dataset is inherited from TBufDataset, TSQLQuery (Lazarus), TMSQuery, TMSTable (Devart), TZQuery, TZTable (ZeosLib) you don't need to use this event handler, the controller will automatically detect the class and set the IndexDef, IndexFieldNames or SortedFields properties accordingly to the dataset you're using. You can use the SQLOrderBy value to requery your dataset on the db server side if needed.

Examples

Aggregation example on 2 lines

pascal
Procedure TForm1.dxDBGridController1Aggregation(Sender: TdxDBGridController);
Begin
   Sender.ColumnPropertyList.ColumnPropertyByName('ProjectManager').FooterAlignment   := taRightJustify;
   Sender.ColumnPropertyList.ColumnPropertyByName('ProjectManager').FooterDisplayText :=
      'Count Distinct : ' + Sender.ColumnPropertyList.Aggregation(agDistinct, 'ProjectManager').AsString;
   
   // Use the FooterPanel property to set the height : dxDBGridControler1.FooterPanel.Height := Self.DBGrid1.DefaultRowHeight * 2;  
   Sender.ColumnPropertyList.ColumnPropertyByName('OpeningDate').FooterAlignment   := taCenter;
   Sender.ColumnPropertyList.ColumnPropertyByName('OpeningDate').FooterDisplayText :=
      'Min : ' + Sender.ColumnPropertyList.Aggregation(agMin, 'OpeningDate').AsString + Char(13) + Char(10) +
      'Max : ' + Sender.ColumnPropertyList.Aggregation(agMax, 'OpeningDate').AsString;
End;
???

Localization

This is an example, French translation of some of the component string resources:

pascal
Procedure TForm1.dxDBGridController1Localize(Sender: TObject; Component: TComponent; ID_Ressource: String; Var Translation: String);
Begin
    If ID_Ressource = msg_search Then
         Translation := 'Recherche...'
      Else If ID_Ressource = msg_first Then
         Translation := 'Aller au début'
      Else If ID_Ressource = msg_prior Then
         Translation := 'Précédent'
      Else If ID_Ressource = msg_next Then
         Translation := 'Suivant'
      Else If ID_Ressource = msg_last Then
         Translation := 'Aller à la fin'
      Else If ID_Ressource = msg_add Then
         Translation := 'Ajouter'
      Else If ID_Ressource = msg_delete Then
         Translation := 'Détruire'
      Else If ID_Ressource = msg_edit Then
         Translation := 'Éditer'
      Else If ID_Ressource = msg_save Then
         Translation := 'Enregistrer'
      Else If ID_Ressource = msg_cancel Then
         Translation := 'Annuler'
      Else If ID_Ressource = msg_refresh Then
         Translation := 'Actualiser'
      Else If ID_Ressource = msg_btncancel Then
         Translation := 'Annuler'
      Else If ID_Ressource = msg_of Then
         Translation := 'de'
      Else If ID_Ressource = msg_nodata Then
         Translation := 'Aucune donnée trouvée!'
      Else If ID_Ressource = msg_columnchooser Then
         Translation := 'Sélectionner les colonnes...'
      Else If ID_Ressource = msg_clearselection Then
         Translation := 'Annuler sélection'
      Else If ID_Ressource = msg_selectall Then
         Translation := 'Tout sélectionner'
      Else If ID_Ressource = msg_sortingasc Then
         Translation := 'Trier en mode croissant'
      Else If ID_Ressource = msg_sortingdesc Then
         Translation := 'Trier en mode décroissant'; 
End; 
???

List of ressourcestring used by the TdxDBGridController

Screenshots

Global search

Multi sort

A Ctrl+Left clic is use to performe a multi column sorting, the index will appear under the sort indicator.

Column filter

Once you have focused on the grid you can have access to the column filter by clicking the filter icon or with the default shortcut Ctrl+J, this shortcut could be changed with the ColumnFilterShortCut property.

Column search and aggregation

It is not mandatory to use the footer panel to display the aggregation, you can use any other control at your convenience. The values are calculated and set in the OnAggregation event. In this example, the FooterPanel height of the TdxDBGridController was set to Self.DBGrid1.DefaultRowHeight * 2 in order to display the result on 2 lines.

TdxDBGridController properties

See also


From the Free Pascal wiki, page "TdxDBGridController", as it stood on 2023-01-23 after a change by Five, out of the wiki's dump of 2024-05-26. Copyright stays with the author who wrote it, according to the old wiki's Licensing page. If you have concerns about this material, message the admin.

Revision 2, last changed by WikiArchive .

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