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TdxChartCustomSeries.DataBindingType Property

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TdxChartCustomSeries.DataBindingType Property

Specifies the active data access mode.

Declaration

delphi
property DataBindingType: string read; write;

Property Value

TypeDescription
string

The name of the active data access mode. Refer to the Remarks section for details.

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Remarks

Use the DataBindingType or DataBindingClass property to switch between available data access modes. Different TdxChartCustomSeries class descendants use different data binding setting classes:

TdxChartXYSeries

An XY series uses the following data binding classes depending on the DataBindingType property value:

DataBindingType[1] ValueDataBindingClass[2] ValueDescription
'DB'TdxChartXYSeriesDBDataBindingAn XY chart series connects to a dataset and loads all data records into memory.
'Unbound'TdxChartXYSeriesUnboundDataBindingAn XY chart series is not bound to a dataset. You need to populate series with data points manually.

TdxChartSimpleSeries

A simple series uses the following data binding classes depending on the DataBindingType property value:

DataBindingType[1] ValueDataBindingClass[2] ValueDescription
'DB'TdxChartSimpleSeriesDBDataBindingA simple series connects to a dataset and loads all data records into memory.
UnboundTdxChartSimpleSeriesUnboundDataBindingA simple series is not bound to a dataset. You need to populate series with data points manually.

Code Example: Create Three Stacked Bar Series in Unbound Mode

The following code example creates three stacked bar series with identical appearance settings in unbound data access mode:

delphi
uses cxDataStorage; // Declares the TcxStringValueType class
// ...
var
  AXYDiagram: TdxChartXYDiagram;
  AXY2018Series, AXY2019Series, AXY2020Series: TdxChartXYSeries;
  AStackedBarView: TdxChartXYSeriesStackedBarView;
  ADataBinding: TdxChartXYSeriesUnboundDataBinding;
begin
  dxChartControl1.BeginUpdate; // Initiates the following batch change
  try
    AXYDiagram := dxChartControl1.AddDiagram<TdxChartXYDiagram>('DevAV Sales By Region');
    AXYDiagram.Title.Appearance.FontOptions.Size := 20;
    AXYDiagram.Axes.AxisY.Title.Text := 'Millions of Dollars';
    AXYDiagram.Axes.AxisY.Title.Appearance.FontOptions.Size := 14;
    AXY2018Series := AXYDiagram.AddSeries('2018'); // Creates a new series with the caption "2018"
    // Selects the unbound data access mode
    AXY2018Series.DataBindingClass := TdxChartXYSeriesUnboundDataBinding;
    ADataBinding := AXY2018Series.DataBinding as TdxChartXYSeriesUnboundDataBinding;
    // Selects the string data type for arguments
    ADataBinding.ArgumentField.ValueTypeClass := TcxStringValueType;
    AXY2018Series.ViewClass := TdxChartXYSeriesStackedBarView; // Selects the Stacked Bar series View
    AStackedBarView := AXY2018Series.View as TdxChartXYSeriesStackedBarView;
    AStackedBarView.ValueLabels.Visible := True; // Displays value labels on bars
    AStackedBarView.ValueLabels.TextFormat := '{V:0.000}'; // Changes the number display format
    AStackedBarView.ValueLabels.Appearance.FontOptions.Bold := True;
    AXY2018Series.Points.Add('Asia', 4.2372);
    AXY2018Series.Points.Add('Australia', 1.7871);
    AXY2018Series.Points.Add('Europe', 3.0884);
    AXY2018Series.Points.Add('North America', 3.4855);
    AXY2018Series.Points.Add('South America', 1.6027);
    AXY2019Series := AXYDiagram.AddSeries; // Creates a new series with the default settings
    AXY2019Series.AssignFrom(AXY2018Series); // Copies all settings from the "2018" series
    AXY2019Series.Caption := '2019'; // Defines a different series caption
    AXY2019Series.Points.Add('Asia', 4.7685);
    AXY2019Series.Points.Add('Australia', 1.9576);
    AXY2019Series.Points.Add('Europe', 3.3579);
    AXY2019Series.Points.Add('North America', 3.7477);
    AXY2019Series.Points.Add('South America', 1.8237);
    AXY2020Series := AXYDiagram.AddSeries('2020'); // Creates a new series with the default settings
    AXY2020Series.AssignFrom(AXY2018Series); // Copies all settings from the "2018" series
    AXY2020Series.Caption := '2020'; // Defines a different series caption
    AXY2020Series.Points.Add('Asia', 5.289);
    AXY2020Series.Points.Add('Australia', 2.2727);
    AXY2020Series.Points.Add('Europe', 3.7257);
    AXY2020Series.Points.Add('North America', 4.1825);
    AXY2020Series.Points.Add('South America', 2.1172);
  finally
    dxChartControl1.EndUpdate; // Calls EndUpdate regardless of the batch operation's success
  end;
end;
cpp
#include "cxDataStorage.hpp" // Declares the TcxStringValueType class
// ...
  TdxChartXYDiagram *AXYDiagram;
  TdxChartXYSeries *AXY2018Series, *AXY2019Series, *AXY2020Series;
  TdxChartXYSeriesStackedBarView *AStackedBarView;
  TdxChartXYSeriesUnboundDataBinding *ADataBinding;
  // ...
  dxChartControl1->BeginUpdate(); // Initiates the following batch change
  try
  {
    AXYDiagram = new TdxChartXYDiagram(dxChartControl1->Owner);
    AXYDiagram->SetParentComponent(dxChartControl1);
    AXYDiagram->Title->Text = "DevAV Sales by Region";
    AXYDiagram->Title->Appearance->FontOptions->Size = 20;
    AXYDiagram->Axes->AxisY->Title->Text = "Millions of Dollars";
    AXYDiagram->Axes->AxisY->Title->Appearance->FontOptions->Size = 14;
    AXYSeries = AXYDiagram->AddSeries("2018"); // Creates a new series with the caption "2018"
    // Selects the unbound data access mode
    AXYSeries->DataBindingClass = __classid(TdxChartXYSeriesUnboundDataBinding);
    ADataBinding = dynamic_cast<TdxChartXYSeriesUnboundDataBinding*>(AXY2018Series->DataBinding);
    // Selects the string data type for arguments
    ADataBinding->ArgumentField->ValueTypeClass = __classid(TcxStringValueType);
    // Selects the Stacked Bar series View
    AXYSeries->ViewClass = __classid(TdxChartXYSeriesStackedBarView);
    AStackedBarView = dynamic_cast<TdxChartXYSeriesStackedBarView*>(AXY2018Series->View);
    AStackedBarView->ValueLabels->Visible = true; // Displays value labels on bars
    AStackedBarView->ValueLabels->TextFormat = "{V:0.000}"; // Changes the number display format
    AStackedBarView->ValueLabels->Appearance->FontOptions->Bold = true;
    AXY2018Series->Points->Add("Asia", 4.2372);
    AXY2018Series->Points->Add("Australia", 1.7871);
    AXY2018Series->Points->Add("Europe", 3.0884);
    AXY2018Series->Points->Add("North America", 3.4855);
    AXY2018Series->Points->Add("South America", 1.6027);
    AXY2019Series = AXYDiagram->AddSeries(); // Creates a new series with the default settings
    AXY2019Series->AssignFrom(AXY2018Series); // Copies all settings from the "2018" series
    AXY2019Series->Caption = "2019"; // Defines a different series caption
    AXY2019Series->Points->Add("Asia", 4.7685);
    AXY2019Series->Points->Add("Australia", 1.9576);
    AXY2019Series->Points->Add("Europe", 3.3579);
    AXY2019Series->Points->Add("North America", 3.7477);
    AXY2019Series->Points->Add("South America", 1.8237);
    AXY2020Series = AXYDiagram->AddSeries(); // Creates a new series with the default settings
    AXY2020Series->AssignFrom(XY2018Series); // Copies all settings from the "2018" series
    AXY2020Series->Caption = "2020"; // Defines a different series caption
    AXY2020Series->Points->Add("Asia", 5.289);
    AXY2020Series->Points->Add("Australia", 2.2727);
    AXY2020Series->Points->Add("Europe", 3.7257);
    AXY2020Series->Points->Add("North America", 4.1825);
    AXY2020Series->Points->Add("South America", 2.1172);
  }
  __finally
  {
    dxChartControl1->EndUpdate(); // Calls EndUpdate regardless of the batch operation's success
  }
  // ...

Default Value

The DataBindingType property’s default value is 'Unbound'.

Footnotes

  1. The DataBindingType property setter updates DataBindingClass and DataBinding property values according to the selected data access mode.

  2. The DataBindingClass property setter updates DataBindingType and DataBinding property values according to the selected data access mode.

See Also

TdxChartCustomSeries Class

TdxChartCustomSeries Members

dxChartCore Unit