vcl-dxchartcore-dot-tdxchartcustomseries-403c18c4.md
Provides access to data binding settings.
property DataBinding: TdxChartSeriesCustomDataBinding read; write;
| Type | Description |
|---|---|
| TdxChartSeriesCustomDataBinding |
Stores data binding settings that correspond to the active data access mode.
Cast the property value to the corresponding terminal [TdxChartSeriesCustomDataBinding] descendant to access all public API members. You can call the DataBinding.ClassType function to identify the actual data binding settings type or use the DataBindingClass or DataBindingType property.
Refer to the Remarks section for the full list of available setting classes.
|
Use the DataBindingType or DataBindingClass property to switch between available data access modes.
Different TdxChartCustomSeries class descendants use different data binding setting classes:
An XY series uses the following data binding classes depending on the DataBindingType property value:
| DataBindingType[1] Value | DataBindingClass[2] Value | Description |
|---|---|---|
'Unbound' | TdxChartXYSeriesUnboundDataBinding | An XY chart series is not bound to a dataset. You need to populate series with data points manually. |
'DB' | TdxChartXYSeriesDBDataBinding | An XY chart series connects to a dataset and loads all data records into memory. |
A simple series uses the following data binding classes depending on the DataBindingType property value:
| DataBindingType[1] Value | DataBindingClass[2] Value | Description |
|---|---|---|
Unbound | TdxChartSimpleSeriesUnboundDataBinding | A simple series is not bound to a dataset. You need to populate series with data points manually. |
'DB' | TdxChartSimpleSeriesDBDataBinding | A simple series connects to a dataset and loads all data records into memory. |
The following code example creates three line series with identical appearance settings in bound mode:
var
AXYDiagram: TdxChartXYDiagram;
AXYSeriesAmericas, AXYSeriesEurope, AXYSeriesAfrica: TdxChartXYSeries;
ALineView: TdxChartXYSeriesLineView;
ADataBinding: TdxChartXYSeriesDBDataBinding;
begin
dxChartControl1.BeginUpdate; // Initiates the following batch change
try
dxChartControl1.Titles.Add.Text := 'Historic, Current, and Future Population Projection';
AXYDiagram := dxChartControl1.AddDiagram<TdxChartXYDiagram>;
AXYDiagram.Axes.AxisY.Title.Text := 'Population mid-year, millions';
AXYDiagram.Axes.AxisX.Interlaced := True;
AXYSeriesEurope := AXYDiagram.AddSeries('Europe'); // Creates a new series with the caption "Europe"
AXYSeriesEurope.ShowInLegend := TdxChartSeriesShowInLegend.Diagram;
AXYSeriesEurope.DataBindingClass := TdxChartXYSeriesDBDataBinding;
ADataBinding := AXYSeriesEurope.DataBinding as TdxChartXYSeriesDBDataBinding;
ADataBinding.DataSource := dsPopulation; // Assigns a data source
ADataBinding.DataSource.DataSet := mdPopulation; // Assigns a dataset
ADataBinding.DataSource.DataSet.Active := True; // Enables the assigned dataset
ADataBinding.ArgumentField.FieldName := 'Year'; // Specifies the source dataset field for arguments
ADataBinding.ValueField.FieldName := 'Europe'; // Specifies the source dataset field for values
AXYSeriesEurope.ViewClass := TdxChartXYSeriesLineView; // Selects the Line series View
ALineView := AXYSeriesEurope.View as TdxChartXYSeriesLineView;
ALineView.Markers.Visible := True; // Displays value markers
ALineView.ValueLabels.Visible := True; // Displays value labels
ALineView.Appearance.StrokeOptions.Width := 2; // Increases line width
AXYSeriesAmericas := AXYDiagram.AddSeries; // Creates a new series with the default settings
AXYSeriesAmericas.AssignFrom(AXYSeriesEurope); // Copies all settings from the "Europe" series
AXYSeriesAmericas.Caption := 'Americas'; // Defines a different series caption
// Specifies a different source dataset field for values
ADataBinding := AXYSeriesAmericas.DataBinding as TdxChartXYSeriesDBDataBinding;
ADataBinding.ValueField.FieldName := 'Americas';
AXYSeriesAfrica := AXYDiagram.AddSeries; // Creates a new series with the default settings
AXYSeriesAfrica.AssignFrom(AXYSeriesEurope); // Copies all settings from the "Europe" series
AXYSeriesAfrica.Caption := 'Africa'; // Defines a different series caption
// Specifies a different source dataset field for values
ADataBinding := AXYSeriesAfrica.DataBinding as TdxChartXYSeriesDBDataBinding;
ADataBinding.ValueField.FieldName := 'Africa';
finally
dxChartControl1.EndUpdate; // Calls EndUpdate regardless of the batch operation's success
end;
end;
TdxChartXYDiagram *AXYDiagram;
TdxChartXYSeries *AXYSeriesEurope, *AXSeriesAmericas, *AXYSeriesAfrica;
TdxChartXYSeriesLineView *ALineView;
TdxChartXYSeriesDBDataBinding *ADataBinding;
// ...
dxChartControl1->BeginUpdate(); // Initiates the following batch change
try
{
dxChartControl1->Titles->Add()->Text = "Historic, Current, and Future Population Projection";
AXYDiagram = new TdxChartXYDiagram(dxChartControl1->Owner);
AXYDiagram->SetParentComponent(dxChartControl1);
AXYDiagram->Axes->AxisY->Title->Text = "Population mid-year, millions";
AXYDiagram->Axes->AxisX->Interlaced = true;
AXYSeriesEurope = AXYDiagram->AddSeries("Europe"); // Creates a new series with the caption "Europe"
AXYSeriesEurope->ShowInLegend = TdxChartSeriesShowInLegend::Diagram;
AXYSeriesEurope->DataBindingClass = __classid(TdxChartXYSeriesDBDataBinding);
ADataBinding = dynamic_cast<TdxChartXYSeriesDBDataBinding*>(AXYSeriesEurope->DataBinding);
ADataBinding->DataSource = dsPopulation; // Assigns a data source
ADataBinding->DataSource->DataSet = mdPopulation; // Assigns a dataset
ADataBinding->DataSource->DataSet->Active = true; // Enables the assigned dataset
ADataBinding->ArgumentField->FieldName = "Year"; // Specifies the source dataset field for arguments
ADataBinding->ValueField->FieldName = "Europe"; // Specifies the source dataset field for values
AXYSeriesEurope->ViewClass = __classid(TdxChartXYSeriesLineView); // Selects the Line series View
ALineView := dynamic_cast<TdxChartXYSeriesLineView*>(AXYSeriesEurope->View);
ALineView->Markers->Visible := true; // Displays value markers
ALineView->ValueLabels->Visible = true; // Displays value labels
ALineView->Appearance->StrokeOptions->Width = 2; // Increases line width
AXYSeriesAmericas = AXYDiagram->AddSeries(); // Creates a new series with the default settings
AXYSeriesAmericas->AssignFrom(AXYSeriesEurope); // Copies all settings from the "Europe" series
ADataBinding = dynamic_cast<TdxChartXYSeriesDBDataBinding*>(AXYSeriesAmericas->DataBinding);
ADataBinding->ValueField->FieldName = "Americas"; // Specifies a different source dataset field for values
AXYSeriesAmericas->Caption = "Americas"; // Defines a different series caption
AXYSeriesAfrica = AXYDiagram->AddSeries(); // Creates a new series with the default settings
AXYSeriesAfrica->AssignFrom(AXYSeriesEurope); // Copies all settings from the "Europe" series
ADataBinding = dynamic_cast<TdxChartXYSeriesDBDataBinding*>(AXYSeriesAfrica->DataBinding);
ADataBinding->ValueField->FieldName = "Africa"; // Specifies a different source dataset field for values
AXYSeriesAfrica->Caption = "Africa"; // Defines a different series caption
}
__finally
{
dxChartControl1->EndUpdate(); // Calls EndUpdate regardless of the batch operation's success
}
// ...
The following code example creates three stacked bar series with identical appearance settings in unbound data access mode:
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;
#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
}
// ...
Footnotes
The DataBindingType property setter updates the DataBindingClass and DataBinding property values according to the selected data access mode.
The DataBindingClass property setter updates the DataBindingType and DataBinding property values according to the selected data access mode.
See Also