Callbacks in Flutter Pyramid Chart (SfPyramidChart)

13 May 202111 minutes to read

The below Callbacks are for Pyramid chart.

onLegendItemRender

Triggers when the legend item is rendering. Here, you can customize the legend’s text, and shape. The onLegendItemRender Callback contains the following arguments.

  • text - specifies the content of the legend.
  • pointIndex - specifies the current point index that is applicable for Pyramid chart type alone.
  • seriesIndex - specifies the current series index.
  • legendIconType - specifies the shape of the legend.
  • color - to get and set the color of the legend icon.
  • dart
  • @override
        Widget build(BuildContext context) {
        
          return Scaffold(
            body: Center(
              child: SfPyramidChart(
                legend: Legend(isVisible: true),
                onLegendItemRender: (LegendRenderArgs args){
                  args.text = 'Legend Text';
                  args.legendIconType = LegendIconType.diamond;
                }
              )
            )
          );
        }

    onTooltipRender

    Triggers while tooltip is rendering. Here, you can customize the text, header, x and y-positions. The onTooltipRender Callback contains the following arguments.

    • text - specifies the content of the tooltip.
    • header - specifies the header content of the tooltip.
    • locationX - specifies the x position of tooltip.
    • locationY - specifies the y position of tooltip.
    • seriesIndex - specifies the current series index.
    • dataPoints - holds the data point collection.
    • pointIndex - specifies the current point index.
    • viewportPointIndex - to get the viewport index value of the tapped data label.
  • dart
  • late TooltipBehavior _tooltipBehavior;
    
        @override
        void initState(){
          _tooltipBehavior = TooltipBehavior(enable: true);
          super.initState();
        }
    
        @override
        Widget build(BuildContext context) {
        
          return Scaffold(
            body: Center(
              child: SfPyramidChart(
                onTooltipRender: (TooltipArgs args){
                  args.text = 'Custom Text';
                },
                tooltipBehavior: _tooltipBehavior,
              )
            )
          );
        }

    onDataLabelRender

    Triggers when data label is rendering. Text and text styles such as color, font size, and font weight can be customized. The onDataLabelRender Callback contains the following arguments.

    • text - specifies the content of the data label.
    • textStyle - used to change the text color, size, font family, font style, and font weight.
    • pointIndex - specifies the current point index.
    • seriesRenderer - specifies current series.
    • viewportPointIndex - to get the viewport index value of the tapped data label.
    • color - to get and set the color of data label.
  • dart
  • @override
        Widget build(BuildContext context) {
        
          return Scaffold(
            body: Center(
              child: SfPyramidChart(
                onDataLabelRender:(DataLabelRenderArgs args){
                  args.text = 'Data label';
                },
                series: PyramidSeries<ChartData, String>(
                  dataLabelSettings: DataLabelSettings(
                      isVisible: true
                  )
                )
              )
            )
          );
        }

    onLegendTapped

    Triggers when tapping the legend item. The onLegendTapped Callback contains the following arguments.

    • seriesIndex - specifies the current series index.
    • pointIndex - specifies the current point index that is applicable for Pyramid series.
    • series - specifies the current series.
  • dart
  • @override
        Widget build(BuildContext context) {
        
          return Scaffold(
            body: Center(
              child: SfPyramidChart(
                onLegendTapped: (LegendTapArgs args) {
                  print(args.seriesIndex);
                },
                legend: Legend(isVisible: true)
            )
          );
        }

    onSelectionChanged

    Triggers while selection changes. Here you can customize the selectedColor, unselectedColor, selectedBorderColor, selectedBorderWidth, unselectedBorderColor, and unselectedBorderWidth properties. The onSelectionChanged Callback contains the following arguments.

  • dart
  • late electionBehavior _selectionBehavior;
    
        @override
        void initState(){
          _selectionBehavior = SelectionBehavior(
                    enable: true);
          super.initState();
        }
    
        @override
        Widget build(BuildContext context) {
        
          return Scaffold(
            body: Center(
              child: SfPyramidChart(
              onSelectionChanged: (SelectionArgs args){
                  args.selectedColor = Colors.red;
                  args.unselectedColor = Colors.lightGreen;
                },
                series: PyramidSeries<ChartData, String>(
                    selectionBehavior: _selectionBehavior
                )
              )
            )
          );
        }

    onDataLabelTapped

    Triggers when tapping on the data label of the data point in the series. The onDataLabelTapped Callback contains the following arguments.

    • position - specifies the position of the tapped data label in logical pixels.
    • seriesIndex - specifies the series index of the tapped data label
    • pointIndex - specifies the point index of the tapped data label.
    • text - specifies the content of the tapped data label.
    • dataLabelSettings - to get the data label customization options specified in that particular series.
    • viewportPointIndex - to get the viewport index value of the tapped data label.

    NOTE

    This callback will not be called, when the builder is specified for data label (data label template). For this case, custom widget specified in the DataLabelSettings.builder property can be wrapped using the GestureDetector and this functionality can be achieved in the application level.

  • dart
  • @override
        Widget build(BuildContext context) {
          return Container(
            child: SfFunnelChart(
              onDatalabelTapped: (DataLabelTapArgs args) {
                print(args.seriesIndex);                 
              },
              series: PyramidSeries<Sample, DateTime>(
                  dataSource: sample,
                  xValueMapper: (Sample sales, _) => sales.x,
                  yValueMapper: (Sample sales, _) => sales.y,
                  dataLabelSettings: DataLabelSettings(
                    isVisible:true
                  ),
              )
            )
          );
        }

    onPointTapped

    Triggers when tapping the series point. The onPointTapped Callback contains the following arguments.

  • dart
  • @override
          Widget build(BuildContext context) {
          return Scaffold(
            body: Center(
              child: SfPyramidChart(
                onPointTapped: (PointTapArgs args){
                  print(args.seriesIndex);
                  print(args.pointIndex);
                }
              )
            )  
          );
          }