5.20231.904
wijmo.chart Class FlexChart Wijmo API Class

FlexChart Class

The FlexChart control provides a powerful and flexible way to visualize data.

You can use the FlexChart control to create charts that display data in several formats, including bar, line, symbol, bubble, and others.

To use the FlexChart control, set the FlexChart.itemsSource property to an array containing the data objects, then add one or more Series objects to the FlexChart.series property.

Use the FlexChart.chartType property to define the ChartType used as a default for all series. You may override the chart type for each series by setting the Series.chartType property on the members of the FlexChart.series array.

Example

Heirarchy

Constructors

constructor

  • new FlexChart(element: any, options?: any): FlexChart
  • Initializes a new instance of the FlexChart class.

    Parameters

    • element: any

      The DOM element that hosts the control, or a CSS selector for the host element (e.g. '#theCtrl').

    • Optional options: any

      A JavaScript object containing initialization data for the control.

    Returns FlexChart

Properties

axes

Gets the collection of Axis objects.

axisX

axisX: Axis

Gets or sets the main X axis.

axisY

axisY: Axis

Gets or sets the main Y axis.

binding

binding: string

Gets or sets the name of the property that contains the Y values.

bindingX

bindingX: string

Gets or sets the name of the property that contains the X data values.

chartType

chartType: ChartType

Gets or sets the type of chart to create.

The default value for this property is ChartType.Column.

collectionView

collectionView: ICollectionView

Gets the ICollectionView object that contains the chart data.

dataLabel

dataLabel: DataLabel

Gets or sets the point data label.

footer

footer: string

Gets or sets the text displayed in the chart footer.

footerStyle

footerStyle: any

Gets or sets the style of the chart footer.

header

header: string

Gets or sets the text displayed in the chart header.

headerStyle

headerStyle: any

Gets or sets the style of the chart header.

hostElement

hostElement: HTMLElement

Gets the DOM element that is hosting the control.

interpolateNulls

interpolateNulls: boolean

Gets or sets a value that determines whether to interpolate null values in the data.

If true, the chart interpolates the value of any missing data based on neighboring points. If false, it leaves a break in lines and areas at the points with null values.

The default value for this property is false.

isDisabled

isDisabled: boolean

Gets or sets a value that determines whether the control is disabled.

Disabled controls cannot get mouse or keyboard events.

isTouching

isTouching: boolean

Gets a value that indicates whether the control is currently handling a touch event.

isUpdating

isUpdating: boolean

Gets a value that indicates whether the control is currently being updated.

itemFormatter

itemFormatter: Function

Gets or sets the item formatter function that allows you to customize the appearance of the chart elements.

If specified, the function should take three parameters: the chart's IRenderEngine responsible for rendering elements on the chart, a HitTestInfo parameter that describes the element being rendered, and a function that provides the default rendering for the item.

For example:

itemFormatter: function (engine, hitTestInfo, defaultRenderer) {
  var ht = hitTestInfo,
      binding = 'downloads';

  // check that this is the right series/element
  if (ht.series.binding == binding && ht.pointIndex > 0 &&
      ht.chartElement == ChartElement.SeriesSymbol) {

    // get current and previous values
    var chart = ht.series.chart,
        items = chart.collectionView.items,
        valNow = items[ht.pointIndex][binding],
        valPrev = items[ht.pointIndex - 1][binding];

    // add line if value is increasing
    if (valNow > valPrev) {
      var pt1 = chart.dataToPoint(ht.pointIndex, valNow),
          pt2 = chart.dataToPoint(ht.pointIndex - 1, valPrev);
      engine.drawLine(pt1.x, pt1.y, pt2.x, pt2.y, null, {
        stroke: 'gold',
        strokeWidth: 6
      });
    }
  }

  // render element as usual
  defaultRenderer();
}

{@sample: Chart/LineArea/CustomLineSegments/purejs Example}

itemsSource

itemsSource: any

Gets or sets the array or ICollectionView object that contains the data used to create the chart.

legend

legend: Legend

Gets or sets the chart legend.

legendToggle

legendToggle: boolean

Gets or sets a value indicating whether clicking legend items toggles the series visibility in the chart.

The default value for this property is false.

options

options: any

Gets or sets various chart options.

The following options are supported:

bubble.maxSize: Specifies the maximum size of symbols in the Bubble chart. The default value is 30 pixels.

bubble.minSize: Specifies the minimum size of symbols in the Bubble chart. The default value is 5 pixels.

chart.options = {
  bubble: { minSize: 5, maxSize: 30 }
}

funnel.neckWidth: Specifies the neck width as a percentage for the Funnel chart. The default value is 0.2.

funnel.neckHeight: Specifies the neck height as a percentage for the Funnel chart. The default value is 0.

funnel.type: Specifies the type of Funnel chart. It should be 'rectangle' or 'default'. neckWidth and neckHeight don't work if type is set to rectangle.

chart.options = {
  funnel: { neckWidth: 0.3, neckHeight: 0.3, type: 'rectangle' }
}

groupWidth: Specifies the group width for the Column charts, or the group height for the Bar charts. The group width can be specified in pixels or as percentage of the available space. The default value is '70%'.

chart.options = {
  groupWidth : 50; // 50 pixels
}
chart.options = {
  groupWidth : '100%'; // 100% pixels
}

palette

palette: string[]

Gets or sets an array of default colors to use for displaying each series.

The array contains strings that represents CSS colors. For example:

// use colors specified by name
chart.palette = ['red', 'green', 'blue'];
// or use colors specified as rgba-values
chart.palette = [
  'rgba(255,0,0,1)',
  'rgba(255,0,0,0.8)',
  'rgba(255,0,0,0.6)',
  'rgba(255,0,0,0.4)'];

There is a set of predefined palettes in the Palettes class that you can use, for example:

chart.palette = Palettes.coral;

plotAreas

Gets the collection of PlotArea objects.

plotMargin

plotMargin: any

Gets or sets the plot margin in pixels.

The plot margin represents the area between the edges of the control and the plot area.

By default, this value is calculated automatically based on the space required by the axis labels, but you can override it if you want to control the precise position of the plot area within the control (for example, when aligning multiple chart controls on a page).

You may set this property to a numeric value or to a CSS-style margin specification. For example:

// set the plot margin to 20 pixels on all sides
chart.plotMargin = 20;
// set the plot margin for top, right, bottom, left sides
chart.plotMargin = '10 15 20 25';
// set the plot margin for top/bottom (10px) and left/right (20px)
chart.plotMargin = '10 20';

renderEngine

renderEngine: IRenderEngine

Gets or sets the chart render engine.

rightToLeft

rightToLeft: boolean

Gets a value indicating whether the control is hosted in an element with right-to-left layout.

rotated

rotated: boolean

Gets or sets a value indicating whether to flip the axes so that X becomes vertical and Y becomes horizontal.

The default value for this property is false.

selection

selection: SeriesBase

Gets or sets the selected chart series.

selectionMode

selectionMode: SelectionMode

Gets or sets an enumerated value indicating whether or what is selected when the user clicks the chart.

The default value for this property is SelectionMode.None.

series

Gets the collection of Series objects.

stacking

stacking: Stacking

Gets or sets a value that determines whether and how the series objects are stacked.

The default value for this property is Stacking.None.

symbolSize

symbolSize: number

Gets or sets the size of the symbols used for all Series objects in this FlexChart.

This property may be overridden by the symbolSize property on each Series object.

The default value for this property is 10 pixels.

tabOrder

tabOrder: number

Gets or sets a value of the tabindex attribute associated with the control.

tabindex attribute value can be defined statically for a Wijmo control by specifying it on the control's host HTML element. But this value can't be changed later during application lifecycle, because Wijmo controls have complex structure, and the control may need to propagate this attribute value to its internal element to work properly.

Because of this, to read or change control's tabindex dynamically, you should do it using this property.

tooltip

tooltip: ChartTooltip

Gets the chart Tooltip object.

The tooltip content is generated using a template that may contain any of the following parameters:

  • propertyName: Any property of the data object represented by the point.
  • seriesName: Name of the series that contains the data point (FlexChart only).
  • pointIndex: Index of the data point.
  • value: Value of the data point (y-value for FlexChart, item value for FlexPie).
  • x: x-value of the data point (FlexChart only).
  • y: y-value of the data point (FlexChart only).
  • name: Name of the data point (x-value for FlexChart or legend entry for FlexPie).

To modify the template, assign a new value to the tooltip's content property. For example:

chart.tooltip.content = '<b>{seriesName}</b> ' +
   '<img src="resources/{x}.png"/><br/>{y}';

You can disable chart tooltips by setting the template to an empty string.

You can also use the tooltip property to customize tooltip parameters such as Tooltip.showDelay and Tooltip.hideDelay:

chart.tooltip.showDelay = 1000;

See ChartTooltip properties for more details and options.

Methods

addEventListener

  • addEventListener(target: EventTarget, type: string, fn: any, capture?: boolean, passive?: boolean): void
  • Adds an event listener to an element owned by this Control.

    The control keeps a list of attached listeners and their handlers, making it easier to remove them when the control is disposed (see the dispose and removeEventListener methods).

    Failing to remove event listeners may cause memory leaks.

    The passive parameter is set to false by default, which means the event handler may call event.preventDefault(). If you are adding passive handlers to touch or wheel events, setting this parameter to true will improve application performance.

    For details on passive event listeners, please see Improving scrolling performance with passive listeners.

    Parameters

    • target: EventTarget

      Target element for the event.

    • type: string

      String that specifies the event.

    • fn: any

      Function to execute when the event occurs.

    • Optional capture: boolean

      Whether the listener should be handled by the control before it is handled by the target element.

    • Optional passive: boolean

      Indicates that the handler will never call preventDefault().

    Returns void

applyTemplate

  • applyTemplate(classNames: string, template: string, parts: Object, namePart?: string): HTMLElement
  • Applies the template to a new instance of a control, and returns the root element.

    This method should be called by constructors of templated controls. Therefore, this method is not available. It is responsible for binding the template parts to the corresponding control members.

    For example, the code below applies a template to an instance of an InputNumber control. The template must contain elements with the 'wj-part' attribute set to 'input', 'btn-inc', and 'btn-dec'. The control members '_tbx', '_btnUp', and '_btnDn' will be assigned references to these elements.

    this.applyTemplate('wj-control wj-inputnumber', templateString, {
      _tbx: 'input',
      _btnUp: 'btn-inc',
      _btnDn: 'btn-dec'
    }, 'input');

    @param classNames Names of classes to add to the control's host element. @param template An HTML string that defines the control template. @param parts A dictionary of part variables and their names. @param namePart Name of the part to be named after the host element. This determines how the control submits data when used in forms.

    Parameters

    • classNames: string
    • template: string
    • parts: Object
    • Optional namePart: string

    Returns HTMLElement

beginUpdate

  • beginUpdate(): void

containsFocus

  • containsFocus(): boolean
  • Checks whether this control contains the focused element.

    Returns boolean

dataToPoint

  • dataToPoint(pt: any, y?: number): Point
  • Converts a Point from data coordinates to control coordinates.

    Parameters

    • pt: any

      Point in data coordinates, or X coordinate of a point in data coordinates.

    • Optional y: number

      Y coordinate of the point (if the first parameter is a number).

    Returns Point

    The Point in control coordinates.

deferUpdate

  • deferUpdate(fn: Function): void
  • Executes a function within a beginUpdate/endUpdate block.

    The control will not be updated until the function has been executed. This method ensures endUpdate is called even if the function throws an exception.

    Parameters

    • fn: Function

      Function to be executed.

    Returns void

dispose

  • dispose(): void

endUpdate

  • endUpdate(): void

focus

  • focus(): void
  • Sets the focus to this control.

    Returns void

getTemplate

  • getTemplate(): string
  • Gets the HTML template used to create instances of the control.

    This method traverses up the class hierarchy to find the nearest ancestor that specifies a control template. For example, if you specify a prototype for the ComboBox control, which does not specify a template, it will override the template defined by the DropDown base class (the nearest ancestor that does specify a template).

    Returns string

hasOwnProperty

  • hasOwnProperty(v: PropertyKey): boolean
  • Determines whether an object has a property with the specified name.

    Parameters

    • v: PropertyKey

      A property name.

    Returns boolean

hitTest

  • Gets a HitTestInfo object with information about the specified point.

    Parameters

    • pt: any

      The point to investigate, in window coordinates.

    • Optional y: number

      The Y coordinate of the point (if the first parameter is a number).

    Returns HitTestInfo

    A HitTestInfo object with information about the point.

invalidate

  • invalidate(fullUpdate?: boolean): void
  • Invalidates the control causing an asynchronous refresh.

    Parameters

    • Optional fullUpdate: boolean

      Whether to update the control layout as well as the content.

    Returns void

isPrototypeOf

  • isPrototypeOf(v: Object): boolean
  • Determines whether an object exists in another object's prototype chain.

    Parameters

    • v: Object

      Another object whose prototype chain is to be checked.

    Returns boolean

onGotFocus

onInvalidInput

onItemsSourceChanged

onItemsSourceChanging

onRefreshed

onRefreshing

onRendered

onRendering

onSelectionChanged

onSeriesVisibilityChanged

pageToControl

  • pageToControl(pt: any, y?: number): Point
  • Converts page coordinates to control coordinates.

    Parameters

    • pt: any

      The point of page coordinates or x value of page coordinates.

    • Optional y: number

      The y value of page coordinates. Its value should be a number, if pt is a number type. However, the y parameter is optional when pt is Point type.

    Returns Point

pointToData

  • pointToData(pt: any, y?: number): Point
  • Converts a Point from control coordinates to chart data coordinates.

    Parameters

    • pt: any

      The point to convert, in control coordinates.

    • Optional y: number

      The Y coordinate of the point (if the first parameter is a number).

    Returns Point

    The point in chart data coordinates.

propertyIsEnumerable

  • propertyIsEnumerable(v: PropertyKey): boolean
  • Determines whether a specified property is enumerable.

    Parameters

    • v: PropertyKey

      A property name.

    Returns boolean

refresh

  • refresh(fullUpdate?: boolean): void
  • Refreshes the chart.

    Parameters

    • Optional fullUpdate: boolean

      A value indicating whether to update the control layout as well as the content.

    Returns void

removeEventListener

  • removeEventListener(target?: EventTarget, type?: string, fn?: any, capture?: boolean): number
  • Removes one or more event listeners attached to elements owned by this Control.

    Parameters

    • Optional target: EventTarget

      Target element for the event. If null, removes listeners attached to all targets.

    • Optional type: string

      String that specifies the event. If null, removes listeners attached to all events.

    • Optional fn: any

      Handler to remove. If null, removes all handlers.

    • Optional capture: boolean

      Whether the listener is capturing. If null, removes capturing and non-capturing listeners.

    Returns number

    The number of listeners removed.

saveImageToDataUrl

  • saveImageToDataUrl(format: ImageFormat, done: Function): void
  • Saves the chart to an image data url.

    NOTE: This method does not work in IE browsers. If you require IE support, add the flex-chart.render module to the page.

    Parameters

    • format: ImageFormat

      The ImageFormat for the exported image.

    • done: Function

      A function to be called after data url is generated. The function gets passed the data url as its argument.

    Returns void

saveImageToFile

  • saveImageToFile(filename: string): void
  • Saves the chart to an image file.

    NOTE: This method does not work in IE browsers. If you require IE support, add the wijmo.chart.render module to the page.

    Parameters

    • filename: string

      The filename for the exported image file including extension. Supported types are PNG, JPEG and SVG.

    Returns void

saveSvgToDataUrl

  • saveSvgToDataUrl(done: Function, embedCss?: boolean): void
  • Saves the chart to a data url as SVG image.

    Parameters

    • done: Function

      A function to be called after data url is generated. The function gets passed the data url as its argument.

    • Optional embedCss: boolean

      Whether to include CSS styles to SVG image.

    Returns void

saveSvgToFile

  • saveSvgToFile(filename: string, embedCss?: boolean): void
  • Saves the chart to an SVG image file.

    Parameters

    • filename: string

      The filename for the exported image file including extension.

    • Optional embedCss: boolean

      Whether to include CSS styles to SVG image.

    Returns void

toLocaleString

  • toLocaleString(): string
  • Returns a date converted to a string using the current locale.

    Returns string

toString

  • toString(): string
  • Returns a string representation of an object.

    Returns string

valueOf

  • valueOf(): Object
  • Returns the primitive value of the specified object.

    Returns Object

Static disposeAll

  • disposeAll(e?: HTMLElement): void
  • Disposes of all Wijmo controls contained in an HTML element.

    Parameters

    • Optional e: HTMLElement

      Container element.

    Returns void

Static getControl

  • getControl(element: any): Control
  • Gets the control that is hosted in a given DOM element.

    Parameters

    • element: any

      The DOM element that hosts the control, or a CSS selector for the host element (e.g. '#theCtrl').

    Returns Control

Static invalidateAll

  • invalidateAll(e?: HTMLElement): void
  • Invalidates all Wijmo controls contained in an HTML element.

    Use this method when your application has dynamic panels that change the control's visibility or dimensions. For example, splitters, accordions, and tab controls usually change the visibility of its content elements. In this case, failing to notify the controls contained in the element may cause them to stop working properly.

    If this happens, you must handle the appropriate event in the dynamic container and call the Control.invalidateAll method so the contained Wijmo controls will update their layout information properly.

    Parameters

    • Optional e: HTMLElement

      Container element. If set to null, all Wijmo controls on the page will be invalidated.

    Returns void

Static refreshAll

  • refreshAll(e?: HTMLElement): void
  • Refreshes all Wijmo controls contained in an HTML element.

    This method is similar to invalidateAll, except the controls are updated immediately rather than after an interval.

    Parameters

    • Optional e: HTMLElement

      Container element. If set to null, all Wijmo controls on the page will be invalidated.

    Returns void

Events

gotFocus

gotFocus: Event<Control, EventArgs>

Occurs when the control gets the focus.

invalidInput

invalidInput: Event<Control, CancelEventArgs>

Occurs when invalid input is detected.

Invalid input may occur when the user types or pastes a value that cannot be converted to the proper type, or a value that is outside the valid range.

If the event handler cancels the event, the control will retain the invalid content and the focus, so users can correct the error.

If the event is not canceled, the control will ignore the invalid input and will retain the original content.

itemsSourceChanged

itemsSourceChanged: Event<FlexChartBase, EventArgs>

Occurs after the chart has been bound to a new items source.

itemsSourceChanging

itemsSourceChanging: Event<FlexChartBase, CancelEventArgs>

Occurs before the chart is bound to a new items source.

lostFocus

lostFocus: Event<Control, EventArgs>

Occurs when the control loses the focus.

refreshed

refreshed: Event<Control, EventArgs>

Occurs after the control has refreshed its contents.

refreshing

refreshing: Event<Control, EventArgs>

Occurs when the control is about to refresh its contents.

rendered

Occurs after the chart finishes rendering.

rendering

Occurs before the chart starts rendering data.

selectionChanged

selectionChanged: Event<FlexChartBase, EventArgs>

Occurs after the selection changes, whether programmatically or when the user clicks the chart. This is useful, for example, when you want to update details in a textbox showing the current selection.

seriesVisibilityChanged

seriesVisibilityChanged: Event<FlexChartCore, SeriesEventArgs>

Occurs when the series visibility changes, for example when the legendToggle property is set to true and the user clicks the legend.