Gauge Class
File
wijmo.gauge.js
Module
wijmo.gauge
Base Class
Control
Derived Classes
LinearGauge, RadialGauge

Base class for the Wijmo Gauge controls (abstract).

Constructor

constructor

constructor(element: any, options?: any): Gauge

Initializes a new instance of the Gauge class.

Parameters
  • element: any

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

  • options: any Optional

    The JavaScript object containing initialization data for the control.

Returns
Gauge

Properties

Static controlTemplate

Gets or sets the template used to instantiate Gauge controls.

Type
any

face

Gets or sets the Range used to represent the gauge's overall geometry and appearance.

Type
Range

format

Gets or sets the format string used to display gauge values as text.

Type
string

getText

Gets or sets a callback that returns customized strings used to display gauge values.

Use this property if you want to customize the strings shown on the gauge in cases where the format property is not enough.

If provided, the callback should be a function as that takes as parameters the gauge, the part name, the value, and the formatted value. The callback should return the string to be displayed on the gauge.

For example:

// callback to convert values into strings
gauge.getText = (gauge, part, value, text) => {
    switch (part) {
        case 'value':
            if (value <= 10) return 'Empty!';
            if (value <= 25) return 'Low...';
            if (value <= 95) return 'Good';
            return 'Full';
        case 'min':
            return 'EMPTY';
        case 'max':
           return 'FULL';
    }
    return text;
}

Type
IGetGaugeText

handleWheel

Gets or sets a value that determines whether the user can edit the gauge value using the mouse wheel.

The default value for this property is **true**.

Type
boolean

hasShadow

Gets or sets a value that indicates whether the gauge displays a shadow effect.

The default value for this property is **true**.

Type
boolean

hostElement

Gets the DOM element that is hosting the control.

Inherited From
Control
Type
HTMLElement

isAnimated

Gets or sets a value that determines whether the Gauge should use animation to show value changes.

The default value for this property is **true**.

Type
boolean

isDisabled

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

Disabled controls cannot get mouse or keyboard events.

Inherited From
Control
Type
boolean

isReadOnly

Gets or sets a value that indicates whether the user can edit the gauge value using the mouse and keyboard.

The default value for this property is **true**.

Type
boolean

isTouching

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

Inherited From
Control
Type
boolean

isUpdating

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

Inherited From
Control
Type
boolean

max

Gets or sets the maximum value that can be displayed on the gauge.

For details about using the min and max properties, please see the Using the min and max properties topic.

Type
number

min

Gets or sets the minimum value that can be displayed on the gauge.

For details about using the min and max properties, please see the Using the min and max properties topic.

Type
number

origin

Gets or sets the starting point used for painting the range.

By default, this property is set to null, which causes the value range to start at the gauge's minimum value, or zero if the minimum is less than zero.

Type
number

pointer

Gets or sets the Range used to represent the gauge's current value.

Type
Range

ranges

Gets the collection of ranges in this gauge.

Type
ObservableArray

rightToLeft

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

Inherited From
Control
Type
boolean

showRanges

Gets or sets a value that indicates whether the gauge displays the ranges contained in the ranges property.

If this property is set to false, the ranges contained in the ranges property are not displayed in the gauge. Instead, they are used to interpolate the color of the pointer range while animating value changes.

The default value for this property is **true**.

Type
boolean

showText

Gets or sets the ShowText values to display as text in the gauge.

The default value for this property is **ShowText.All** for RadialGauge controls, and to **ShowText.None** for LinearGauge controls.

Type
ShowText

showTicks

Gets or sets a property that determines whether the gauge should display tickmarks at each step (or tickSpacing) value.

The tickmarks can be formatted in CSS using the **wj-gauge** and **wj-ticks** class names. For example:

```css .wj-gauge .wj-ticks { stroke-width: 2px; stroke: white; } ```

The default value for this property is **false.

Type
boolean

showTickText

Gets or sets a property that determines whether the gauge should display the text value of each tick mark.

You can use CSS to style the tickmark text:

```css .wj-gauge .wj-tick-text text { opacity: 1; font-family: Courier; font-size: 8pt; fill: purple; } ```

See also the showTicks and tickSpacing properties.

The default value for this property is **false**.

Type
boolean

stackRanges

Gets or sets a value that determines whether the ranges contained in the ranges collection should be stacked within the gauge.

By default, stackRanges is set to false, and the ranges in the ranges collection are displayed with the same thickness as the gauge's face.

Setting stackRanges to true causes the ranges to become narrower, and to be displayed side-by-side.

Type
boolean

step

Gets or sets the amount to add to or subtract from the value property when the user presses the arrow keys or moves the mouse wheel.

Type
number

tabOrder

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.

Inherited From
Control
Type
number

thickness

Gets or sets the thickness of the gauge, on a scale between zero and one.

Setting the thickness to one causes the gauge to fill as much of the control area as possible. Smaller values create thinner gauges.

Type
number

thumbSize

Gets or sets the size of the element that shows the gauge's current value, in pixels.

Type
number

tickSpacing

Gets or sets the spacing between tickmarks.

Set the showTicks property to true if you want the gauge to show tickmarks along its face. By default, the interval between tickmarks is defined by the step property.

Use the tickSpacing property to override the default and use a spacing that is different from the step value. Set the tickSpacing property to null to revert to the default behavior.

Type
number

value

Gets or sets the value displayed on the gauge.

Type
number

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.

  • capture: boolean Optional

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

  • passive: boolean Optional

    Indicates that the handler will never call preventDefault().

Inherited From
Control
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');

```

Parameters
  • classNames: string

    Names of classes to add to the control's host element.

  • template: string

    An HTML string that defines the control template.

  • parts: Object

    A dictionary of part variables and their names.

  • namePart: string Optional

    Name of the part to be named after the host element. This determines how the control submits data when used in forms.

Inherited From
Control
Returns
HTMLElement

beginUpdate

beginUpdate(): void

Suspends notifications until the next call to endUpdate.

Inherited From
Control
Returns
void

containsFocus

containsFocus(): boolean

Checks whether this control contains the focused element.

Inherited From
Control
Returns
boolean

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
Inherited From
Control
Returns
void

dispose

dispose(): void

Disposes of the control by removing its association with the host element.

The dispose method automatically removes any event listeners added with the addEventListener method.

Calling the dispose method is important in applications that create and remove controls dynamically. Failing to dispose of the controls may cause memory leaks.

Returns
void

Static disposeAll

disposeAll(e?: HTMLElement): void

Disposes of all Wijmo controls contained in an HTML element.

Parameters
Inherited From
Control
Returns
void

endUpdate

endUpdate(shouldInvalidate?: boolean): void

Resumes notifications suspended by calls to beginUpdate.

Parameters
  • shouldInvalidate: boolean Optional

    should invalidate the control. Default value for this parameter is true.

Inherited From
Control
Returns
void

focus

focus(): void

Sets the focus to this control.

Inherited From
Control
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').

Inherited From
Control
Returns
Control

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).

Inherited From
Control
Returns
string

hitTest

hitTest(pt: any, y?: number): number

Gets a number that corresponds to the value of the gauge at a given point.

For example:

// hit test a point when the user clicks on the gauge
gauge.hostElement.addEventListener('click', e => {
    var ht = gauge.hitTest(e.pageX, e.pageY);
    if (ht != null) {
        console.log('you clicked the gauge at value ' + ht.toString());
    }
});

Parameters
  • pt: any

    The point to investigate, in window coordinates, or a MouseEvent object, or the x coordinate of the point.

  • y: number Optional

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

Returns
number

initialize

initialize(options: any): void

Initializes the control by copying the properties from a given object.

This method allows you to initialize controls using plain data objects instead of setting the value of each property in code.

For example:

grid.initialize({
  itemsSource: myList,
  autoGenerateColumns: false,
  columns: [
    { binding: 'id', header: 'Code', width: 130 },
    { binding: 'name', header: 'Name', width: 60 } 
  ]
});



// is equivalent to grid.itemsSource = myList; grid.autoGenerateColumns = false; // etc.

The initialization data is type-checked as it is applied. If the initialization object contains unknown property names or invalid data types, this method will throw.

Parameters
  • options: any

    Object that contains the initialization data.

Inherited From
Control
Returns
void

invalidate

invalidate(fullUpdate?: boolean): void

Invalidates the control causing an asynchronous refresh.

Parameters
  • fullUpdate: boolean Optional

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

Inherited From
Control
Returns
void

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 invalidateAll method so the contained Wijmo controls will update their layout information properly.

Parameters
  • e: HTMLElement Optional

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

Inherited From
Control
Returns
void

onGotFocus

onGotFocus(e?: EventArgs): void

Raises the gotFocus event.

Parameters
Inherited From
Control
Returns
void

onInvalidInput

onInvalidInput(e: CancelEventArgs): void

Raises the invalidInput event.

If the event handler cancels the event, the control will keep the invalid input and the focus.

Parameters
Inherited From
Control
Returns
void

onLostFocus

onLostFocus(e?: EventArgs): void

Raises the lostFocus event.

Parameters
Inherited From
Control
Returns
void

onRefreshed

onRefreshed(e?: EventArgs): void

Raises the refreshed event.

Parameters
Inherited From
Control
Returns
void

onRefreshing

onRefreshing(e?: EventArgs): void

Raises the refreshing event.

Parameters
Inherited From
Control
Returns
void

onValueChanged

onValueChanged(e?: EventArgs): void

Raises the valueChanged event.

Parameters
Returns
void

refresh

refresh(fullUpdate?: boolean): void

Refreshes the control.

Parameters
  • fullUpdate: boolean Optional

    Indicates whether to update the control layout as well as the content.

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
  • e: HTMLElement Optional

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

Inherited From
Control
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
  • target: EventTarget Optional

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

  • type: string Optional

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

  • fn: any Optional

    Handler to remove. If null, removes all handlers.

  • capture: boolean Optional

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

Inherited From
Control
Returns
number

Events

gotFocus

Occurs when the control gets the focus.

Inherited From
Control
Arguments
EventArgs

invalidInput

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.

Inherited From
Control
Arguments
CancelEventArgs

lostFocus

Occurs when the control loses the focus.

Inherited From
Control
Arguments
EventArgs

refreshed

Occurs after the control has refreshed its contents.

Inherited From
Control
Arguments
EventArgs

refreshing

Occurs when the control is about to refresh its contents.

Inherited From
Control
Arguments
EventArgs

valueChanged

Occurs when the value of the value property changes.

Arguments
EventArgs