Methods

This section describes the methods that can be used in code to manipulate objects related to the dxLinearGauge widget.

beginUpdate()

Prevents the widget from refreshing until the endUpdate method is called.

The beginUpdate and endUpdate methods allow you to apply several modifications to the widget at once. After the beginUpdate method is called, the widget does not rerender itself until the endUpdate method is called. The usage of these methods prevents excessive widget updating when changing multiple widget settings at once.

NOTE: It is recommended that you do not perform any actions on a widget within the updating transaction other than changing widget options.

endUpdate()

Enables the widget to refresh after the beginUpdate method call.

The beginUpdate and endUpdate methods allow you to apply several modifications to the widget at once. After the beginUpdate method is called, the widget does not rerender itself until the endUpdate method is called. The usage of these methods prevents excessive widget updating when changing multiple widget settings at once.

NOTE: It is recommended that you do not perform any actions on a widget within the updating transaction other than changing widget options.

hideLoadingIndicator()

Conceals the loading indicator.

Although the loading indicator hides automatically when a gauge is ready, you can hide it from code at the required time using the hideLoadingIndicator() method.

To show the loading indicator, invoke the showLoadingIndicator() method.

Show Example:
jQuery

In this example, the gauge options are assigned five seconds after the example is loaded. You can show/hide the loading indicator using the buttons under the gauge. Note that the loading indicator can be displayed or concealed manually at any time regardless of whether the gauge is ready or not.


                                    

                                    

instance()

Returns an instance of the widget.

Return Value: Object
An instance of the widget.

Use this method to access the widget.

Show Example:
jQuery

In the following example, the instance() method is used to get access to the gauge options. This method is called unlike the other methods. To call the instance() method, the following construction is used:.

$('#linearGaugeContainer').dxLinearGauge('instance')

Use the drop-down menu to change the type of the value indicator.


                                    

                                    

option()

Returns the object representing the configuration options of the widget.

Return Value: Object
The object representing the configuration options of the widget.

Use the fields of the returned object to configure the widget.

Show Example:
jQuery

In this example, the option() method is used to obtain the value of the tooltip | enabled option and display it under the gauge. To change this value, use the check box below.


                                    

                                    

option(optionName)

Gets the value of the specified configuration option of the widget.

Parameters:
optionName: String
The name of the option to get.
Return Value: any
The value of the specified option.

To get the value of a configuration option, specify the path to the field representing this option in the configuration object. For example, pass the "tooltip.enabled" value as the optionName parameter to get the value of the tooltip | enabled option.

Show Example:
jQuery

In this example, the option(optionName) method is used to obtain the value of the tooltip | enabled option and display it under the gauge. To change this value, use the check box below.


                                    

                                    

option(optionName, optionValue)

Sets a value to the specified configuration option of the widget.

Parameters:
optionName: String
The name of the required option.
optionValue: any
The value to be assigned to the required option.

To set a value to the configuration option, specify the path to the field representing this option in the configuration object. For example, to set the tooltip | enabled option to true, pass the "tooltip.enabled" value as the optionName parameter and the "true" value as the optionValue parameter.

Show Example:
jQuery

In this example, the option(optionName, optionValue) method is used to set the value of the tooltip | enabled option at runtime. To change this value, use the check box below.


                                    

                                    

option(options)

Sets one or more widget options.

Parameters:
options: Object
An object containing required configuration options.

To set one or more widget options, pass the object that contains fields representing these options as the options parameter.

This method is useful if you need to configure several widget options at once.

Show Example:
jQuery

In this example, the option(options) method is used to alter a set of options at once. To change the values of the tooltip | enabled and tooltip | arrowLength options, use the check box below.


                                    

                                    

render()

Redraws a widget.

By default, a widget rerenders when the size of the parent window is changed. But there may be situations when a gauge should be rerendered manually, i.e., when the size of the gauge container is changed. To make a widget rerender, use the render() method.

Show Example:
jQuery

Click the 'Change the container size' button to switch between two sizes of the gauge container. You can set the size either to 100x500 or 150x700 pixels. The render() method is used to redraw the gauge after the container size changes.


                                    

                                    

showLoadingIndicator()

Displays the loading indicator.

The loading indicator does not appear automatically. In order to display it, the showLoadingIndicator() method should be invoked.

To hide the loading indicator from code, use the hideLoadingIndicator() method.

Show Example:
jQuery

In this example, the showLoadingIndicator() method invokes when the example loads. Note that it is not necessary to conceal the loading indicator using the hideLoadingIndicator() method, since it executes automatically.


                                    

                                    

subvalues()

Returns an array of gauge subvalues.

Return Value: Array
An array of gauge subvalues.

See the subvalues option description for more information on gauge subvalues.

Show Example:
jQuery

In this example, the subvalues() method is used to obtain a set of gauge subvalues. Initially, all the subvalues are set to 0. Click the button under the gauge to increase one of these subvalues by 1. The subvalue to be increased is chosen randomly.


                                    

                                    

subvalues(subvalues)

Updates gauge subvalues.

Parameters:
subvalues: Array
A new array of gauge subvalues.

Use this method to change gauge subvalues at runtime.

NOTE: It is necessary to set the subvalues option in order to use the subvalues(subvalues) method. Set this option to an empty array, in case you don't need to show subvalues initially.

Show Example:
jQuery

In this example, the subvalues(subvalues) method is used to update gauge subvalues. Initially, all the subvalues are set to 0. Click the button under the gauge to increase one of these subvalues by 1. The subvalue to be increased is chosen randomly.


                                    

                                    

svg()

Returns the widget's SVG markup.

Return Value: String
The widget's SVG markup.

NOTE: This method does not support Internet Explorer 8.

Show Example:
jQuery

Click the Get SVG below the gauge, and the SVG copy of this gauge will appear.


                                    

                                    

value()

Returns the main gauge value.

Return Value: Number
The main gauge value.

See the value option description for more information on the main gauge value.

Show Example:
jQuery

In this example, the value() method is used to obtain the main gauge value. Click the button under the gauge to increase this value by 1. When the gauge needle reaches the end of the scale, a click on this button will decrease the main gauge value.


                                    

                                    

value(value)

Updates a gauge value.

Parameters:
value: Number
A new gauge value.

Use this method to change the main gauge value at runtime.

Show Example:
jQuery

In this example, the value(value) method is used to update the main gauge value. Click the button under the gauge to increase this value by 1. When the gauge needle reaches the end of the scale, a click on this button will decrease the main gauge value.