Number Slider Form Element

The Number Slider form element allows the user to select a number using a slider control or by typing the number.

To use a number slider, the user drags the handle to the left or right (). The box shows the currently selected number. Alternatively, the user can use the arrows to change the number () or type a number directly into the box.

Example of the Number Slider form element, shown in a Geocortex viewer

See also...

Number Form Element

Number Slider Properties

The following table describes the properties of the Number Slider form element. Some properties can be configured in the Properties panel in Workflow Designer. These properties have configuration information in the table. Similarly, some properties can be accessed in expressions. These properties have information about how to access the property in an expression.

If a property can be configured in the Properties panel and accessed in expressions, the property has two names: the name that appears in the Properties panel and the name that is used in expressions. Both names are given in the table. Sometimes the names only differ in capitalization, for example, Visible (in the Properties panel) or visible (in expressions).

Properties of the Number Slider Form Element

Default Value

Type: Number

The number that appears initially in the Number Slider box. This also controls the initial position of the slider. If you leave Default Value blank, the median value will appear in the Number Slider box and the slider will be positioned at the midpoint.

Description

Type: String

A description of the element. The description appears below the element's title.

You can use the Description property to describe what the element represents or to provide instructions to the user about how to use the element.

You can format the description using Markdown.

Element ID

Type: String

The element's ID, which is used in other form elements and activities to access the element's properties, including the user's input. The ID must be unique across all elements in the form.

You cannot get or set the value of the Element ID property in an expression—you can only use the value that you configured for it. To use the Element ID property in an expression:

${Display Form ID}.state.{Element ID}.{property name}

For example:

$form1.state.numberSlider1.visible

Enabled

Type: Boolean

Name in Properties Panel: Enabled

Name to Use in Expressions: enabled

Indicates whether the number slider is enabled in the running workflow. When a number slider is enabled, the user can select a number. When a number slider is disabled, the user can see the number slider but cannot interact with it. Disabled elements appear dimmed or shaded in the running workflow.

By default, number sliders are enabled. To disable a number slider initially, clear the Enabled checkbox. You may want to change the property's value at run time depending on the user's input in a previous form element.

To access the enabled property in an expression:

${Display Form ID}.state.{Element ID}.enabled

For example:

$form1.state.numberSlider1.enabled

error

Type: String | MarkdownRef

Indicates whether an error occurred in the element.

MarkdownRef objects have a markdown property of type String that represents the Markdown text.

We recommend using the Set Form Element Error and Clear Form Element Error activities to work with errors in form elements.

Lower Bound

Type: Number

The slider's minimum value. If you leave Lower Bound blank, the minimum value will be 0 (zero). The lowest value you can set Lower Bound to is JavaScript's minimum value.

Precision

Type: Number

They number of decimal digits to show, for example:

  • 0 shows integers (...-2, -1, 0, 1, 2...), for example, 154 or -12;

  • 1 shows one decimal place (...-0.2, -0.1, 0, 0.1, 0.2...), for example, 1.9 or -52.0;

    2 shows two decimal places (...-0.02, -0.01, 0, 0.01, 0.02...), for example, 94800.01 or -16.99;

    and so on.

  • -1 rounds to the nearest ten (...-20, -10, 0, 10, 20...), for example, 6040 or -330;

    -2 rounds to the nearest hundred (...-200, -100, 0, 100, 200...), for example, 42100 or -800;

    and so on.

The value must be within the lower and upper bounds. If the user types in a number that is below the lower bound, the number is rounded up to the lower bound. If the user types in a number that is above the upper bound, the number is rounded down to the upper bound.

Step Size

Type: Number

The amount by which the number in the Number Slider box increases or decreases each time the user drags the slider or clicks the up arrow or down arrow . If you leave Step Size blank or you enter a step size that is 0 or negative, the step size will be 1.

If the precision is negative, the step size should be at least as big as the amount by which the precision rounds the number.

For example, if the precision is -2, the number will be rounded to the nearest hundred. If you set the step size to anything less than 100, the number will increase and decrease by 100.

Title

Type: String

The element's title, which appears at the top of the element.

You may want to change the title to describe what the element represents in your workflow. Descriptive titles make forms easier to understand.

You can format the title using Markdown.

Tooltip

Type: String

A message that displays when the user hovers the mouse pointer over the number slider. You may want to use the tooltip to provide help to the user.

type

Type: String

The variety of form element. Number sliders are type "NumberSlider".

Use the type property to find out the variety of a form element in a form with many elements: loop through ${Display Form ID}.state, comparing each element to the known form types and performing some action on the elements that meet your type criteria.

To access the type property in an expression:

${Display Form ID}.state.{Element ID}.type

For example:

$form1.state.numberSlider1.type

Upper Bound

Type: Number

The slider's maximum value. If you leave Upper Bound blank, the maximum value will be 100. The highest value you can set Upper Bound to is JavaScript's maximum value.

value

Type: NumberRef

The currently selected number.

NumberRef objects have a display property of type String that represents the display value of the number and a numeric property of type Number that is the actual number value.

To access the value property in an expression:

${Display Form ID}.state.{Element ID}.value

For example:

$form1.state.numberSlider1.value

Visible

Type: Boolean

Name in Properties Panel: Visible

Name to Use in Expressions: visible

Indicates whether the element is visible to the user. By default, number sliders are visible. If you want to hide the element initially, clear the Visible checkbox. You may want to change the visibility at run time depending on the user's input in a previous form element.

To access the visible property in an expression:

${Display Form ID}.state.{Element ID}.visible

For example:

$form1.state.numberSlider1.visible

Number Slider Events

The following table describes the events associated with the Number Slider form element. As in Workflow Designer, the events are listed in the order that they fire.

Events for the Number Slider Form Element

load

The load event fires when the element finishes loading.

You can use the load event to set one or more of the element's properties at run time. For example, you could set the number slider's initial value.

change

The change event fires when the user moves the slider, clicks an arrow , or clicks away from the number slider box after changing the number in the box.

You can use the change event to create dependencies between form elements. For example, you could configure a change subworkflow that enables or disables other form elements depending on the user's selection.

The change event fires every time the user's selection changes by one Step Size. This means that the number slider's change subworkflow can run multiple times. Because of this, you should make sure that the change subworkflow is not computationally intensive or long running.

validate

The validate event fires when the user clicks a button that causes validation.

You can use the validate event to verify that the user's input is valid before allowing the form to submit. If the input is not valid, use the Set Form Element Error activity to display an error to the user and prevent the form from submitting. If the input is valid, use the Clear Form Element Error activity to clear an existing error and allow the form to submit.

If you use a Set Form Element Error activity, make sure you also use a Clear Form Element Error activity to clear the error. Otherwise the form may get stuck in an invalid state.

For an example, see Example - Subworkflow for a Validate Event.

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Documentation Version 5.11