Radio Buttons

Last update: Edit

1 Introduction

The Radio Buttons widget is an input widget that can be used to display and edit Boolean and enumeration attributes.

Radio Buttons are used to display and, optionally, allow the end-user to edit the value of an attribute of data type Boolean or Enumeration.

When the page is displayed to the end-user, all the possible values are listed with a filled-in circle next to the selected value and an empty circle next to the unselected value(s). Only one value can be chosen – choosing another value deselects the current value. For example:

Radio buttons must be placed in a data widget and display an attribute of the object(s) retrieved by that widget. The name of the attribute to be displayed is shown inside the text box, between square brackets, and colored blue.

For example, the following image contains two sets of radio buttons. The first allows the end-user to see, and set, the value of an enumeration identifying the preferred time to contact this person (PreferredContact). The second allows the end-user to see, and set, a Boolean indicating whether this is a Personal contact.

2 Properties

An example of text box properties is represented in the image below:

Text box properties consist of the following sections:

2.1 Common Section

For more information on properties of this section, see the Common Section section in Properties Common for Widgets.

2.2 Data Source Section

Attribute (Path)

Many input widgets (like text boxes and drop-down widgets) can be connected to the following:

  • An attribute of the entity of the data view that contains the widget; in this case, the widget is connected to an attribute
  • An attribute of an entity associated with the data view entity by following one or more associations of the reference type through the domain model; in this case, the widget is connected to an attribute path

In the first case, we say the widget is connected to an attribute, and in the second case it is connected to an attribute path.

In Mendix 8.0, an input widget connected to an attribute path must be read-only. Studio Pro will check this for you.

In Mendix 8.1 and above, you can edit attributes presented in input widgets over a path.

2.3 Design Properties Section

2.4 Editability Section

Editability determines whether an end-user can change the value in an input widget.

For more information on properties of this section, see the Editability Section section of Properties Common for Widgets.

2.5 Events Section

2.5.1 On Change

The on-change property specifies an action that will be executed when leaving the widget, either by using the Tab key or by clicking another widget, after the value has been changed.

For more information on properties of this section, see the Event Actions section of On Click Event & Events Section.

2.5.2 On Enter

The on-enter property specifies an action that will be executed when the widget is entered, either by using the Tab key or by clicking it with the mouse.

For more information on properties of this section, see the Event Actions section of On Click Event & Events Section.

2.5.3 On Leave

The on-leave property specifies an action that will be executed when leaving the widget, either by using the Tab key or by clicking another widget.

This differs from the On change property in that the event will always be triggered, even if the value has not been changed.

For more information on properties of this section, see the Event Actions section of On Click Event & Events Section.

2.6 General Section

2.6.1 Orientation

This property defines whether the radio buttons are rendered as a Horizontal or Vertical list.

Default value: Horizontal

2.7 Label Section

A label describes the purpose of a widget to the end-user.

For more information on properties of this section, see the Label Section section in Properties Common for Widgets.

2.8 Validation Section

Validation Type

This property indicates whether this widget value should be validated and, if so, how. These are the possible options:

  • No validation
  • A predefined validation
  • A custom validation

The possible values of a predefined validation are the following:

  • Required – all data types
  • E-mail – string
  • Positive number – decimal, float, integer, long
  • Date in the future – dateTime
  • Date in the past – dateTime

Custom validations are expressions that follow the Microflow expression syntax. Both $currentObject and $value are in a scope that refers to the current object and the current member value, respectively. In Mendix 8.1 and above, the expression can access objects of all the data containers enclosing that data container widget. These objects are available under the name of the widget they originate from (for example, $dataView1).

When a validation is set and it fails for this widget, a message will be shown when the user selects Save.

Default value: (none)

Validation Message

This property determines the message that is shown to the user if widget validation is enabled and has failed. This is a translatable text (for more information, see Translatable Texts).

For example, if an address field is required, the validation message for the text box of the address could be something like, "The address is required."

2.9 Visibility Section

Visibility determines whether a widget is displayed to the end-user as part of the page.

For more information on properties of this section, see the Visibility Section section in Properties Common for Widgets.

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