ButtonGroup QML Type | Qt Quick Controls 5.14.1

Qt 5.14 | Qt Quick Controls | QML Types | ButtonGroup QML Type

Qt 5.14.1 Reference Documentation

# ButtonGroup QML Type

Mutually-exclusive group of checkable buttons. More...

Import Statement: | import QtQuick.Controls 2.14
Since: | Qt 5.7
Inherits: | QtObject

- List of all members, including inherited members

## Properties

- buttons : list<AbstractButton>
- checkState : enumeration
- checkedButton : AbstractButton
- exclusive : bool

## Attached Properties

- group : ButtonGroup

## Signals

- clicked(button)

## Methods

- void addButton(button)
- void removeButton(button)

## Detailed Description

ButtonGroup is a non-visual, mutually exclusive group of buttons. It is used with controls such as RadioButton, where only one of the options can be selected at a time.

The most straight-forward way to use ButtonGroup is to assign a list of buttons. For example, the list of children of a positioner or a layout that manages a group of mutually exclusive buttons.

      ButtonGroup {
          buttons: column.children
      }

      Column {
          id: column

          RadioButton {
              checked: true
              text: qsTr("DAB")
          }

          RadioButton {
              text: qsTr("FM")
          }

          RadioButton {
              text: qsTr("AM")
          }
      }

Mutually exclusive buttons do not always share the same parent item, or the parent layout may sometimes contain items that should not be included in the button group. Such cases are best handled using the group attached property.

      ButtonGroup { id: radioGroup }

      Column {
          Label {
              text: qsTr("Radio:")
          }

          RadioButton {
              checked: true
              text: qsTr("DAB")
              ButtonGroup.group: radioGroup
          }

          RadioButton {
              text: qsTr("FM")
              ButtonGroup.group: radioGroup
          }

          RadioButton {
              text: qsTr("AM")
              ButtonGroup.group: radioGroup
          }
      }

More advanced use cases can be handled using the `addButton()` and `removeButton()` methods.

See also RadioButton and Button Controls.

## Property Documentation

[default] buttons : list<AbstractButton>

This property holds the list of buttons.

      ButtonGroup {
          buttons: column.children
      }

      Column {
          id: column

          RadioButton {
              checked: true
              text: qsTr("Option A")
          }

          RadioButton {
              text: qsTr("Option B")
          }
      }

See also group.

checkState : enumeration

This property holds the combined check state of the button group.

Available states:

Constant | Description
--- | ---
`Qt.Unchecked` | None of the buttons are checked.
`Qt.PartiallyChecked` | Some of the buttons are checked.
`Qt.Checked` | All of the buttons are checked.

Setting the check state of a non-exclusive button group to `Qt.Unchecked` or `Qt.Checked` unchecks or checks all buttons in the group, respectively. `Qt.PartiallyChecked` is ignored.

Setting the check state of an exclusive button group to `Qt.Unchecked` unchecks the checkedButton. `Qt.Checked` and `Qt.PartiallyChecked` are ignored.

This property was introduced in QtQuick.Controls 2.4 (Qt 5.11).

checkedButton : AbstractButton

This property holds the currently selected button in an exclusive group, or `null` if there is none or the group is non-exclusive.

By default, it is the first checked button added to an exclusive button group.

See also exclusive.

exclusive : bool

This property holds whether the button group is exclusive. The default value is `true`.

If this property is `true`, then only one button in the group can be checked at any given time. The user can click on any button to check it, and that button will replace the existing one as the checked button in the group.

In an exclusive group, the user cannot uncheck the currently checked button by clicking on it; instead, another button in the group must be clicked to set the new checked button for that group.

In a non-exclusive group, checking and unchecking buttons does not affect the other buttons in the group. Furthermore, the value of the checkedButton property is `null`.

This property was introduced in QtQuick.Controls 2.3 (Qt 5.10).

## Attached Property Documentation

ButtonGroup.group : ButtonGroup

This property attaches a button to a button group.

      ButtonGroup { id: group }

      RadioButton {
          checked: true
          text: qsTr("Option A")
          ButtonGroup.group: group
      }

      RadioButton {
          text: qsTr("Option B")
          ButtonGroup.group: group
      }

See also buttons.

## Signal Documentation

clicked(button)

This signal is emitted when a button in the group has been clicked.

This signal is convenient for implementing a common signal handler for all buttons in the same group.

      ButtonGroup {
          buttons: column.children
          onClicked: console.log("clicked:", button.text)
      }

      Column {
          id: column
          Button { text: "First" }
          Button { text: "Second" }
          Button { text: "Third" }
      }

This signal was introduced in QtQuick.Controls 2.1 (Qt 5.8).

See also AbstractButton::clicked().

## Method Documentation

void addButton(button)

Adds a button to the button group.

Note: Manually adding objects to a button group is typically unnecessary. The buttons property and the group attached property provide a convenient and declarative syntax.

See also buttons and group.

void removeButton(button)

Removes a button from the button group.

Note: Manually removing objects from a button group is typically unnecessary. The buttons property and the group attached property provide a convenient and declarative syntax.

See also buttons and group.