Mutually-exclusive group of checkable buttons. 更多...
导入语句: | import QtQuick.Controls 2.5 |
Since: | Qt 5.7 |
继承: |
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 或 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()
方法。
另请参阅 RadioButton and 按钮控件 .
[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") } }
另请参阅 group .
checkState : enumeration |
This property holds the combined check state of the button group.
Available states:
常量 | 描述 |
---|---|
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
被忽略。
Setting the check state of an exclusive button group to
Qt.Unchecked
unchecks the
checkedButton
.
Qt.Checked
and
Qt.PartiallyChecked
被忽略。
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.
另请参阅 exclusive .
exclusive : bool |
This property holds whether the button group is exclusive. The default value is
true
.
若此特性为
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
特性为
null
.
该特性在 QtQuick.Controls 2.3 (Qt 5.10) 引入。
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 }
另请参阅 buttons .
clicked ( AbstractButton 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" } }
该信号在 QtQuick.Controls 2.1 (Qt 5.8) 引入。
另请参阅 AbstractButton::clicked() .
void addButton ( AbstractButton button ) |
Adds a button to the button group.
注意: Manually adding objects to a button group is typically unnecessary. The buttons property and the group attached property provide a convenient and declarative syntax.
void removeButton ( AbstractButton button ) |
Removes a button 从按钮组。
注意: Manually removing objects from a button group is typically unnecessary. The buttons property and the group attached property provide a convenient and declarative syntax.