SignalTransition QML Type▲
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Import Statement: import QtQml.StateMachine 1.12
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Since: Qt 5.4
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Inherits: QSignalTransition
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Group: SignalTransition is part of statemachine-qmltypes
Detailed Description▲
SignalTransition is part of The Declarative State Machine Framework.
Example Usage▲
import
QtQuick 2.0
import
QtQml.StateMachine 1.0 as
DSM
Rectangle
{
DSM.StateMachine {
id
:
stateMachine
initialState
:
state
running
:
true
DSM.State {
id
:
state
DSM.SignalTransition {
targetState
:
finalState
signal
:
button.clicked
guard
:
guardButton.checked
}
}
DSM.FinalState {
id
:
finalState
}
onFinished
:
Qt.quit()
}
Row
{
spacing
:
2
Button
{
id
:
button
text
:
"Finish state"
}
Button
{
id
:
guardButton
checkable
:
true
text
:
checked ? "Press to block the SignalTransition"
:
"Press to unblock the SignalTransition"
}
}
}
See Also▲
See also StateMachine, FinalState, TimeoutTransition
Property Documentation▲
guard : bool▲
Guard conditions affect the behavior of a state machine by enabling transitions only when they evaluate to true and disabling them when they evaluate to false.
When the signal associated with this signal transition is emitted the guard condition is evaluated. In the guard condition the arguments of the signal can be used as demonstrated in the example below.
import
QtQuick 2.0
import
QtQml.StateMachine 1.0 as
DSM
Rectangle
{
Button
{
anchors.fill
:
parent
id
:
button
DSM.StateMachine {
DSM.State {
DSM.SignalTransition {
targetState
:
finalState
signal
:
button.mysignal
// the guard condition uses the mystr string argument from mysignal
guard
:
mystr ==
"test"
}
}
DSM.FinalState {
id
:
finalState
}
}
// define the signal the SignalTransition is connected with
signal mysignal(string
mystr)
// on clicking the button emit the signal with a single string argument
onClicked
:
button.mysignal("test"
)
}
}
See Also▲
See also signal
signal : signal▲
The signal which is associated with this signal transition.
import
QtQuick 2.0
import
QtQml.StateMachine 1.0 as
DSM
Rectangle
{
Button
{
anchors.fill
:
parent
id
:
button
DSM.StateMachine {
DSM.State {
DSM.SignalTransition {
targetState
:
finalState
signal
:
button.clicked
}
}
DSM.FinalState {
id
:
finalState
}
}
}
}