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QML Animation not triggering on state change in Qt 6.5 with complex state conditions

👀 Views: 31 đŸ’Ŧ Answers: 1 📅 Created: 2025-06-13
Qt QML animation state management

I've encountered a strange issue with I'm working on a project and hit a roadblock. I'm working with an scenario where my QML animations are not triggering when I switch states in my application. I'm using Qt 6.5 and have defined multiple states for a `Rectangle` that contains a `Text` element. The state changes are based on some complex conditions tied to user input. However, when I change the state, the `onStateChanged` signal isn't firing as expected, and consequently, my animations are not executing. Here's a simplified version of my QML code: ```qml import QtQuick 2.15 import QtQuick.Controls 2.15 Rectangle { width: 400 height: 300 color: "lightgray" property int userValue: 0 states: [ State { name: "stateA" PropertyChanges { target: myRectangle color: "green" } }, State { name: "stateB" PropertyChanges { target: myRectangle color: "red" } } ] transitions: [ Transition { from: "stateA" to: "stateB" NumberAnimation { target: myRectangle; property: "opacity"; duration: 400; to: 0 } NumberAnimation { target: myRectangle; property: "opacity"; duration: 400; from: 0; to: 1 } } ] Rectangle { id: myRectangle width: 100 height: 100 color: "green" } Button { text: "Change State" onClicked: { userValue += 1 if (userValue % 2 == 0) { state = "stateB" } else { state = "stateA" } } } } ``` I've tried debugging the `userValue` and it seems to change correctly, but the state change does not trigger the expected animations. I also verified that the state names are correctly referenced, and everything seems in order. When I set the state directly without the conditions, the animations work fine. Any ideas on what could be going wrong here? Are there any known issues with state management in Qt 6.5 that I should be aware of that might cause this behavior? I'm using Qml 3.9 in this project. Thanks for your help in advance!