Public bug reported: Consider this snippet of code:
----------------------------------------------- import QtQuick 2.4 import Ubuntu.Components 1.3 Item { property int bla: units.gu(10) onBlaChanged: print("bla changed", bla); property int blubb: 80 onBlubbChanged: print("blubb changed", blubb); Component.onCompleted: print("completed", bla); } ---------------------------------------------- The output of this is: qml: bla changed 80 qml: completed 80 the changed signal should not be emitted before completion, given it is its initial value and not actually changed. The current behavior triggers all the onChanged handlers when there's units.gu() involved, which results in things like change animations being played at startup and lots of wasted cpu cycles for evaluating all those changed events. ** Affects: ubuntu-ui-toolkit (Ubuntu) Importance: Undecided Status: Confirmed ** Description changed: Consider this snippet of code: ----------------------------------------------- import QtQuick 2.4 import Ubuntu.Components 1.3 Item { - property int bla: units.gu(10) - onBlaChanged: print("bla changed", bla); + property int bla: units.gu(10) + onBlaChanged: print("bla changed", bla); - property int blubb: 80 - onBlubbChanged: print("blubb changed", blubb); + property int blubb: 80 + onBlubbChanged: print("blubb changed", blubb); - Component.onCompleted: print("completed", bla); + Component.onCompleted: print("completed", bla); } ---------------------------------------------- The output of this is: qml: bla changed 80 qml: completed 80 + the changed signal should not be emitted before completion, given it is + its initial value and not actually changed. - the changed signal should not be emitted before completion, given it is its initial value and not actually changed. + The current behavior triggers all the onChanged handlers when there's + units.gu() involved, which results in things like change animations + being played at startup and lots of wasted cpu cycles for evaluating all + those changed events. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to ubuntu-ui-toolkit in Ubuntu. https://bugs.launchpad.net/bugs/1647415 Title: units.gu() emits changed signal before completion Status in ubuntu-ui-toolkit package in Ubuntu: Confirmed Bug description: Consider this snippet of code: ----------------------------------------------- import QtQuick 2.4 import Ubuntu.Components 1.3 Item { property int bla: units.gu(10) onBlaChanged: print("bla changed", bla); property int blubb: 80 onBlubbChanged: print("blubb changed", blubb); Component.onCompleted: print("completed", bla); } ---------------------------------------------- The output of this is: qml: bla changed 80 qml: completed 80 the changed signal should not be emitted before completion, given it is its initial value and not actually changed. The current behavior triggers all the onChanged handlers when there's units.gu() involved, which results in things like change animations being played at startup and lots of wasted cpu cycles for evaluating all those changed events. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ubuntu-ui-toolkit/+bug/1647415/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp