Details
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Bug
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Resolution: Unresolved
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P3: Somewhat important
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None
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5.12.0, 5.12.4, 5.13.0
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None
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Linux/X11
Description
The first button press spawns a "dummy" particle, successive presses spawn particles as expected (overridden2, ...).
It looks like QQuickItemParticle::updatePaintNode triggers a second add to m_loadables.
This results in QQuickItemParticle::tick popping the (correctly) queued item from m_pendingItems which correctly sets the d->delegate. But then the second entry from m_loadables (same d instance) is handled which overrides d->delegate with the default delegate since m_pendingItems is empty now.
I do not fully understand why the second add in updatePaintNode happens, but it seems to lead to this behaviour.
Minimal example:
import QtQuick 2.0 import QtQuick.Window 2.12 import QtQuick.Particles 2.0 import QtQuick.Controls 2.0 Window { visible: true width: 640 height: 480 title: qsTr("Hello World") Rectangle { id: root anchors.fill: parent ParticleSystem { id: particleSystem } Emitter { id: emitter system: particleSystem emitRate: 0 lifeSpan: 3000 lifeSpanVariation: 500 acceleration: AngleDirection { angle: 90 magnitude: 80 } velocity: AngleDirection { angle: -90 angleVariation: 15 magnitude: 100 magnitudeVariation: 50 } } ItemParticle { id: itemParticle system: particleSystem delegate: Text {text: "dummy"} } Component { id: component Text { text: "asdfsdfafsd" ItemParticle.onDetached: destroy(); } } Button { property int i: 0 onClicked: { let particle = component.createObject(itemParticle); particle.text = "overriden" + ++i itemParticle.take(particle) emitter.burst(1, 200, 200) } text: "spawn" } } }