QQuick3DParticleEmitter:: Fix nullptr connect

When setting the particle for the first time m_particle is nullptr so
the depthBiasChanged signal is connected to a nullptr object. This
commit moves the connect so it only connect to non-nullptr particles.

Pick-to: 6.5
Change-Id: Ief4e6a2cbc07b7bbce9b87e4668689f5ad8f61d1
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Antti Määttä <antti.maatta@qt.io>
(cherry picked from commit 551f4a84a79cc7c4beaeef0f65b5773b38acff38)
Reviewed-by: Jonas Karlsson <jonas.karlsson@qt.io>

1 files changed, 3 insertions, 3 deletions

diff --git a/src/quick3dparticles/qquick3dparticleemitter.cpp b/src/quick3dparticles/qquick3dparticleemitter.cpp
index ccf0d1f8..396aec39 100644
--- a/src/quick3dparticles/qquick3dparticleemitter.cpp
+++ b/src/quick3dparticles/qquick3dparticleemitter.cpp
@@ -361,15 +361,15 @@ void QQuick3DParticleEmitter::setParticle(QQuick3DParticle *particle)
         return;
     }
 
-    QObject::connect(this, &QQuick3DParticleEmitter::depthBiasChanged, [this](){
-        m_particle->setDepthBias(m_depthBias);
-    });
     if (m_particle && m_system && !m_system->isShared(m_particle))
         m_particle->setSystem(nullptr);
     m_particle = particle;
     if (particle) {
         particle->setDepthBias(m_depthBias);
         particle->setSystem(system());
+        QObject::connect(this, &QQuick3DParticleEmitter::depthBiasChanged, m_particle, [this]() {
+            m_particle->setDepthBias(m_depthBias);
+        });
     }
     Q_EMIT particleChanged();
 }