Avoid discouraged patterns in examples

In particular, use required properties where applicable, explicitly
import QtQml where we use it, avoid unqualified access into the root
scope of a component, use JavaScript functions with explicit parameters
as signal handlers.

Change-Id: I3eaaba47cc3c7a2a12d488e36f9eec145cedbb0e
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>
Reviewed-by: Shawn Rutledge <shawn.rutledge@qt.io>

2 files changed, 8 insertions, 6 deletions

diff --git a/examples/quick/particles/emitters/content/burstandpulse.qml b/examples/quick/particles/emitters/content/burstandpulse.qml
index 8bd19ed8ed..d3c38c2360 100644
--- a/examples/quick/particles/emitters/content/burstandpulse.qml
+++ b/examples/quick/particles/emitters/content/burstandpulse.qml
@@ -52,6 +52,8 @@ import QtQuick 2.0
 import QtQuick.Particles 2.0
 
 Rectangle {
+    id: root
+
     width: 320
     height: 480
     color: "black"
@@ -63,12 +65,12 @@ Rectangle {
         repeat: true
         onTriggered: {
         //! [0]
-            if (lastWasPulse) {
+            if (root.lastWasPulse) {
                 burstEmitter.burst(500);
-                lastWasPulse = false;
+                root.lastWasPulse = false;
             } else {
                 pulseEmitter.pulse(500);
-                lastWasPulse = true;
+                root.lastWasPulse = true;
             }
         //! [0]
         }
diff --git a/examples/quick/particles/emitters/content/customemitter.qml b/examples/quick/particles/emitters/content/customemitter.qml
index aa8ca6b2f9..f6aea13d08 100644
--- a/examples/quick/particles/emitters/content/customemitter.qml
+++ b/examples/quick/particles/emitters/content/customemitter.qml
@@ -79,7 +79,7 @@ ParticleSystem {
         size: 12
         anchors.centerIn: parent
         //! [0]
-        onEmitParticles: {
+        onEmitParticles: (particles) => {
             for (var i=0; i<particles.length; i++) {
                 var particle = particles[i];
                 particle.startSize = Math.max(02,Math.min(492,Math.tan(particle.t/2)*24));
@@ -90,8 +90,8 @@ ParticleSystem {
                 theta /= 6.0;
                 theta *= 2.0*Math.PI;
                 theta += sys.convert(sys.petalRotation);//Convert from degrees to radians
-                particle.initialVX = petalLength * Math.cos(theta);
-                particle.initialVY = petalLength * Math.sin(theta);
+                particle.initialVX = sys.petalLength * Math.cos(theta);
+                particle.initialVY = sys.petalLength * Math.sin(theta);
                 particle.initialAX = particle.initialVX * -0.5;
                 particle.initialAY = particle.initialVY * -0.5;
             }