Make component.createObject require a parent argument

For graphical objects (the common case) a common mistake is to not
parent a dynamically created item. Since you almost always want to add a
parent, and it's hard for a beginner to diagnose this problem, a parent
is now a required argument and dealt with by the createObject function.

Task-number: QTBUG-10110

2 files changed, 3 insertions, 6 deletions

diff --git a/demos/declarative/samegame/SamegameCore/samegame.js b/demos/declarative/samegame/SamegameCore/samegame.js
index cc0a70d..f9c6184 100755
--- a/demos/declarative/samegame/SamegameCore/samegame.js
+++ b/demos/declarative/samegame/SamegameCore/samegame.js
@@ -176,14 +176,13 @@ function createBlock(column,row){
     // not be ready immediately. There is a statusChanged signal on the
     // component you could use if you want to wait to load remote files.
     if(component.status == Component.Ready){
-        var dynamicObject = component.createObject();
+        var dynamicObject = component.createObject(gameCanvas);
         if(dynamicObject == null){
             console.log("error creating block");
             console.log(component.errorsString());
             return false;
         }
         dynamicObject.type = Math.floor(Math.random() * 3);
-        dynamicObject.parent = gameCanvas;
         dynamicObject.x = column*gameCanvas.blockSize;
         dynamicObject.targetX = column*gameCanvas.blockSize;
         dynamicObject.targetY = row*gameCanvas.blockSize;
diff --git a/demos/declarative/snake/content/snake.js b/demos/declarative/snake/content/snake.js
index 102bd87..f5c231e 100644
--- a/demos/declarative/snake/content/snake.js
+++ b/demos/declarative/snake/content/snake.js
@@ -59,8 +59,7 @@ function startNewGame()
                     console.log("Still loading linkComponent");
                 continue;//TODO: Better error handling?
             }
-            var link = linkComponent.createObject();
-            link.parent = playfield;
+            var link = linkComponent.createObject(playfield);
             link.z = numRows * numColumns + 1 - i;
             link.type = i == 0 ? 2 : 0;
             link.spawned = false;
@@ -300,8 +299,7 @@ function createCookie(value) {
             console.log("Still loading cookieComponent");
         return;//TODO: Better error handling?
     }
-    cookie = cookieComponent.createObject();
-    cookie.parent = head.parent;
+    cookie = cookieComponent.createObject(head.parent);
     cookie.value = value;
     cookie.row = row;
     cookie.column = column;