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--- qt:heap_versus_stack [2010/12/08 22:12] – [Short answer] mithat
+++ qt:heap_versus_stack [2010/12/08 22:22] – [Heap or Stack?] mithat
@@ Line 1: / Line 1: @@
 ====== Heap or Stack? ======
-Should Qt objects be created on the heap or on the stack?((Reminder: the heap is the memory store from which dynamically allocated storage is taken; the stack is used for standard variable storage as well as for passing values to functions, etc.))
+Should Qt objects be created on the heap or on the stack?((Reminder: the heap is the memory store from which dynamically allocated storage is taken; the stack is used for standard variable storage as well as for passing actual parameters to functions, etc.))
 ===== Short answer =====
@@ Line 14: / Line 14: @@
 For this to work, there are two requirements:
-  - All child objects must be created on the heap; however, the root itself may be on the stack. In other words, child objects that you intend to place in the tree must be created dynamically (using ''new'').
+  - All child objects must be created on the heap; however, the root itself may be on the stack. In other words, child objects that you intend to place in the tree must be created dynamically using the ''new'' operator.
   - Child objects must explicitly be made children of their parents (i.e., they must be //reparented//). Constructors for (re)parentable Qt objects let you pass parameters to specify the parent.
@@ Line 20: / Line 20: @@
 <code cpp-qt>
 QObjectSubclass theParent;                              // create theParent on the stack
+AnotherQObjectSubclass *foo;                            // pointer to a child
-AnotherQObjectSubclass *foo;
+foo = new AnotherQObjectSubclass( "bar", &theParent );  // create foo on the heap and reparent to theParent
-foo = new AnotherQObjectSubclass( "foo", &theParent );  // create foo on the heap and reparent to theParent
 </code>