QMetaType/Doc: update some wording about type registration

Type registration isn't necessary any more, unless you're trying to look
up a name back to ID or QMetaType object. It hasn't been since 6.0.

Drive-by update the example not to use deprecated API.

Drive-by remove the paragraph about requirements that aren't accurate
any more.

Pick-to: 6.4
Task-number: QTBUG-104858
Change-Id: Ic6547f8247454b47baa8fffd170eecb66719fa65
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>

1 files changed, 5 insertions, 5 deletions

diff --git a/src/corelib/doc/snippets/code/src_corelib_kernel_qmetatype.cpp b/src/corelib/doc/snippets/code/src_corelib_kernel_qmetatype.cpp
index b66951357d..a213ccbca6 100644
--- a/src/corelib/doc/snippets/code/src_corelib_kernel_qmetatype.cpp
+++ b/src/corelib/doc/snippets/code/src_corelib_kernel_qmetatype.cpp
@@ -35,12 +35,12 @@ MyStruct s2 = var.value<MyStruct>();
 
 
 //! [3]
-int id = QMetaType::type("MyClass");
-if (id != QMetaType::UnknownType) {
-    void *myClassPtr = QMetaType::create(id);
+QMetaType type = QMetaType::fromName("MyClass");
+if (type.isValid()) {
+    void *myClassPtr = type.create();
     ...
-    QMetaType::destroy(id, myClassPtr);
-    myClassPtr = 0;
+    type.destroy(myClassPtr);
+    myClassPtr = nullptr;
 }
 //! [3]