Softwareentwicklung in C++ - ASC

296 10. Memory – ein kleines Beispiel
72 /∗ Call t h i s method to stop the dispatcher loop . I f i t i s c a l l e d
73 ∗ from within the event handler while i t i s j u s t handling an
74 ∗ event , the loop w i l l be stopped as soon as the handler
75 ∗ n o t i f i c a t i o n method returns . I f i t i s c a l l e d from any other
76 ∗ point in the program , the dispatcher loop w i l l be stopped
77 ∗ a f t e r the next word event has been processed .
78 ∗/
79 static void stopDispatcher ( )
80 {
81 s t o p d i s p a t c h e r l o o p = true ;
82 }
83 } ;
84
85
86 #endif // s i m p l e i n p u t h a n d l i n g h
10.2.21 SimpleEventHandling
Wo Events durch die Gegend geschickt werden, braucht es auch einen Handler
dazu. Die Basisklasse dafür, von der alle Möchtegern-Event-Handler abgeleitet
sein müssen, sieht so aus:
1 // simple event handler . h − a simple a b stract event handler
2
3 #ifndef s i m p l e e v e n t h a n d l e r h
4 #define s i m p l e e v e n t h a n d l e r h
5
6 #include ” simple event . h”
7
8 //−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−
9 /∗ A simple base c l a s s . All event handlers that s h a l l be used
10 ∗ with SimpleInputHandling have to be derived from i t
11 ∗/
12
13 class EventHandler
14 {
15 public :
16
17 /∗ Destructor
18 ∗ Just to make sure that a v i r t u a l d e s t r u c t o r e x i s t s
19 ∗/
20 virtual ˜ EventHandler ( ) { }
21
22 /∗ This method i s the c a l l b a c k that i s c a l l e d f o r every s i n g l e
23 ∗ event that i s dispatched .
24 ∗ @param event The event that i s dispatched . I t can be an
25 ∗ a r b i t r a r y s u b c l a s s of Event .
26 ∗/
27 virtual void handleEvent ( const Event &event ) = 0 ;
28 } ;
29
30
31 #endif // s i m p l e e v e n t h a n d l e r h
10.2.22 MemoryGameControl
Die Klasse MemoryGameControl ist die Drehscheibe, die alles steuert, was den
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