TB10.1 Example Applications: examples/Base/MemMan/Cleanup/NewL/NewL.cpp Source File

00001 // Copyright (c) 2000-2009 Nokia Corporation and/or its subsidiary(-ies).
-00002 // All rights reserved.
-00003 // This component and the accompanying materials are made available
-00004 // under the terms of "Eclipse Public License v1.0"
-00005 // which accompanies this distribution, and is available
-00006 // at the URL "http://www.eclipse.org/legal/epl-v10.html".
-00007 //
-00008 // Initial Contributors:
-00009 // Nokia Corporation - initial contribution.
-00010 //
-00011 // Contributors:
-00012 //
-00013 // Description:
-00014 // NOTE: the structure of this example is different to standard E32 examples
-00015 //
-00016 
-00017 #include <e32cons.h>
-00018 
-00019   // All messages written to this
-00020 LOCAL_D CConsoleBase* console;
-00021   
-00022   // Flag which determines whether the doSomething() member function
-00023   // of the CExample class should leave when called.
-00024 LOCAL_D TBool leaveFlag = ETrue;
-00025 
-00026   // Parameter for __UHEAP_SETFAIL
-00027   // Allocation guaranteed to fail at this number of allocation attempts;
-00028   // i.e. if set to n, allocation fails on the nth attempt. 
-00029   // NB only used in debug mode
-00030 #ifdef _DEBUG
-00031 LOCAL_D TInt allocFailNumber = 1;
-00032 #endif
-00033   
-00034   // Function prototypes
-00035 LOCAL_C void doExampleL();      
-00036 LOCAL_C void callExampleL();
-00037 
-00038 
-00039 
-00041 //
-00042 // -----> CExample (definition)
-00043 //
-00044 // The class is used by the example code
-00045 //
-00047 class CExample : public CBase
-00048         {
-00049 public :
-00050         static CExample* NewL(TInt aVal);
-00051         void DoSomethingL();
-00052 public :
-00053         TInt iInt;
-00054         };
-00055 
-00056 
-00058 //
-00059 // -----> CExample (implementation)
-00060 //
-00062 CExample* CExample::NewL(TInt aVal)
-00063         {
-00064         CExample* self = new (ELeave) CExample;
-00065         self->iInt = aVal;
-00066         return self;
-00067         }
-00068 
-00069 
-00070 void CExample::DoSomethingL() 
-00071         {
-00072           // Leave if the global flag is set
-00073         if (leaveFlag)
-00074                 {
-00075                 _LIT(KMsgLeaving,"DoSomethingL leaving.\n");
-00076                 console->Printf(KMsgLeaving);
-00077                 User::Leave(KErrGeneral);               
-00078                 }
-00079         _LIT(KFormat1,"Value of iInt is %d.\n");
-00080         console->Printf(KFormat1,iInt);
-00081         }
-00082 
-00084 //
-00085 // Main function called by E32
-00086 //
-00088 GLDEF_C TInt E32Main()
-00089     {
-00090           // Get cleanup stack
-00091         CTrapCleanup* cleanup=CTrapCleanup::New();
-00092 
-00093           // Some more initialization, then do the example
-00094         TRAPD(error,callExampleL());
-00095           
-00096           // callExampleL() should never leave.
-00097         _LIT(KMsgPanicEpoc32ex,"EPOC32EX");
-00098         __ASSERT_ALWAYS(!error,User::Panic(KMsgPanicEpoc32ex,error));
-00099 
-00100           // destroy the cleanup stack
-00101         delete cleanup;
-00102         
-00103           // return
-00104         return 0;
-00105     }
-00106 
-00107 
-00109 //
-00110 //
-00111 //
-00113 LOCAL_C void callExampleL() 
-00114     {
-00115           // Initialize and call the example code under cleanup stack.
-00116         _LIT(KMsgExampleCode,"Symbian platform Example Code");
-00117         console = Console::NewL(KMsgExampleCode,TSize(KConsFullScreen,KConsFullScreen));
-00118           // Put console onto the cleanup stack.
-00119         CleanupStack::PushL(console);
-00120 
-00121           // Perform the example function under the protection of a 
-00122           // TRAP harness.
-00123         TRAPD(error,doExampleL());
-00124         _LIT(KMsgOK,"ok");
-00125         _LIT(KFormat2,"failed: leave code = %d");
-00126         if (error)
-00127                 console->Printf(KFormat2,error);
-00128         else
-00129                 console->Printf(KMsgOK);
-00130           
-00131           // Continue
-00132         _LIT(KMsgPressAnyKey," [press any key]");
-00133         console->Printf(KMsgPressAnyKey);
-00134         console->Getch();
-00135 
-00136           // Remove the console object from the cleanupstack
-00137           // and destroy it. 
-00138         CleanupStack::PopAndDestroy();
-00139     }
-00140 
-00141 
-00143 //
-00144 // Do the example
-00145 //
-00146 // Example includes a NewL() function of the CExample class which may leave
-00147 //
-00149 void doExampleL()
-00150         {
-00151           // Memory alloc fails on the 'allocFailNumber' attempt. 
-00152         __UHEAP_SETFAIL(RHeap::EDeterministic,allocFailNumber);
-00153           // Allocate - leave if allocation fails.
-00154         CExample* myExample = CExample::NewL(5);
-00155           // Push onto the cleanup stack, if successful
-00156         CleanupStack::PushL(myExample);
-00157           // Do something that can leave.
-00158         myExample->DoSomethingL();
-00159           // Pop from the cleanup stack and destroy
-00160         CleanupStack::PopAndDestroy();
-00161         }
-00162 
-00163 
-00164 
-00165 
-00166 
-00167 
-00168 
-00169 
-