Categories: Symbian C++ | Code Examples | Files/Data

This page was last modified 09:58, 3 July 2008.

From Forum Nokia Wiki

Knowledge Base Home

Overview

This code snippet shows how to create a global message query CAknGlobalMsgQuery. A global message query is constructed by calling the NewL() method and is executed using the ShowMsgQueryL() method. An active object has to be constructed to handle the dismissal of the dialog. This example uses the generic class CGlobalQueryHandlerAO that is also used with other global query code snippets. The class CGlobalQueryContainer is used to launch the query and it is also the observer that implements the interface MGlobalQueryObserver.

This snippet can be self-signed.

MMP file

The following libraries are required:

LIBRARY     cone.lib            //CEikonEnv, CCoeEnv 
LIBRARY     avkon.lib           //Avkon resources
LIBRARY     CommonEngine.lib    //StringLoader 
LIBRARY     euser.lib           //CActive, CleanupStack

Resource file

.rss

#include <eikon.rh>
#include <avkon.rsg>
#include <avkon.rh>
 
//...
RESOURCE TBUF r_global_query_header_text
    {   
    buf = "<header text here>"; 
    }
 
RESOURCE TBUF r_global_query_message_text
    {   
    buf = "<message text here>"; 
    }

Header files

• observer interface

#ifndef GLOBALQUERYOBSERVER_H
#define GLOBALQUERYOBSERVER_H
 
class MGlobalQueryObserver
    {
public:     
    //keep these methods short running because they are called
    //from within an active object  
    virtual void ProcessOkOptionL() = 0;
    virtual void ProcessCancelOptionL() = 0;
    virtual void ProcessDoneOptionL() = 0;
    virtual void ProcessSelectedItemL(const TInt aItem) = 0;
    };
 
#endif  // GLOBALQUERYOBSERVER_H

• handler active object

#ifndef GLOBALQUERYHANDLERAO_H
#define GLOBALQUERYHANDLERAO_H
 
#include <e32base.h>  //CActive
#include "GlobalQueryObserver.h"
 
class CGlobalQueryHandlerAO : public CActive
    {
public:
    ~CGlobalQueryHandlerAO();
    static CGlobalQueryHandlerAO* NewL(MGlobalQueryObserver& aObserver);
    static CGlobalQueryHandlerAO* NewLC(MGlobalQueryObserver& aObserver);   
public: 
    void StartHandler();    
private:    
    CGlobalQueryHandlerAO(MGlobalQueryObserver& aObserver) 
            : CActive (EPriorityStandard), iObserver(aObserver){};
    void ConstructL();  
private: // from CActive    
    void RunL();
    void DoCancel();
private: // data
    MGlobalQueryObserver& iObserver;
    };
#endif //GLOBALQUERYHANDLERAO_H

• container / observer

#ifndef GLOBALQUERYCONTAINER_H
#define GLOBALQUERYCONTAINER_H
 
#include <coecntrl.h> // CCoeControl
#include "GlobalQueryObserver.h"
#include <aknglobalmsgquery.h> //CAknGlobalMsgQuery
class CGlobalQueryHandlerAO;
 
class CGlobalQueryContainer : public CCoeControl, MGlobalQueryObserver
    {
public:
//...
void MakeExampleQueryL();
public: // from MGlobalQueryObserver
    void ProcessOkOptionL();
    void ProcessCancelOptionL();
    void ProcessDoneOptionL(); //not used
    void ProcessSelectedItemL(const TInt aItem); //not used
//...
private:
    CGlobalQueryHandlerAO*       iQueryHandlerAO;
    CAknGlobalMsgQuery*          iGlobalMsgQuery;
    };
#endif  // GLOBALQUERYCONTAINER_H

Source files

• handler active object

#include "GlobalQueryHandlerAO.h"
#include <avkon.hrh> //EAknSoftkeyOk, EAknSoftkeyCancel, EAknSoftkeyDone
 
CGlobalQueryHandlerAO::~CGlobalQueryHandlerAO() { Cancel(); }
 
void CGlobalQueryHandlerAO::ConstructL()
    {
    CActiveScheduler::Add(this);
    }
 
CGlobalQueryHandlerAO* CGlobalQueryHandlerAO::NewLC(MGlobalQueryObserver& aObserver)
    {
    CGlobalQueryHandlerAO* self = new (ELeave) CGlobalQueryHandlerAO(aObserver);
    CleanupStack::PushL(self);
    self->ConstructL();
    return self;
    }
 
CGlobalQueryHandlerAO* CGlobalQueryHandlerAO::NewL(MGlobalQueryObserver& aObserver)
    {
    CGlobalQueryHandlerAO* self = CGlobalQueryHandlerAO::NewLC(aObserver);
    CleanupStack::Pop(self);
    return self;
    }
 
void CGlobalQueryHandlerAO::DoCancel(){}
 
void CGlobalQueryHandlerAO::StartHandler() { SetActive(); }
 
void CGlobalQueryHandlerAO::RunL()
    {
    if (iStatus == EAknSoftkeyOk)
        iObserver.ProcessOkOptionL();
    else if(iStatus == EAknSoftkeyCancel)
        iObserver.ProcessCancelOptionL();
    else if(iStatus == EAknSoftkeyDone)
        iObserver.ProcessDoneOptionL();
    else
        iObserver.ProcessSelectedItemL(iStatus.Int());
        
    Cancel();
    }

• container / observer

#include "GlobalQueryContainer.h" //CGlobalQueryContainer
#include "GlobalQueryHandlerAO.h" //CGlobalQueryHandlerAO
#include <GlobalQuery_0xED0C36BE.rsg> //Resources
#include <StringLoader.h> // StringLoader
 
void CGlobalQueryContainer::ConstructL(const TRect& aRect)
    {
    CreateWindowL();
    SetRect(aRect);
    ActivateL();
    
    MakeExampleQueryL();
    }
 
void CGlobalQueryContainer::MakeExampleQueryL()
    {   
    //start the query handler and show global message query
    iQueryHandlerAO = CGlobalQueryHandlerAO::NewL(*this);
    iQueryHandlerAO->StartHandler();
 
    iGlobalMsgQuery = CAknGlobalMsgQuery::NewL();
    HBufC* headerText = StringLoader::LoadLC(R_GLOBAL_QUERY_HEADER_TEXT);
    HBufC* messageText = StringLoader::LoadLC(R_GLOBAL_QUERY_MESSAGE_TEXT);
 
    //show the global message query 
    iGlobalMsgQuery->ShowMsgQueryL(iQueryHandlerAO->iStatus,
                                    *messageText, 
                                    R_AVKON_SOFTKEYS_OK_CANCEL,
                                    *headerText,
                                    KNullDesC);
    
    CleanupStack::PopAndDestroy(2); //messageText, headerText   
    }
 
CGlobalQueryContainer::~CGlobalQueryContainer()
    {
    //...
    delete iQueryHandlerAO;
    delete iGlobalMsgQuery;
    }
 
void CGlobalQueryContainer::ProcessOkOptionL()
    {
    //OK pressed, do something
    iEikonEnv->InfoWinL(_L("OK"),_L("Pressed"));
    }
void CGlobalQueryContainer::ProcessCancelOptionL()
    {
    //Cancel pressed, do something...
    iEikonEnv->InfoWinL(_L("Cancel"),_L("Pressed"));
    }
void CGlobalQueryContainer::ProcessDoneOptionL()
    {
    //not used
    }
void CGlobalQueryContainer::ProcessSelectedItemL(const TInt /*aItem*/)
    {   
    //not used
    }

Postconditions

The example code shows how to create a global message query, handle its dismissal, and how the active object handler informs an observer class that the dialog has been closed.

See also

• CS001060 - Showing a global confirmation query using CAknGlobalConfirmationQuery
• CS001061 - Showing a global list query using CAknGlobalListQuery
• CS001062 - Showing a global progress dialog using CAknGlobalProgressDialog