Listening for scrollbar events using Symbian C++

Article Metadata

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Code Example

Source file: Media:CustomControl.zip

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Platform Security

Signing Required: Self-Signed

Capabilities: None

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Article

Keywords: MEikScrollBarObserver, MEikScrollBarObserver::HandleScrollEventL()

Created: tapiolaitinen (01 Apr 2008)

Last edited: hamishwillee (06 Aug 2012)

Overview

This snippet demonstrates how to listen for scrollbar events.

Note: MEikScrollBarObserver::HandleScrollEventL() used in this snippet requires Touch UI support.

MMP file

The following libraries are required:

LIBRARY eikcoctl.lib

Header file

#include <coecntrl.h>  // CCoeControl
#include <eiksbobs.h>  // MEikScrollBarObserver
 
class CMyContainer : public CCoeControl, public MEikScrollBarObserver
    {
    // ...
 
    private:  // Functions from base classes
        /**
         * From MEikScrollBarObserver.
         */
        void HandleScrollEventL(CEikScrollBar* aScrollBar,
                TEikScrollEvent aEventType);
    };

Source file

#include <eiksbfrm.h>  // CEikScrollBarFrame

/**
 * From MEikScrollBarObserver.
 */
void CMyContainer::HandleScrollEventL(CEikScrollBar* aScrollBar,
        TEikScrollEvent aEventType)
    {
    if (!aScrollBar)
        {
        return;
        }
 
    switch (aEventType)
        {
        case EEikScrollLeft:
            {
            // Moving left one step
            break;
            }
        case EEikScrollRight:
            {
            // Moving right one step
            break;
            }
 
        case EEikScrollUp:
            {
            // Moving up one step
            break;
            }
        case EEikScrollDown:
            {
            // Moving down one step
            break;
            }
 
        case EEikScrollPageLeft:
            {
            // Moving left one page
            break;
            }
        case EEikScrollPageRight:
            {
            // Moving right one page
            break;
            }
 
        case EEikScrollPageUp:
            {
            // Moving up one page
            break;
            }
        case EEikScrollPageDown:
            {
            // Moving down one page
            break;
            }
 
        case EEikScrollThumbDragHoriz:
            {
            // Horizontal drag started
            break;
            }
        case EEikScrollThumbReleaseHoriz:
            {
            // Horizontal drag released
            break;
            }
 
        case EEikScrollThumbDragVert:
            {
            // Vertical drag started
            break;
            }
        case EEikScrollThumbReleaseVert:
            {
            // Vertical drag released
            break;
            }
 
        case EEikScrollHome:
            {
            // Scrolled to the beginning (horiz.)
            break;
            }
        case EEikScrollEnd:
            {
            // Scrolled to the end (horiz.)
            break;
            }
 
        case EEikScrollTop:
            {
            // Scrolled to the top (vert.)
            break;
            }
        case EEikScrollBottom:
            {
            // Scrolled to the bottom (vert.)
            break;
            }
 
        default:
            {
            break;
            }
        }
    }

Postconditions

The application listens for scrollbar events.

See also

For information about implementing scrollbars, see File:CustomControl.zip.