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ID	TSS000199	Creation date	April 7, 2005, updated October 14, 2008
Platform	S60 (all)	Devices
Category	Symbian C++	Subcategory	UI, UI Components

Keywords (APIs, classes, methods, functions):

Overview

Menu item command IDs and dialog item ID values of 0 will cause problems which may be hard to identify and debug.

Detailed description

Menu item (RESOURCE MENU_ITEM) command IDs and dialog item (RESOURCE DLG_LINE) will cause problems which may be hard to identify and debug if 0 is used as the ID value.

Solution

Always use a non-zero value for MENU_ITEM command IDs, because 0 is reserved for the EEikCmdCanceled command.

Similarly, a dialog's item (DLG_LINE) IDs must be non-zero. Dialog items with a zero ID will result in "Eikon-Dialog 3" panic, where 3 is listed as EEikDialogPanicFocusableLineWithIdZero.

Typically, applications define resource ID values as enumerations and a common mistake is to begin the enumeration from 0 (default), which leads to these hard-to-identify problems.