Creating resource header files

Typically when you create an application, there are cases where you need to create an enumerated set of command IDs (which are symbols with integer values). These defined symbols can then be used in both your code and resource files. Common examples of these cases, include:

• Custom command IDs used for mapping mobile device user input based upon Options menu selections to command handling. These custom command IDs are mapped to the text displayed for the command in the Options menu in resource files, and then are passed back to the application by the application framework.

• Control IDs in dialogs to allow references to the dialog controls from C++ code.

  For more information on control IDs for dialogs, see Using Dialogs API.

• Application view IDs. Note that these could also be enumerated in the header files for the views.

• IDs for other resource structures, such as for TABS in the status pane.

These enumerated values need to be defined in a resource file, which by convention has the extension hrh, The syntax is as follows:

enum TCommandIds
    {
    ECmdAppTest1 = 1,
    ECmdView1Cmd1,
    ECmdView1Cmd2,
    ECmdView1Cmd3,
    ECmdView2Cmd1,
    ECmdView2Cmd2,
    ECmdView2Cmd3,
    ECmdView2Cmd4
    };

where

• enum is the keyword declaration the set of integer values. Note that you would use this keyword for each set of enumerated values you defined.

• TCommandIds is a label for the list of enumerated values. This label is not used in the code or resource files.

• ECmdAppTest1 is a symbol that can be used in your code or resource files

• = is the operator used for setting the value to the symbol

• 1 is the specific value assigned to the enumerator symbol

Each enumerator is followed by a ,, except for the last value. It is recommended to have a final ; after the enumerated list. If a specific value is not assigned to a symbol in the enumerated list, then the value is that of the previous enumerator plus one. Thus, the value for ECmdView1Cmd1 above is 2.

For more information about the use of the enum statement, see ENUM statement in the Symbian OS Library.