Programming Visual Basic for the Palm OS

Debug Database

The previous debugging techniques involve POSE and the Palm Reporter. In this section, we show how to send debug information to a database on POSE or the Palm handheld. This technique is especially useful for debugging applications where the Reporter may not or cannot be used.

We encapsulate debug functionality in a module called modDebugDB, which can be accessed by other components in our application. This module contains four functions for logging messages to a database.

DebugDatabase

This public subroutine logs a message to the debug database.

OpenDebugDatabase

This private subroutine creates the debug database, if necessary, and opens it.

WriteDebugRecord

This private function writes a record to the debug database.

DeleteDebugDatabase

This public subroutine deletes the debug database.

PalmIDtoLong(PalmID As String) As Long

This private helper function converts a Palm ID String to a Long. It is copied from the PDBTutorial project that comes with AppForge. We do not discuss this function in this chapter.

We begin the module by declaring variables for a database handle and record type.

Option Explicit

' Use this global to store the database handle
Private dbDebug As Long

Public Type tDebugRecord
        Message As String
End Type

Here, we simply store a message String in each record. This is the listing for DebugDatabase.

Public Sub DebugDatabase(msg As String) Dim debugRecord As tDebugRecord OpenDebugDatabase If dbDebug <> 0 Then 'We successfully opened the database ...