I have four fields with repeating buttons used to add/subtract one from the
total. This is done in the function below. However, I am running into an
error :" just wrote to memory location xxx, which is in Memory Manager data
struct". Seems like I am overrunning my pointer. I thought I was keeping up
with the size of the pointer based on the number of digits in the field.
What am I doing wrong??
(Note: I am new to C and Palm. Not sure where my mistake is)
static void IncrementFormField(UInt16 fieldID, UInt8 numAction)
{
FormPtr frmP = FrmGetActiveForm();
FieldType *fldP;
MemHandle handle;
char *str;
UInt8 number;
fldP = (FieldType *)FrmGetObjectPtr(frmP,FrmGetObjectIndex(frmP, fieldID));
handle = FldGetTextHandle(fldP);
if (handle)
{
FldSetTextHandle(fldP, NULL);
str = MemHandleLock(handle);
number = StrAToI(str);
// Increment or decrement
if (numAction == Increment)
number += 1;
else
if (number > 0)
number -= 1;
// Resize pointer to minimum needed
if (number > 99)
MemPtrResize(str, 3);
else
if (number > 9)
MemPtrResize(str, 2);
//else
//MemPtrResize(str, 1);
StrIToA(str,number);
SetFieldTextFromPtr(fieldID, str);
}
// Code to create new handle if not found . . .
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