I've had problems passing parameters to applications via SysAppLaunch
because the PalmOS was deallocating the parameter block upon exit from
the caller application. Try this code for the caller application:testtype
*returnvp;
Err err;
LocalID dbID;
dbID = DmFindDatabase(0, "Application");
returnvp = MemPtrNew (sizeof(testtype));
MemPtrSetOwner(test, 0); // Set the owner to be the PalmOS
if (dbID) {
err = SysAppLaunch (0, dbID, 0, 32768, 0, (DWord *) test);
}
Keep in mind that, when changing the owner, you are preventing PalmOS
from deallocating test. Don't forget to do it yourself somewhere,
or you'll have a serious memory leak - because it survives past the end
of the application.
Chris DiPierro wrote:
I've successfully used SysAppLaunch and customized
launch codes to pass
DWords back and forth, but I'm having a few conceptual problems getting
my
mind around how to make it work to pass structures around.
For instance, if I have:
typedef struct
{
Char name[40];
Int value;
} testtype;
I can do something like this in the calling application:
testtype *returnvp;
Err err;
LocalID dbID;
dbID = DmFindDatabase(0, "Application");
returnvp = MemPtrNew (sizeof(testtype));
if (dbID) {
err = SysAppLaunch (0, dbID, 0, 32768, 0, (DWord *) test);
}
And something like this in the returning app:
testtype *test;
if (cmd == 32768) {
test = MemPtrNew (sizeof(testtype));
StrCopy (test->name, "Bob");
test->value = 5;
return ((DWord)test);
}
While it builds fine, and I can test that the app launches fine (I can
put a
WinDrawChars in the above code), I can't get the correct values out
of the
app that launches this. However, if I simply use DWord's instead, all
works
fine...Obviously I'm doing something silly, can someone point it out
to me.
Thanks.
--
Sergio Carvalho
---------------
[EMAIL PROTECTED]
If at first you don't succeed, skydiving is not for you
