[haiku] Deskbar won't "Close All"; who to blame :)
- From: Caitlin Shaw <rogueeve@xxxxxxxxxxxxx>
- To: haiku@xxxxxxxxxxxxx
- Date: Sat, 24 Oct 2009 19:36:40 -0700
I've been investigating an issue I discovered yesterday; which is that
on several of my programs the Deskbar "Close All" option (under the
window list menu) results in... nothing happening.
Tracking it down, I discovered at the bottom of ShowHideMenuItem.cpp in
the Deskbar app the code for "Close All". The Deskbar constructs a
BMessenger off of the team ID of the application, and then attempts to
send the app a B_QUIT_REQUESTED message through that messenger. The
problem is that the BMessenger instantiation is failing with B_BAD_TYPE.
And the reason for that, is that that is what a BMesssenger does if the
application has B_ARGV_ONLY set in the application flags resource. The
applications in question don't make use of any of the special
application flags, so I didn't provide a flags resource. And it seems
that if you don't provide the flags, the system returns some default
ones when asked for them, and those defaults include B_ARGV_ONLY.
So, know that I now how to fix it, I'm wondering whether this is a
series of sensible behaviors that together culminate in an unfortunate
error, or is it by design and I was very very bad not to include an
application flags resource in my program. I know you are supposed to
specify a signature, but I had always assumed that the other resources
such as icons and flags were optional, especially since the FileTypes
applet includes a checkbox for turning the use of app flags on and off.
It seems that perhaps the system could include the B_ARGV_ONLY flag
based on the app signature being missing instead of the flags being
missing; if the signature is missing it is obviously a unix or terminal
app like "ls", etc so the flag is appropriate. Alternatively, the
Deskbar could check for that condition and in that case try to quit the
app some other way, such as sending messages to all of it's open
windows, or sending a posix SIGTERM.
Of course, if neglecting to provide a flags resource is Absolutely
Wrong, then it's all my "fault" and that fact just needs to be
documented somewhere in the Hello World type guides, which I sure it
will be once the OS gets a little more popular, or may even already be.
FYI, here's the test program. The window it produces fails to close via
"Close All". Clicking the big "Quit" button is supposed to quit the app
by constructing a BMessenger off of the team id in the same way as the
Deskbar does, but it doesn't work because the BMessenger fails to
instantiate. If you open the binary in FileTypes and manually check the
"Application Flags" box, then it starts working.
#include <Application.h>
#include <Window.h>
#include <Button.h>
#include <Roster.h>
#include <stdio.h>
#include <string.h>
#define SIGNATURE "application/xvnd-Kt.NoClose"
#define M_QUIT_PRESSED 'MQPR'
class QuitButton : public BButton
{
public:
QuitButton(BRect frame, const char *label)
: BButton(frame, NULL, label, new BMessage(M_QUIT_PRESSED),
B_FOLLOW_ALL)
{ }
};
class MyWindow : public BWindow
{
public:
MyWindow(BRect frame)
: BWindow(frame, "Can't Close", B_TITLED_WINDOW, 0)
{
BRect rc(Bounds());
rc.InsetBy(20, 20);
AddChild(new QuitButton(rc, "QUIT APP"));
Show();
}
void MessageReceived(BMessage *msg)
{
char what_code[5];
what_code[0] = (msg->what >> 24) & 255;
what_code[1] = (msg->what >> 16) & 255;
what_code[2] = (msg->what >> 8) & 255;
what_code[3] = msg->what & 255;
what_code[4] = 0;
printf("window: got message '%s'\n", what_code);
fflush(stdout);
if (msg->what == M_QUIT_PRESSED)
{
team_id team = be_app->Team();
status_t error = -1;
uint32 command = B_QUIT_REQUESTED;
printf("\n------------\n");
app_info info;
info.flags = 0;
if (be_roster->GetRunningAppInfo(team, &info) == B_OK)
{
printf("app flags = %08x\n", info.flags);
if (info.flags & B_ARGV_ONLY)
printf("Warning: info.flags has B_ARGV_ONLY set\n");
}
printf("Creating messenger with NULL sig and
team_id=%d...\n", team);
BMessenger messenger((char*)NULL, team, &error);
switch(error)
{
case B_OK: printf("OK!\n"); break;
case B_BAD_VALUE: printf("B_BAD_VALUE!\n"); break;
case B_BAD_TYPE: printf("B_BAD_TYPE!\n"); break;
case B_BAD_TEAM_ID: printf("B_BAD_TEAM_ID!\n"); break;
case B_MISMATCHED_VALUES:
printf("B_MISMATCHED_VALUES!\n"); break;
case B_BAD_HANDLER: printf("B_BAD_HANDLER!\n"); break;
}
printf("error = %08x : %s\n", error, strerror(error));
printf("attempting to send B_QUIT_REQUESTED...\n");
fflush(stdout);
messenger.SendMessage(command);
}
BWindow::MessageReceived(msg);
}
bool QuitRequested()
{
printf("Window: Quit Requested!\n");
fflush(stdout);
be_app->PostMessage(B_QUIT_REQUESTED);
return BWindow::QuitRequested();
}
};
class MyApp : public BApplication
{
public:
MyApp(const char *sig)
: BApplication(sig)
{
printf("MyApp() constructor\n");
fflush(stdout);
}
void ReadyToRun()
{
printf("ReadyToRun!\n");
fflush(stdout);
MyWindow *win = new MyWindow(BRect(200, 200, 500, 500));
}
bool QuitRequested()
{
printf("App: Quit Requested!\n");
fflush(stdout);
return BApplication::QuitRequested();
}
};
int main(int argc, char *argv[])
{
new MyApp(SIGNATURE);
be_app->Run();
delete be_app;
return 0;
}
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