Qt Creator and Scratchbox

 

Qt Creator is perfect tool for Qt
application development, it is first IDE that i have fallen love and
even as old hacker I have been ready to trade my old emacs to it.
These is one missing feature that so many has asked from me,
scratchbox support. It may be one of most requested feature among
advanced Maemo/MeeGo developers. Currently QtCreator from Nokia SDK does
not support Scratchbox toolchain. Most of current experienced Maemo
developers prefer scratchbox because it allows also development of
complex applications that are using in Linux build tools and it
allows running application under simulated ARM or x86 environment with full
Maemo library and style support. From picture above you can see
exatly same application run under simulator and under scratchbox.

Getting Qt Creator supporting
scratchbox is not so difficult, it just needs some small tweaks.

Make Paths symmetric

First make your paths symmetric under
scratchbox and host Linux environment. That means that if your
application path is /a/b/c/d under host, it is found under same path
under scratchbox. I do this normally doing symlink my directory
scratchbox under scratchbox home directory under
/home/kate/scratchbox, so path to my application should be
/home/kate/scratchbox/myapp under both scratchbox and host Linux.

You can do it with following command on
Linux host.

mkdir
/scratchbox/users/$USER/home/$USER/scratchbox
ln
-s /scratchbox/users/$USER/home/$USER/scratchbox scratchbox

VMWare issues

If you are running your scratchbox
under VMWare virtual machine, you may want to have your working
directory under host filesystem so that files are available also from
your host side. This should least work under Linux and Mac hosts that
both share common unix filesystem schematics. As example in Mac, I
have under my Mac home directory subdirectory scratchbox that is
mounted under my virtual Linux host as /mnt/hgfs . Under my VMWare Linux, i
have from my Linux home directory symbolic link scratchbox ->
/mnt/hgfs/scratchbox .

To have write access you need to have
also matching UID’s in both sides. Under Mac OSX default user is 501
but under Ubuntu it is 1001. To get matching user ID, you should make
your user under Ubuntu have this same UID 501. By default system is
not allowing it but you can change FIRST_UID to 500 and
LAST_SYSTEM_UID as 499 in /etc/adduser.conf

To get this same VMWare host directory
visible under scratchbox, you also need one extra step. Scratchbox is
chrooted environment and it sees only files inside of chroot jail and
this mount should be bind-mount to be visible by command

mount
-o bind /mnt/hgfs/scratchbox
/scratchbox/users/kate/home/kate/scratchbox

Compiler Scripts

To compile, you need to create under
your Linux host two shell scripts /usr/bin/sbox-qmake and
/usr/bin/sbox-make as follows

/usr/bin/sbox-make

#!/bin/sh
/usr/bin/scratchbox
-d $PWD make $@

/usr/bin/sbox-qmake

#!/bin/sh
/usr/bin/scratchbox
-d $PWD qmake $@

You also need make them executable by

chmod
755 /usr/bin/sbox-qmake /usr/bin/sbox-make

Easy way to do it is use following cut
and paste friendly way

 

 echo ‘#!/bin/sh’ >/usr/bin/sbox-qmake;echo ‘/usr/bin/scratchbox -d $PWD
qmake $@’ >>/usr/bin/sbox-qmake;chmod 755 /usr/bin/sbox-qmake
echo
‘#!/bin/sh’ >/usr/bin/sbox-make;echo ‘/usr/bin/scratchbox -d $PWD
make $@’ >>/usr/bin/sbox-make;chmod 755 /usr/bin/sbox-make

Create Scratchbox Qt version under Qt Creator

Under Qt Creator, you should go under
projects, select desktop target because maemo target does not allow
you to chose custom Qt version. Select desktop targer, section
General, give configuration name, as example Sbox-qt, Choose “Manage”
from Qt Version line and open Qt version management dialog. There,
press “+” button and enter as “Version Name” sbox-qt and as
“qmake Location” the location of your sbox-qmake script location
/usr/bin/sbox-qmake . If everything went right, you should see text
“Found Qt version 4.7.0 using mkspec linux-g++ (Desktop)”

 

 

When
you return to “Build settings” page, your “Build steps” qmake
should be already correct sbox-qmake. Make is still just “make”,
you should select “details” from Make and set “Override make”
as /usr/bin/sbox-make .

 

 

 

That’s all, if everything went correctly, you could go back to your project
and select form menu “Build” and “Build project: your project
name”. It should build it under scratchbox and parsing error
messages should also work.

Running under scratchbox

For running your application from scratchbox, you need /usr/bin/sbox-run
script, there is little trick here. Qt Creator expands symbolic
links, so /home/kate/scratchbox becomes
/scratchbox/users/kate/home/kate, scratchbox run-standalone.sh script
does not like that kind of path, so prefix need to be removed

/usr/bin/sbox-run
( for fremantle )

#!/bin/sh
/usr/bin/scratchbox
-d `echo $PWD| sed -e "s_/scratchbox/users/[A-Za-z0-9]*/_/_"`
run-standalone.sh $@

You also need append export DISPLAY=:2
to end of your scratchbox .bashrc, following cut and paste friendly way

echo
export DISPLAY=:2 >>/scratchbox/users/$USER/home/$USER/.bashrc

When
all this is done, start your Xephyr from Linux host by

Xephyr
:1 -host-cursor -screen 800x480x16 -dpi 96 -ac &

and under scratchbox

af-sb-init.sh
start

Under your Qt Creator prohject, go to "Run" settings,  Add "Custom executable" and there sbox-run and name of your executable asargument.

Now you can run your Qt application under scratchbox just pressing green
run symbol from your Qt Creator.

Using Host Qt Creator under Mac

Because Mac OSX is Unix based, it is with certain limitations possible to
compile under VMWare scratchbox with little tricks. These
instructions are not complete and you may need your own expementing
to get them work. You need to do same thing, make paths symmetric. Under Mac OSX users home
is /Users/<username>, and you need maka same symlink under
scratchbox.

You can run scratchbox commands under VMWare using ssh, so make
following versions of sbox-qmake and sbox-make scripts, replace
kate/kathy as your username and virtual machine IP with your one.

/usr/bin/sbox-qmake

#!/bin/sh
ssh
kathy@172.16.109.212 "scratchbox -d $PWD qmake $@"

/usr/bin/sbox-make

#!/bin/sh
ssh
kathy@172.16.109.212 "scratchbox -d $PWD make $@"

You
also need to set up your mac ssh public key under VMWare Linux
.ssh/authorized_keys .

VMWare has nasty feature to change your virtual machine address in fly and
these scripts have address as hard coded, more advanced scripts could
take this address automatically or then we need find option from
VMWare not to change address.

Before setting new Qt target you should create on mac host empty directory
/usr/include/qt4 and copy /usr/share/qt4/mkspecs from your scratchbox
to mac host filesystem. May be advanced scripts could tweak paths
returned by sbox-qmake -query to point under virtual machine but
tahat’s future project. I have also tried “headless” scratchbox
support using Mac OSX Xephyr as display but leas in my tests Xephyr
has crashed. It may need building from sources up to date Xephyr but
that’s also possible future project. Advantage in Headless version is
that VMWare appliance is completely hidden behind QtCreator.

Using Qt Creator host under Windows

No hope