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Compile and Run SDK Example Application

Developing for Qtopia
The Qtopia SDK
- The Example Application
- Building Your Own Applications

Developing for Qtopia

Qtopia is a windowing system for handheld devices. It offers developers the powerful Qt API, and provides users with fast and intuitive interaction.

Since Qtopia offers the complete Qt API, you can do much of your development on any of the other platforms for which Qt is available: Windows, Unix/X11, or Mac OS X. However, for optimal tailoring of your application to the smaller screen and other limitations of a small device, we recommend that you use the Qtopia SDK.

The Qtopia SDK

The Qtopia SDK allows you to develop Qtopia applications under the Linux desktop environment using the Qt Virtual Framebuffer, which completely emulates the handheld Qtopia environment. It also includes cross-compiler software so that you can compile your application to run on the target device. If you do not already have the Qtopia SDK (this document is normally part of the SDK), contact info@trolltech.com, or see the Trolltech web site.

To build applications for the SHARP SL5000 or similar StrongARM-based devices, you will also need a StrongARM cross compiler.

The Example Application

The SDK includes an example application. We recommend that you compile and run this example to learn how things work, before tackling your own projects.

Here are the steps necessary to compile and run the example program on the Linux desktop:

Check that the environment is correct: For the Qtopia SDK use

   export QPEDIR=/opt/Qtopia
   export QTDIR=$QPEDIR
   export PATH=$QTDIR/bin:$PATH
   export QMAKESPEC=qws/linux-generic-g++
   export LD_LIBRARY_PATH=$QTDIR/lib:$LD_LIBRARY_PATH

otherwise the following example may be used:

   cd ~/buildQtopia
   export QTOPIA_PREFIX=$PWD
   export QPEDIR=`echo $QTOPIA_PREFIX/qtopia-*2.*.0`
   if ! test -d "$QPEDIR";then echo 'A Qtopia directory was not found!';fi
   export QTDIR="$QTOPIA_PREFIX/qt-2.3.2"
   export QTEDIR=`echo $QTOPIA_PREFIX/qt-2.3.*`
   if ! test -d "$QTEDIR";then echo 'A Qt/Embedded directory was not found!';fi
   export PATH=$QPEDIR/bin/:$QTEDIR/bin:$QTDIR/bin:$PATH
   export QMAKESPEC=qws/linux-generic-g++
   export LD_LIBRARY_PATH=$QPEDIR/lib/$QTEDIR/lib:$QTDIR/lib:$LD_LIBRARY_PATH
   export QTDIR=$QTEDIR

where ~/buildQtopia is replaced by the path to the Qtopia prefix directory

Make a copy of the example:

   cd somewhere
   cp -r $QPEDIR/examples/application .
   cd application

Generate a Makefile:
```
   qmake -o Makefile example.pro
```
Build the example:
```
   make
```

Install the example:

   su # root privileges required to install
   cp example.desktop $QPEDIR/apps/Applications/
   cp Example.png $QPEDIR/pics/
   cp example $QPEDIR/bin/
   cp example.html $QPEDIR/help/html/
   exit # no need to be root anymore

To run the example, first run the Qt Virtual Framebuffer:
```
   qvfb &
```
Then run the Qtopia environment:
```
   qpe
```
Your application should now be available in the Applications tab which is visible inside the Qt Virtual Framebuffer window.
If you want to distribute your applications to others, build an RPM package. For example:
```
   mkipks -rpm -arch i386 example.control
```

To make your own application, use the example program as a model. Make sure that when you add files to your project, you also add them to your project file (i.e. to example.pro) and rerun the qmake command to update the Makefile whenever you update the .pro file.

To build you application for the SHARP SL5000 rather than just running on the desktop, the process is similar. The example below assumes you have installed the cross compiler in /usr/local/arm.

Check the environment is correctly set for the SHARP SL5000: For the Qtopia SDK use

   export QPEDIR=/opt/Qtopia/sharp
   export QTDIR=$QPEDIR
   export QMAKESPEC=qws/linux-sharp-g++
   export PATH=$QTDIR/bin:/usr/local/arm/bin:$PATH

otherwise the following example may be used:

   cd ~/buildQtopiaSharp
   export QTOPIA_PREFIX=$PWD
   export QPEDIR=`echo $QTOPIA_PREFIX/arm/qtopia-*2.*.0`
   if ! test -d "$QPEDIR";then echo 'A Qtopia directory was not found!';fi
   export QTDIR="$QTOPIA_PREFIX/qt-2.3.2"
   export QTEDIR=`echo $QTOPIA_PREFIX/arm/qt-2.3.*`
   if ! test -d "$QTEDIR";then echo 'A Qt/Embedded directory was not found!';fi
   export PATH=$QPEDIR/bin/:$QTEDIR/bin:$QTDIR/bin:/usr/local/arm:$PATH
   export QMAKESPEC=qws/linux-sharp-g++
   export QTDIR=$QTEDIR

where ~/buildQtopiaSharp is replaced by the path to the Qtopia prefix directory that suits your target device.

Rebuild the makefile ($QMAKESPEC has changed) above:

   make clean
   qmake -o Makefile example.pro

Build it:
```
   make
```

Install it (note that this is now going into the /opt/Qtopia/sharp/ directory):

   su # root privileges required to install
   cp example.desktop $QPEDIR/apps/Applications
   cp Example.png $QPEDIR/pics
   cp example $QPEDIR/bin
   cp example.html $QPEDIR/help/html/
   exit # no need to be root anymore

To install it on a device, build an ipk package file:

   su -m # root privileges required to strip the executable
   mkipks example.control
   exit # no need to be root anymore

The resulting example-1.0.0.ipk can be installed on the SL5000 using Qtopia Desktop.

Building Your Own Applications

Once you have built the example, you can proceed with writing your own applicatons. If you are not familiar with Qt, you should consult the Qt documentation by pointing your web browser at /opt/Qtopia/doc/index.html when you have installed the SDK, or use the online Trolltech Documentation Site. The Qt Whitepaper provides a good overview of, and introduction to, the Qt API.

When you add more files to your application, just edit the project file (e.g. example.pro) and rerun qmake.

The .ui files are Qt Designer user interface files. You can create and edit these using Qt Designer:

   designer example.ui

Qt Designer's online documentation (accessible from the links mentioned above) includes a complete tutorial.

Trademarks

Qtopia version 2.0.1