eVaf Tutorial

11 - Buiding PswGen application

CMakeLists.txt

Copy an existing CMakeLists.txt file from the Storage module:

evaf/src/apps/PswGen/GUI $ cp ../Storage/CMakeLists.txt .

We need to modify the TARGET variable and remove QT_USE_QTSQL and QT_DONT_USE_QTGUI variables. This module needs QtGui and does not need QtSql. Als add SdiWindow to the list of eVaf libraries as the module that implements the main window.

# Name of the target
set(TARGET PswGui)

# Qt modules
include(${QT_USE_FILE})

# Required eVaf libraries
set(eVaf_LIBRARIES CommonLib PluginsLib SdiWindow)

Here is the final CMakeLists.txt file:

# src/apps/PswGen/GUI/CMakeLists.txt

# Name of the target
set(TARGET PswGui)

# Qt modules
include(${QT_USE_FILE})

# Include directories
include_directories(${eVaf_INCLUDE})

# Required eVaf libraries
set(eVaf_LIBRARIES CommonLib PluginsLib SdiWindow)

# Source files
set(SRCS
    gui.cpp
)

# Header files for the Qt meta-object compiler
set(MOC_HDRS
    gui.h
)

# Version info resource file for Windows builds
if(WIN32)
    set(SRCS ${SRCS} version.rc)
endif(WIN32)

# Run the Qt meta-object compiler
qt4_wrap_cpp(MOC_SRCS ${MOC_HDRS})

# Compile the module
add_library(${TARGET} SHARED ${SRCS} ${MOC_SRCS})

# Link the module
target_link_libraries(${TARGET} ${QT_LIBRARIES} ${eVaf_LIBRARIES})

Open the CMakeLists.txt file in the parent directory and add the command to include the GUI sub-directory:

# src/apps/PswGen/CMakeLists.txt
# ...
add_subdirectory(GUI)

Building the module

Go to the previously made build directory and build the module:

evaf $ cd build
evaf/build $ make PswGui

Check the bin directory, which should now contain two new libraries:

evaf/build $ ls bin
libCommonLib.so*  libPluginsLib.so*  libPswGen.so*  libPswGui.so*  libPswStorage.so*  libSdiWindow.so*
evaf/build $

The libSdiWindow.so library was built because it is a dependency of the GUI module.

Running the PswGen application

In the same build directory, create few more sub-directories needed by any eVaf applications:

 evaf/build $ mkdir {etc,log}

Create the PswGen.xml file in the build/etc directory. The PswGen.xml file defines the application by specifying all the modules that the application needs to load.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE eVaf>
<eVaf version="1.0">
    <plugins>
        <plugin name="SdiWindow" filename="SdiWindow" />
        <plugin name="Generator" filename="PswGen" />
        <plugin name="Storage" filename="PswStorage" />
        <plugin name="GUI" filename="PswGui" />
    </plugins>
</eVaf>

Modules are loaded and initialized in the order how they are specified in the xml file. We have to make sure that SdiWindow, Generator and Storage modules are loaded before the GUI module. Otherwise their interfaces wouldn't be available when the GUI module is initialized.

The name attribute here is optional and will be replaced with the name reported by the actual module.

The filename attribute specifies the name of the library file without prefixes and suffixes meaning that libPswGen.so shall be specified as PswGen. This makes sure that the same xml file can be also used on Windows, where the library would be called PswGen.dll.

There is no executable file yet that we can run. Build it with the following command:

evaf/build $ make eVafGUI

This command builds the GUI executable and stores it in the evaf/build/bin directory. The bin directory should look now the following:

evaf/build $ ls bin
eVafGUI*  libCommonLib.so*  libPluginsLib.so*  libPswGen.so*  libPswGui.so*  libPswStorage.so*  libSdiWindow.so*
evaf/build $

Now we can run the PswGen application. Change --dataroot=${HOME}/evaf/build to your actual build directory name:

evaf/build $ bin/eVafGUI --application=PswGen --dataroot=${HOME}/evaf/build --verbose=INFO

The --application=PswGen command line option specifies the name of the application and also means that the xml file should be called PswGen.xml. Different applications can be run in the same build directories by changing the name of the application. The default application is called eVaf and if no name is given, then the xml file should be called eVaf.xml.

The --dataroot=${HOME}/evaf/build command line option specifies the location of data files for the application. The application assumes that etc and spool directories are sub-directories in the data root directory. The default data root directory is ${HOME}/.local/share/data on Linux.

Finally, the --verbose=INFO command line option makes the application to be verbose and output all the info messages to the console.

Releasing the PswGen application

Now the application is written and tested. We are ready to make a release build and ship it.

Clean the build directory:

evaf/build $ make clean && rm CMakeCache.txt

Prepare for a release build and build the application:

evaf/build $ cmake -DCMAKE_BUILD_TYPE=Release ..
evaf/build $ make eVafGUI SdiWindow PswGen PswStorage PswGui

Packaging and shipping the application is out of the scope of this tutorial and involves more than just copying files that we built. As a minimum, we have to make sure that the target system has Qt libraries installed. In this tutorial, we simply copy the released application into the {$HOME}/bin/evaf directory. Qt libraries are already installed and we do not need to worry about them.

Create the ${HOME}/bin/evaf directory:

evaf/build $ mkdir -p ${HOME}/bin/evaf

Copy the content of bin and etc directories

evaf/build $ cp -R bin etc ${HOME}/bin/evaf/

Create the bash script PswGen in the ${HOME}/bin directory:

#!/bin/bash
EVAF_DIR=${HOME}/bin/evaf
${EVAF_DIR}/bin/eVafGUI --rootdir=${EVAF_DIR} --dataroot=${EVAF_DIR} --application=PswGen

Don't forget to make it runnable:

 bin $ chmod a+x PswGen

Now we can run the application by simply running the bash script PswGen in the ${HOME}/bin directory.