Category Archives: Eclipse

Install Android SDK and Tools with Eclipse in Ubuntu, Mac OS X and Windows

Here I’ll explain the process to install Android SDK and Tools. There are 4 things you have to install in order to develop Android applications:

  • Android SDK
  • Eclipse
  • Android Development Tools plugins for Eclipse (ADT)
  • Android Virtual Device (ADV)

Android SDK

You can download the latest version of the Android SDK for your OS at the official Android SDK web. Latest versions at the time of this writing are those:

Ubuntu android-sdk_r24.4.1-linux.tgz
Mac OS X android-sdk_r24.4.1-macosx.zip
Windows android-sdk_r24.4.1-windows.zip

Once downloaded uncompress it anywhere you like in your hard drive. It can be for example in your users home folder (/home/username/android-sdk-linux for Ubuntu, /Users/username/Applications/android-sdk-macosx for Mac OS X, C:\Documents and Settings\username\android-sdk-windows for Windows XP, C:\Users\username\android-sdk-windows for Windows Vista/7/8/10) or beside other applications (/usr/lib/android-sdk-linux for Ubuntu, /Applications/android-sdk-macosx for Mac OS X, C:\Program Files\android-sdk-windows for Windows).

Be sure you have configured the JAVA_HOME, ANDROID_HOME and PATH environment variables:

In Linux edit the ~/.bashrc file:

export JAVA_HOME=$(readlink -f /usr/bin/java | sed "s:/bin/javac::")
export ANDROID_HOME=~/android-sdk-linux
export PATH=$PATH:~/android-sdk-linux/tools

For Mac OS X you should edit the ~/.bash_profile file:

export JAVA_HOME=$(/usr/libexec/java_home)
export ANDROID_HOME=~/Applications/android-sdk-macosx
export PATH=$PATH:~/Applications/android-sdk-macosx/tools

Eclipse

For Eclipse installation just go to https://eclipse.org/downloads/, download it and install it.

Android Development Tools

Open Eclipse and go to “Help→Install New Software”, click “Add…” and enter “ADT Plugin” for “Name” and “https://dl-ssl.google.com/android/eclipse/” for “Location”.

eclipse-add-new-software

eclipse-add-new-software-adt-plugin

Select that repository in “Work with:”, choose all the packages and proceed the installation. Click OK if you see a message saying that unsigned content is being installed . Once installed you have to restart Eclipse.

After the restart, Eclipse will ask you to configure the Android SDK location. Click “Open Preferences”, select “Use existing SDKs” and fill “Existing Location” with the path you used to decompress Android SDK. If you don’t configure it now you can configure it anytime in the Eclipse preferences under the Android options.

eclipse-preferences-android

After configuring the Android SDK location path you will be asked to install SDK Platform Tools. Click “Open SDK Manager” (or select “Window->Android SDK Manager”), select all the packages inside “Tools” and the version of Android of your choice (I used 4.2) and click “Install X packages…”. Don’t worry if you see “Stopping ADB server failed (code -1).” in the log messages, it’s OK.

Android Virtual Device

Now that everything is installed you have to create an Android Virtual Device (AVD) so you can use the emulator. Open the Java perspective (Window->Open Perspective->Java or click the icon with the yellow plus sign at the top right of the IDE and select Java). You will see 2 new icons with the Android symbol in the tools bar. Click the one on the right that looks like a phone (the other one opens the Android SDK Manager), click “New…” and give your Android Virtual Device a name, a device type, a target, etc. If you can’t select a target just restart Eclipse so it can load the newly installed SDK Platform Tools.

In Ubuntu for 64 bit systems you can get this error when creating an AVD:

Error: Failed to create the SD card.
Error: Failed to create sdcard in the AVD folder.

To solve it install the ia32-libs libraries (http://stackoverflow.com/questions/3878445/ubuntu-error-failed-to-create-the-sd-card). Beware that they are about 260MB:

sudo apt-get install ia32-libs

Your first Android Application

Now you are ready to create your first Android application. Create a new “Android Application Project” with all the default options, just fill a “Application Name” like “Hello World”. The default option uses a “BlankActivity” with a template that needs the the Adroid Support library. It will ask you to install it and is as simple as clicking the “Install/Upgrade” button showed in that dialog window.

And there you have a fresh new “Hello Word” Android application. If you make the mistake of clicking the “Run” button you will get an error like this:

Error in an XML file: aborting build

That’s because by default the opened file after creating this “Hello World” project is “activity_main.xml”. You can also notice that a new file called “activity_main.out.xml” has been created, and it even is marked with errors. Delete that newly created file and open the “MainActivity.java” file under “src” folder. Now you can click the “Run” button. Select “Android Application” in the “Run As” dialog window.

I had a problem in Mac OS X Lion after running the emulator several times. When I tried to run the application the emulator crashed every time. Searching on the Internet I found this page where it explains that if you run the emulator in a secondary monitor and close it while in that monitor, a value of the X position of the window is stored and next time that value is bigger that the first monitors resolution and chashes. Deleting the emulator-user.ini file from the /Users/username/.android/avd/device_name folder (executing open /Users/username/.android/avd/device_name from a terminal window) and running the emulator again solved the problem.

As a hint I always deselect “Project->Build Automatically” option because I prefer to build the code manually pressing Control+B or Command+B.

Sources: http://developer.android.com/sdk/installing/installing-adt.html
http://developer.android.com/sdk/installing/adding-packages.html

Use OpenCV in Eclipse CDT

Install OpenCV (see previous posts for Ubuntu 10.10, Ubuntu 11.10, Ubuntu 12.04 and OpenCV 2.4 in Ubuntu 12.04).

Install Eclipse CDT:

sudo apt-get install eclipse-cdt

Open Eclipse CDT and select a workspace (it’s just a path to store projects together). Create a new “C++ Project”, give it a name and select “Empty Project” on “Project type” and “Linux GCC” on “Toolchains”.

Right click on the project folder and select “Properties”. Go to “C/C++ Build->Settings”. Then, inside “Tool Settings” tab, go to “GCC C++ Compiler->Includes” and fill “Include paths (-l)” with the path of your OpenCV include installation. If you installed OpenCV from the source code it will possibly be “/usr/local/include/opencv2” (or the path you entered in CMAKE_INSTALL_PREFIX when configuring with CMake), but if you installed from the repositories it should be “/usr/include/opencv2“.

Now go to “GCC C++ Linker->Libraries” and fill “Libraries (-l)” with (at least) those OpenCV libraries:

opencv_core
opencv_highgui

And “Library search paths (-L)” with the path location of your OpenCV installation libraries. As before, if you installed from the source it should be “/usr/local/lib” (same here with CMAKE_INSTALL_PREFIX) and if you installed with repositories “/usr/lib“.

Now it’s time to code. Go to “File->New->Source file” and create a new file called “main.cpp“. Fill it with:

#include "opencv.hpp"

int main(int argc, char* argv[])  {

	IplImage* img = cvCreateImage( cvSize( 640, 480 ), IPL_DEPTH_8U, 3 );

	cvCircle( img, cvPoint( 320, 240 ), 100, cvScalar( 255, 0, 0 ), 5 );

	cvNamedWindow( "OpenCV Window", CV_WINDOW_NORMAL );
	cvShowImage( "OpenCV Window", img );

	cvWaitKey(0);

	cvDestroyWindow( "OpenCV Window" );
	cvReleaseImage( &img );

	return 0;
}

This code will just show a black window with a blue circle in it and end when you press any key. Not very fancy but we just want to check if all runs OK.

Eclipse CDT comes with an option to build automatically, but I always disable it deselecting “Project->Build Automatically”. Build all by pressing Control+B or going to “Project->Build All”. Before debugging/running our application we need to configure the debugging/running environment. Go to “Run->Debug Configurations…” and do a double click on “C/C++ Application”. It will create a new debug configuration, but “C/C++ Application” parameter may not be automatically configured (this happend to me), so use “Browse…” button to select a “Project”, select your current project, and now (if your application binary program does exist) all should be OK to push “Debug” button.

You should now be able to run and debug your OpenCV application. Using any other library with Eclipse CDT is pretty much the same.