jueves, 4 de octubre de 2012

What do I need to start programming Android?


Creating an Android Development Environment
The Android Software Development Kit supports Windows (XP and Vista), Linux (Ubuntu Dapper Drake), and Mac OS X (10.4.8 or later) as host development environments. Installation of the SDK is substantially the same for any of the operating systems, and most of this description applies equally to all of them. Where the procedure differs, we will clearly tell you what to do for each environment.

1. Install Eclipse: The Android SDK requires Eclipse version 3.2 or 3.3 (also known as Europa) or later. If you do not have that version of Eclipse installed yet, you will need to go to http://www.eclipse.org/downloads to get it, and you might as well get version 3.3 since that package includes the required plugins mentioned in the next step. You want the version of the Eclipse IDE labeled "Eclipse IDE for Java Developers," and obviously you want the version for your operating system. Eclipse will ask you to select a mirror site, and will then start the download.
Windows (XP or Vista)
The Eclipse download comes as a big ZIP file that you install by extracting the files to your favorite directory. For this book, we'll assume that you extracted to C:/eclipse. Eclipse is now installed, but it will not show up in your Start menu of applications. You may want to create a Windows shortcut for C:/eclipse/eclipse.exe and place it on your desktop, in your Start menu, or someplace else where you can easily find it.

Linux and Mac OS X
The Eclipse download comes as a big tarball (.gz file) that you install by extracting the files to your favorite directory. For this book, we'll assume that you extracted to /usr/lib/eclipse.
2. Check for Required Plugins: You can skip this step if you just downloaded a current version of Eclipse as we recommended. If you are using a pre-installed version of Eclipse that was already on your PC, you need to make sure you have the Java Development Tool (JDT) and Web Standard Tools (WST) plug-ins installed. You can easily check to see whether they are installed by starting Eclipse and selecting menu options "WIndows -> Preferences..." The list of preferences should include one for "Java" and one for "Web and XML." If they aren't on the list, the easiest thing to do is reinstall Eclipse, as described in the previous step. Installing "Eclipse IDE for Java Developers" will automatically get the needed plugins.

3. Install JDK: The Android SDK requires JDK version 5 or version 6. If you already have one of those installed, skip to the next step. In particular, Mac OS X comes with the JDK version 5 already installed, and many Linux distributions include a JDK. If the JDK is not installed, go to http://java.sun.com/javase/downloads and you'll see a list of Java products to download. The one you want is JDK 6 Update n for your operating system, where n is 6 at the time this is written.

Windows (XP and Vista)
Select the distribution for "Windows Offline Installation, Multi-language."
Read, review, and accept Sun's license for the JDK. (The license has become very permissive, but if you have a problem with it, alternative free JDKs exist.)
Once the download is complete, a dialog box will ask you whether you want to run the downloaded executable. When you select "Run," the Windows Installer will start up and lead you through a dialog to install the JDK on your PC.

Linux
Select the distribution for "Linux self-extracting file."
Read, review, and accept Sun's license for the JDK. (The license has become very permissive, but if you have a problem with it, alternative free JDKs exist.)
You will need to download the self-extracting binary to the place you want to install the JDK on your filesystem. If that place is a system wide directory (such as /usr/local), you will need root access. After the file is downloaded, make it executable (chmod +x jdk-6version-linux-i586.bin) , and execute it. It will self-extract to create a tree of directories.

Mac OS X
Mac OS X comes with JDK Version 5 already loaded.
4. Install Android SDK: This is where you'd start if you already have the right versions of Eclipse and the JDK loaded. The Android SDK is distributed through Google's code site, http://code.google.com/android/download.html. You will need to read, review and accept the terms of the license to proceed. When you get to the list of downloads, you will see a table of distributions. Select the one for your operating system (XP and Vista use the same distribution). The package (file) names include the release number. For example, as this is written, the latest version of the SDK is 1.0_r1, so the file you would download for Windows is named android-sdk-windows-1.0_r1.zip.
The file you download is another archive file, as with Eclipse: a ZIP file on Windows, a tar-zipped file for Linux and MacOS X. Do the same thing as for Eclipse: extract the archive file to a directory where you want to install Android, and make a note of the directory name (you'll need it in Step 7). The extraction will create a directory tree containing a bunch of sub-directories, including one called tools.
5. Update Environment Variables: To make it easier to launch the Android tools, add the tools directory to your path.
Under Windows XP, click on Start, then right-click on My Computer. In the pop-up menu, click on Properties. In the resulting System Properties dialog box, select the Advanced tab. Near the bottom of the Advanced tab is a button, "Environment Variables," that takes you to an Environment Variables dialog. User environment variables are listed in the top half of the box, System environment variables in the bottom half. Scroll down the list of System environment variables until you find "Path," select it, and click the "Edit" button. Now you will be in an Edit System Variable dialog that allows you to change the environment variable "Path." Add the full path of the tools directory to the end of the existing Path variable and click "OK." You should now see the new version of the variable in the displayed list. Click "OK" and then "OK" again to exit the dialog boxes.
On Windows Vista, click on the Microsoft "flag" in the lower left of the desktop, then right-click on Computer. At the top of the resulting display, just below the menu bar, click on "System Properties." In the column on the left of the resulting box, click on "Advanced system settings." Vista will warn you with a dialog box that says "Windows needs your permission to continue";- click "Continue." Near the bottom of the "System Properties" is a button labeled "Environment Variables" that takes you to an Environment Variables dialog. User environment variables are listed in the top half of the box, System environment variables in the bottom half. Scroll down the list of System environment variables until you find "Path," select it, and click the "Edit" button. Now you will be in an Edit System Variable dialog that allows you to change the environment variable "Path". Add the full path of the tools directory to the end of the existing Path variable, and click "OK." You should now see the new version of the variable in the displayed list. Click "OK" and then "OK" again to exit the dialog boxes.
On Linux, the PATH environment variable can be defined in your ~/.bashrc ~/.bash_profile file. If you have either of those files, use a text editor such as gedit, vi, or Emacs to open the file and look for a line that exports the PATH variable. If you find such a line, edit it to add the full path of the tools directory to the path. If there is no such line, you can add a line like this:
export PATH=${PATH}:your_sdk_dir/tools
where you put the full path in place of
your_sdk_dir.
On MacOS X, look for a file named .bash_profile in your home directory (note the initial dot in the filename). If there is one, use an editor to open the file and look for a line that exports the PATH variable. If you find such a line, edit it to add the full path of the tools directory to the path. If there is no such line, you can add a line like this:
export PATH=${PATH}:your_sdk_dir/tools
where you put the full path in place of
your_sdk_dir
6. Install the Android Plugin (ADT): Throughout this book, we will make use of the Android Development Tool plugin that Google supplies for use in building Android applications. The plugin is installed in much the same way as any other Eclipse plugin:
Start Eclipse, if it's not already running.
From the menu bar, select "Help -> Software Updates -> Find and Install..."
  • In the Install/Update dialog, select "Search for new features to install" and click on "Next."
  • In the Install dialog, click on "New Remote Site." A "New Update Site" dialog pops up. Enter a name for the plugin ("Android Plugin" will do), and the URL for updates: https://dl-ssl.google.com/android/eclipse. Click "OK."
  • The new site should now appear in the list of sites on the Install dialog. Click "Finish."
  • In the Search Results dialog, select the checkbox for "Android Plugin -> Developer Tools" and click "Next."
  • The license agreement for the plugin appears. Read it, and if you agree, select "Accept terms of the license agreement" and click "Next." Click "Finish."
  • You will get a warning that the plugin is not signed. Choose to install it anyway by clicking "Install All."
  • Restart Eclipse.
  • After Eclipse restarts, you need to tell it where the SDK is located. From the menu bar, select "Window -> Preferences." In the Preferences dialog, select "Android" in the left hand column.
  • Use the "Browse" button to navigate to the place you installed the Android SDK, and click on "Apply," then on "OK."
Congratulations--you have installed a complete Android development environment without spending a penny. As you'll see in this and subsequent chapters, the environment includes a very sophisticated set of tools to make Android programming easier, including:
An Integrated Development Environment based on Eclipse, arguably the premier IDE for Java development. Eclipse itself brings many valuable development features. Google and OHA have taken advantage of Eclipse's extensibility to provide features customized for Android, including debugging capabilities that are tuned to the needs of mobile application developers like you.
A Java development environment and Dalvik virtual machine that build on Sun's JDK foundation to provide a very sophisticated programming environment for your applications.
A complete mobile phone emulator that allows you to test your applications without having to download them to a target mobile phone. The emulator includes features for testing your application under different mobile phone communication conditions (fading, dropped connections, etc.).

source: HowToForge

No hay comentarios:

Publicar un comentario