page.title=Creating an Android Project page.tags=project setup helpoutsWidget=true trainingnavtop=true next.title=Running Your App next.link=running-app.html @jd:body
An Android project contains all the files that comprise the source code for your Android app.
This lesson shows how to create a new project either using Android Studio or using the SDK tools from a command line.
Note: You should already have Android Studio or the Android SDK command-line tools installed. If not, download them before you start this lesson.
It is easier to follow these lessons if you use the same values as shown.
The Minimum Required SDK is the earliest version of Android that your app supports, indicated using the API level. To support as many devices as possible, you should set this to the lowest version available that allows your app to provide its core feature set. If any feature of your app is possible only on newer versions of Android and it's not critical to the app's core feature set, you can enable the feature only when running on the versions that support it (as discussed in Supporting Different Platform Versions).
An activity is one of the distinguishing features of the Android framework. Activities provide the user with access to your app, and there may be many activities. An application will usually have a main activity for when the user launches the application, another activity for when she selects some content to view, for example, and other activities for when she performs other tasks within the app. See Activities for more information.
Your Android project is now a basic "Hello World" app that contains some default files. Take a moment to review the most important of these:
app/src/main/res/layout/activity_my.xml
app/src/main/res/layout/content_my.xml
app/src/main/java/com.mycompany.myfirstapp/MyActivity.java
app/src/main/AndroidManifest.xml
app/build.gradle
build.gradle
file for each module of your project, as well as a build.gradle
file for the entire
project. Usually, you're only interested in the build.gradle
file for the module,
in this case the app
or application module. This is where your app's build dependencies
are set, including the defaultConfig
settings:
compiledSdkVersion
is the platform version against which you will compile
your app. By default, this is set to the latest version of Android available in your SDK.
(It should be Android 4.1 or greater; if you don't have such a version available, you must
install one using the SDK Manager.)
You can still build your app to support older versions, but setting this to the latest
version allows you to enable new features and optimize your app for a great user experience
on the latest devices.applicationId
is the fully qualified package name for your application that
you specified during the New Project workflow.minSdkVersion
is the Minimum SDK version you specified during the New Project
workflow. This is the earliest version of the Android SDK that your app supports.targetSdkVersion
indicates the highest version of Android with which you have
tested your application. As new versions of Android become available, you should
test your app on the new version and update this value to match the latest API level and
thereby take advantage of new platform features. For more information, read
Supporting Different
Platform Versions.See Building Your Project with Gradle for more information about Gradle.
Note also the /res
subdirectories that contain the
resources for your application:
drawable-<density>/
layout/
menu/
mipmap/
values/
To run the app, continue to the next lesson.