Activity fragments, for greater control of content and design flexibilityStarting with Android 3.0, developers can break the Activities of their applications into subcomponents called Fragments, then combine them in a variety of ways to create a richer, more interactive experience. For example, an application can use a set of Fragments to create a true multipane UI, with the user being able to interact with each pane independently. Fragments can be added, removed, replaced, and animated inside an Activity dynamically, and they are modular and reusable across multiple Activities. Because they are modular, Fragments also offer an efficient way for developers to write applications that can run properly on both larger screen as well as smaller screen devices.
Redesigned UI widgetsAndroid 3.0 offers an updated set of UI widgets that developers can use to quickly add new types of content to their applications. The new UI widgets are redesigned for use on larger screens such as tablets and incorporate the new holographic UI theme. Several new widget types are available, including a 3D stack, search box, a date/time picker, number picker, calendar, popup menu, and others. Most of the redesigned UI widgets can now be used as remote views in application widgets displayed on the home screen. Applications written for earlier versions can inherit the new Widget designs and themes.
Expanded Home screen widgetsHome screen widgets are popular with users because they offer fast access to application-specific data directly from the home screen. Android 3.0 lets developers take home screen widgets to the next level, offering more types of content and new modes of interaction with users. Developers can now use more standard UI widget types home screen widgets, including widgets that let users flip through collections of content as 3D stacks, grids, or lists. Users can interact with the home screen widgets in new ways, such as by using touch gestures to scroll and flip the content displayed in a widget.
Persistent Action BarThe platform provides each application with its own instance of the Action Bar at the top of the screen, which the application can use to give the user quick access to contextual options, widgets, status, navigation, and more. The application can also customize the display theme of its Action Bar instance. The Action Bar lets developers expose more features of their applications to users in a familiar location, while also unifying the experience of using an application that spans multiple Activities or states.
Richer notificationsNotifications are a key part of the Android user experience because they let applications show key updates and status information to users in real time. Android 3.0 extends this capability, letting developers include richer content and control more properties. A new builder class lets developers quickly create notifications that include large and small icons, a title, a priority flag, and any properties already available in previous versions. Notifications can offer more types of content by building on the expanded set of UI Widgets that are now available as remote Views.
Multiselect, clipboard, and drag-and-dropThe platform offers convenient new interaction modes that developers can use. For managing collections of items in lists or grids, developers can offer a new multiselect mode that lets users choose multiple items for an action. Developers can also use a new system-wide Clipboard to let users easily copy any type of data into and out of their applications. To make it easier for users to manage and organize files, developers can now add drag-and-drop interaction through a DragEvent framework.
High-performance 2D and 3D graphics
New animation frameworkThe platform includes a flexible new animation framework that lets developers easily animate the properties of UI elements such as Views, Widgets, Fragments, Drawables, or any arbitrary object. Animations can create fades or movement between states, loop an animated image or an existing animation, change colors, and much more. Adding animation to UI elements can add visual interest to an application and refine the user experience, to keep users engaged.
Hardware-accelerated 2D graphicsAndroid 3.0 offers a new hardware-accelerated OpenGL renderer that gives a performance boost to many common graphics operations for applications running in the Android framework. When the renderer is enabled, most operations in Canvas, Paint, Xfermode, ColorFilter, Shader, and Camera are accelerated. Developers can control how hardware-acceleration is applied at every level, from enabling it globally in an application to enabling it in specific Activities and Views inside the application.
Renderscript 3D graphics engineRenderscript is a runtime 3D framework that provides both an API for building 3D scenes as well as a special, platform-independent shader language for maximum performance. Using Renderscript, you can accelerate graphics operations and data processing. Renderscript is an ideal way to create high-performance 3D effects for applications, wallpapers, carousels, and more.
Support for multicore processor architecturesAndroid 3.0 is the first version of the platform designed to run on either single or multicore processor architectures. A variety of changes in the Dalvik VM, Bionic library, and elsewhere add support for symmetric multiprocessing in multicore environments. These optimizations can benefit all applications, even those that are single-threaded. For example, with two active cores, a single-threaded application might still see a performance boost if the Dalvik garbage collector runs on the second core. The system will arrange for this automatically.
Rich multimedia and connectivity
HTTP Live streamingApplications can now pass an M3U playlist URL to the media framework to begin an HTTP Live streaming session. The media framework supports most of the HTTP Live streaming specification, including adaptive bit rate.
Pluggable DRM frameworkAndroid 3.0 includes an extensible DRM framework that lets applications manage protected content according to a variety of DRM mechanisms that may be available on the device. For application developers, the framework API offers an consistent, unified API that simplifies the management of protected content, regardless of the underlying DRM engines.
Digital media file transferThe platform includes built-in support for Media/Picture Transfer Protocol (MTP/PTP) over USB, which lets users easily transfer any type of media files between devices and to a host computer. Developers can build on this support, creating applications that let users create or manage media files that they may want to transfer or share across devices.
More types of connectivityThe platform offers new connectivity that developers can build on. API support for Bluetooth A2DP and HSP profiles lets applications query Bluetooth profiles for connected devices, audio state, and more, then notify the user. For example, a music application can check connectivity and status and let the user know that music is playing through a stereo headset. Applications can also register to receive system broadcasts of pre-defined vendor-specific AT commands, such as Platronics Xevent. For example, an application could receive broadcasts that indicate a connected device's battery level and could notify the user or take other action as needed. Applications can also take advantage of the platform's new support for full keyboards connected by USB or Bluetooth.