74 lines
4.3 KiB
Plaintext
74 lines
4.3 KiB
Plaintext
page.title=Animation and Graphics Overview
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@jd:body
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<p>Android provides a variety of powerful APIs for applying animation to UI elements and drawing custom
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2D and 3D graphics. The sections below provide an overview of the APIs and system capabilities available
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and help you decide with approach is best for your needs.</p>
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<h3 id="animation">Animation</h3>
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<p>The Android framework provides two animation systems: property animation
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(introduced in Android 3.0) and view animation. Both animation systems are viable options,
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but the property animation system, in general, is the preferred method to use, because it
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is more flexible and offers more features. In addition to these two systems, you can utilize Drawable
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animation, which allows you to load drawable resources and display them one frame after
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another.</p>
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<dl>
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<dt><strong><a href="{@docRoot}guide/topics/graphics/prop-animation.html">Property
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Animation</a></strong></dt>
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<dd>Introduced in Android 3.0 (API level 11), the property animation system lets you
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animate properties of any object, including ones that are not rendered to the screen. The system is
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extensible and lets you animate properties of custom types as well.</dd>
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<dt><strong><a href="{@docRoot}guide/topics/graphics/view-animation.html">View
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Animation</a></strong></dt>
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<dd>View Animation is the older system and can only be used for Views. It is relatively easy to
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setup and offers enough capabilities to meet many application's needs.</dd>
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</dl>
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<dt><strong><a href="{@docRoot}guide/topics/graphics/drawable-animation.html">Drawable
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Animation</a></strong></dt>
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<dd>Drawable animation involves displaying {@link android.graphics.drawable.Drawable} resources one
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after another, like a roll of film. This method of animation is useful if you want to animate
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things that are easier to represent with Drawable resources, such as a progression of bitmaps.</dd>
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<h3 id="graphics">2D and 3D Graphics</h3>
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<p>When writing an application, it's important to consider exactly what your graphical demands will be.
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Varying graphical tasks are best accomplished with varying techniques. For example, graphics and animations
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for a rather static application should be implemented much differently than graphics and animations
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for an interactive game. Here, we'll discuss a few of the options you have for drawing graphics
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on Android and which tasks they're best suited for.
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</p>
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<dl>
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<dt><strong><a href="{@docRoot}guide/topics/graphics/2d-graphics.html">Canvas and
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Drawables</a></strong></dt>
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<dd>Android provides a set of {@link android.view.View} widgets that provide general functionality
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for a wide array of user interfaces. You can also extend these widgets to modify the way they
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look or behave. In addition, you can do your own custom 2D rendering using the various drawing
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methods contained in the {@link android.graphics.Canvas} class or create {@link
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android.graphics.drawable.Drawable} objects for things such as textured buttons or frame-by-frame
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animations.</dd>
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<dt><strong><a href="{@docRoot}guide/topics/graphics/hardware-accel.html">Hardware
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Acceleration</a></strong></dt>
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<dd>Beginning in Android 3.0, you can hardware accelerate the majority of
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the drawing done by the Canvas APIs to further increase their performance.</dd>
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<dt><strong><a href="{@docRoot}guide/topics/graphics/opengl.html">OpenGL</a></strong></dt>
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<dd>Android supports OpenGL ES 1.0 and 2.0, with Android framework APIs as well as natively
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with the Native Development Kit (NDK). Using the framework APIs is desireable when you want to add a
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few graphical enhancements to your application that are not supported with the Canvas APIs, or if
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you desire platform independence and don't demand high performance. There is a performance hit in
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using the framework APIs compared to the NDK, so for many graphic intensive applications such as
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games, using the NDK is beneficial (It is important to note though that you can still get adequate
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performance using the framework APIs. For example, the Google Body app is developed entirely
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using the framework APIs). OpenGL with the NDK is also useful if you have a lot of native
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code that you want to port over to Android. For more information about using the NDK, read the
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docs in the <code>docs/</code> directory of the <a href="{@docRoot}tools/sdk/ndk/index.html">NDK
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download.</a></dd>
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</dl>
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