Android平台为多种常见媒体类型提供了内建的编码/解码支持，因而可以简单地向程序整合音频、视频和图像。要使用平台的媒体功能非常简单——同样只需使用意图-活动的机制，之后Android会处理其余的工作。
Android可以从多种数据源类型中播放音频和视频。可以播放存储在程序资源（原始资源 raw resource）中的音频或视频媒体文件，可以播放文件系统中的某一文件，可以播放经由网络的流数据。要让程序播放视频或音频，需使用MediaPlayer类。
如果移动设备硬件支持的话，平台也支持录制音频和视频。要录制音频或视频，需使用MediaRecorder类。注意，模拟器没有获取音频或视频的硬件，不过实际的移动设备通常会提供这些支持，可以通过MediaRecorder类使用。
要了解Android提供内建支持的媒体格式列表，参见附录“Android媒体格式”。
音频和视频播放
可以播放任意来源的媒体：原始资源、系统中的文件或是可用的网络（URL）。
仅可以通过标准输出设备播放音频数据；目前来说，就是至移动设备的扬声器或是蓝牙耳机。现在不能在通话音频中播放声音文件。
播放原始资源
最为常见的需求或许就是从自有程序中播放媒体（一般是声音）了吧。这很容易做到：
- 将声音（或其他媒体资源）文件放入工程的res/raw文件夹，Eclipse插件（或aapt）将会发现它并将其识别为R类可以引用的资源。
- 创建一个MediaPlayer的实例，用MediaPlayer.create引用该资源，之后调用实例的start()方法：
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<span style="color: #000000;"><span style="color: #800080;"> MediaPlayer</span> mp = <span style="color: #800080;">MediaPlayer</span>.create(context, R.raw.sound_file_1);</span> <span style="color: #000000;"> mp.start();</span> |
要停止播放，调用stop()。如果希望之后重放该媒体，就必须在再次调用start()之前reset()及prepare()该MediaPlayer对象。（create()在第一次使用时会调用prepare()。）
要暂停播放，调用pause()。在想要继续播放的时候调用start()。
播放文件或流
可以播放储存于文件系统中或位于网络URL的媒体文件：
- 使用new来创建一个新的MediaPlayer实例
- 以一个包含了要播放的文件的路径（文件地址或是URL）的字符串调用setDataSource()
- 首先prepare()之后start()该实例：
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<span style="color: #800080;">MediaPlayer</span> <span style="color: #000000;">mp =</span> <span style="color: #000080;">new</span> <span style="color: #800080;">MediaPlayer</span><span style="color: #000000;">();</span> <span style="color: #000000;">mp.setDataSource(PATH_TO_FILE);</span> <span style="color: #000000;"> mp.prepare();</span> <span style="color: #000000;"> mp.start();</span> |
stop()和pause()的工作方式同上。
注意：当引用的文件不存在时，IllegalArgumentException 和IOException 可能会在使用setDataSource()时被接收或传递。
注意：如果传递的是在线媒体文件的URL，该文件必须可以被逐步下载。
播放JET内容
Android平台包含了一个JET引擎，它允许在程序中添加与JET音频内容的播放控制交互。可以使用SDK附带的JetCreator授权程序创建JET内容的播放控制交互。要在程序中播放并管理JET内容，需要使用JetPlayer类。
关于JET理念的描述及使用JetCreator授权工具的使用说明，参见“JetCreator用户手册”。该工具在OS X和Windows平台下全功能可用，在Linux下所有的内容创建功能也都被支持，只是输入内容审查功能不被支持。
这里有一个如何从一个储存于SD卡的.jet文件中建立JET播放的例子：
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<span style="color: #000000;"><span style="color: #800080;">JetPlayer</span> myJet = <span style="color: #800080;">JetPlayer</span>.getJetPlayer();</span> <span style="color: #000000;">myJet.loadJetFile(<span style="color: #008000;">"/sdcard/level1.jet"</span>);</span> <span style="color: #000000;"><span style="color: #000080;">byte</span> segmentId = 0;</span> <span style="color: #993300;">// queue segment 5, repeat once, use General MIDI, transpose by -1 octave</span> <span style="color: #000000;">myJet.queueJetSegment(<span style="color: #008080;">5</span>, -<span style="color: #008080;">1</span>, <span style="color: #008080;">1</span>, -<span style="color: #008080;">1</span>, <span style="color: #008080;">0</span>, segmentId++);</span> <span style="color: #993300;">// queue segment 2</span> <span style="color: #000000;">myJet.queueJetSegment(<span style="color: #008080;">2</span>, -<span style="color: #008080;">1</span>, <span style="color: #008080;">0</span>, <span style="color: #008080;">0</span>, <span style="color: #008080;">0</span>, segmentId++);</span> <span style="color: #000000;">myJet.play();</span> |
SDK包含了一个程序范例——JetBoy——演示了如何使用JetPlayer创建游戏中的音乐音轨播放交互。它同时也展示了如何使用JET事件来同步音乐播放和游戏逻辑。该程序位于<sdk>/platforms/android-1.5/samples/JetBoy。
音频录制
通过设备录制音频要比播放音频/视频稍微复杂一些，不过其实也是相当简单：
- 使用new来创建android.media.MediaRecorder的一个新的实例
- 使用MediaRecorder.setAudioSource()来设置音频源。通常会使用MediaRecorder.AudioSource.MIC
- 使用MediaRecorder.setOutputFormat()来设置输出文件格式
- 使用MediaRecorder.setOutputFile()来设置输出文件名
- 使用MediaRecorder.setAudioEncoder()来设置音频编码
- 对MediaRecorder实例调用MediaRecorder.prepare()
- 调用MediaRecorder.start()以开始音频录制
- 调用MediaRecorder.stop()以结束音频录制
- 当不再需要MediaRecorder实例时，对其调用MediaRecorder.release()。建议调用MediaRecorder.release()来立即释放资源
范例：录制音频并播放录制的音频
下面的这个范例类演示了如何建立、开始及终止音频录制，之后播放录制的音频文件。
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<span style="color: #993300;">/*</span> <span style="color: #993300;"> * The application needs to have the permission to write to external storage</span> <span style="color: #993300;"> * if the output file is written to the external storage, and also the</span> <span style="color: #993300;"> * permission to record audio. These permissions must be set in the</span> <span style="color: #993300;"> * application's AndroidManifest.xml file, with something like:</span> <span style="color: #993300;"> *</span> <span style="color: #993300;"> * <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" /></span> <span style="color: #993300;"> * <uses-permission android:name="android.permission.RECORD_AUDIO" /></span> <span style="color: #993300;"> *</span> <span style="color: #993300;"> */</span> <span style="color: #000000;"><span style="color: #000080;">package</span> com.android.audiorecordtest;</span> <span style="color: #000000;"><span style="color: #000080;">import</span> android.app.<span style="color: #800080;">Activity</span>;</span> <span style="color: #000000;"><span style="color: #000080;">import</span> android.widget.<span style="color: #800080;">LinearLayout</span>;</span> <span style="color: #000000;"><span style="color: #000080;">import</span> android.os.<span style="color: #800080;">Bundle</span>;</span> <span style="color: #000000;"><span style="color: #000080;">import</span> android.os.<span style="color: #800080;">Environment</span>;</span> <span style="color: #000000;"><span style="color: #000080;">import</span> android.view.<span style="color: #800080;">ViewGroup</span>;</span> <span style="color: #000000;"><span style="color: #000080;">import</span> android.widget.<span style="color: #800080;">Button</span>;</span> <span style="color: #000000;"><span style="color: #000080;">import</span> android.view.<span style="color: #800080;">View</span>;</span> <span style="color: #000000;"><span style="color: #000080;">import</span> android.view.View.<span style="color: #800080;">OnClickListener</span>;</span> <span style="color: #000000;"><span style="color: #000080;">import</span> android.content.<span style="color: #800080;">Context</span>;</span> <span style="color: #000000;"><span style="color: #000080;">import</span> android.util.<span style="color: #800080;">Log</span>;</span> <span style="color: #000000;"><span style="color: #000080;">import</span> android.media.<span style="color: #800080;">MediaRecorder</span>;</span> <span style="color: #000000;"><span style="color: #000080;">import</span> android.media.<span style="color: #800080;">MediaPlayer</span>;</span> <span style="color: #000000;"><span style="color: #000080;">import</span> java.io.<span style="color: #800080;">IOException</span>;</span> <span style="color: #000000;"><span style="color: #000080;">public</span> <span style="color: #000080;">class</span> <span style="color: #800080;">AudioRecordTest</span> <span style="color: #000080;">extends</span> <span style="color: #800080;">Activity</span></span> <span style="color: #000000;">{</span> <span style="color: #000000;"><span style="color: #000080;"> private static</span> <span style="color: #000080;">final</span> <span style="color: #800080;">String</span> LOG_TAG = "AudioRecordTest";</span> <span style="color: #000000;"><span style="color: #000080;"> private</span> <span style="color: #000080;">static</span> <span style="color: #800080;">String</span> mFileName = <span style="color: #000080;">null</span>;</span> <span style="color: #000000;"><span style="color: #000080;"> private</span> <span style="color: #800080;">RecordButton</span> mRecordButton = <span style="color: #000080;">null</span>;</span> <span style="color: #000000;"><span style="color: #000080;"> private</span> <span style="color: #800080;">MediaRecorder</span> mRecorder = <span style="color: #000080;">null</span>;</span> <span style="color: #000000;"><span style="color: #000080;"> private</span> <span style="color: #800080;">PlayButton </span> mPlayButton = <span style="color: #000080;">null</span>;</span> <span style="color: #000000;"><span style="color: #000080;"> private</span> <span style="color: #800080;">MediaPlayer </span> mPlayer = <span style="color: #000080;">null</span>;</span> <span style="color: #000000;"><span style="color: #000080;"> private</span> <span style="color: #000080;">void</span> onRecord(<span style="color: #000080;">boolean</span> start) {</span> <span style="color: #000000;"><span style="color: #000080;"> if</span> (start) {</span> <span style="color: #000000;"> startRecording();</span> <span style="color: #000000;"> } <span style="color: #000080;">else</span> {</span> <span style="color: #000000;"> stopRecording();</span> <span style="color: #000000;"> }</span> <span style="color: #000000;"> }</span> <span style="color: #000000;"><span style="color: #000080;"> private</span> <span style="color: #000080;">void</span> onPlay(<span style="color: #000080;">boolean</span> start) {</span> <span style="color: #000000;"><span style="color: #000080;"> if</span> (start) {</span> <span style="color: #000000;"> startPlaying();</span> <span style="color: #000000;"> } <span style="color: #000080;">else</span> {</span> <span style="color: #000000;"> stopPlaying();</span> <span style="color: #000000;"> }</span> <span style="color: #000000;"> }</span> <span style="color: #000000;"><span style="color: #000080;"> private</span> <span style="color: #000080;">void</span> startPlaying() {</span> <span style="color: #000000;"> mPlayer = <span style="color: #000080;">new</span> <span style="color: #800080;">MediaPlayer</span>();</span> <span style="color: #000000;"><span style="color: #000080;"> try</span> {</span> <span style="color: #000000;"> mPlayer.setDataSource(mFileName);</span> <span style="color: #000000;"> mPlayer.prepare();</span> <span style="color: #000000;"> mPlayer.start();</span> <span style="color: #000000;"> } <span style="color: #000080;">catch</span> (<span style="color: #800080;">IOException</span> e) {</span> <span style="color: #000000;"><span style="color: #800080;"> Log</span>.e(LOG_TAG, <span style="color: #008000;">"prepare() failed"</span>);</span> <span style="color: #000000;"> }</span> <span style="color: #000000;"> }</span> <span style="color: #000000;"><span style="color: #000080;"> private</span> <span style="color: #000080;">void</span> stopPlaying() {</span> <span style="color: #000000;"> mPlayer.release();</span> <span style="color: #000000;"> mPlayer = <span style="color: #000080;">null</span>;</span> <span style="color: #000000;"> }</span> <span style="color: #000000;"><span style="color: #000080;"> private</span> <span style="color: #000080;">void</span> startRecording() {</span> <span style="color: #000000;"> mRecorder = <span style="color: #000080;">new</span> <span style="color: #800080;">MediaRecorder</span>();</span> <span style="color: #000000;"> mRecorder.setAudioSource(<span style="color: #800080;">MediaRecorder.AudioSource</span>.MIC);</span> <span style="color: #000000;"> mRecorder.setOutputFormat(<span style="color: #800080;">MediaRecorder.OutputFormat</span>.THREE_GPP);</span> <span style="color: #000000;"> mRecorder.setOutputFile(mFileName);</span> <span style="color: #000000;"> mRecorder.setAudioEncoder(<span style="color: #800080;">MediaRecorder.AudioEncoder</span>.AMR_NB);</span> <span style="color: #000000;"><span style="color: #000080;"> try</span> {</span> <span style="color: #000000;"> mRecorder.prepare();</span> <span style="color: #000000;"> } <span style="color: #000080;">catch</span> (<span style="color: #800080;">IOException</span> e) {</span> <span style="color: #000000;"><span style="color: #800080;"> Log</span>.e(LOG_TAG, <span style="color: #008000;">"prepare() failed"</span>);</span> <span style="color: #000000;"> }</span> <span style="color: #000000;"> mRecorder.start();</span> <span style="color: #000000;"> }</span> <span style="color: #000000;"><span style="color: #000080;"> private</span> <span style="color: #000080;">void</span> stopRecording() {</span> <span style="color: #000000;"> mRecorder.stop();</span> <span style="color: #000000;"> mRecorder.release();</span> <span style="color: #000000;"> mRecorder = <span style="color: #000080;">null</span>;</span> <span style="color: #000000;"> }</span> <span style="color: #000000;"><span style="color: #000080;"> class</span> <span style="color: #800080;">RecordButton</span> <span style="color: #000080;">extends</span> <span style="color: #800080;">Button</span> {</span> <span style="color: #000000;"><span style="color: #000080;"> boolean</span> mStartRecording = <span style="color: #000080;">true</span>;</span> <span style="color: #000000;"><span style="color: #800080;"> OnClickListener</span> clicker = <span style="color: #000080;">new</span> <span style="color: #800080;">OnClickListener</span>() {</span> <span style="color: #000000;"><span style="color: #000080;"> public</span> <span style="color: #000080;">void</span> onClick(<span style="color: #800080;">View</span> v) {</span> <span style="color: #000000;"> onRecord(mStartRecording);</span> <span style="color: #000000;"><span style="color: #000080;"> if</span> (mStartRecording) {</span> <span style="color: #000000;"> setText("Stop recording");</span> <span style="color: #000000;"> } <span style="color: #000080;">else</span> {</span> <span style="color: #000000;"> setText("Start recording");</span> <span style="color: #000000;"> }</span> <span style="color: #000000;"> mStartRecording = !mStartRecording;</span> <span style="color: #000000;"> }</span> <span style="color: #000000;"> };</span> <span style="color: #000000;"><span style="color: #000080;"> public</span> <span style="color: #800080;">RecordButton</span>(<span style="color: #800080;">Context</span> ctx) {</span> <span style="color: #000000;"><span style="color: #000080;"> super</span>(ctx);</span> <span style="color: #000000;"> setText(<span style="color: #008000;">"Start recording"</span>);</span> <span style="color: #000000;"> setOnClickListener(clicker);</span> <span style="color: #000000;"> }</span> <span style="color: #000000;"> }</span> <span style="color: #000000;"><span style="color: #000080;"> class</span> <span style="color: #800080;">PlayButton</span> <span style="color: #000080;">extends</span> <span style="color: #800080;">Button</span> {</span> <span style="color: #000000;"><span style="color: #000080;"> boolean</span> mStartPlaying = <span style="color: #000080;">true</span>;</span> <span style="color: #000000;"><span style="color: #800080;"> OnClickListener</span> clicker = <span style="color: #000080;">new</span> <span style="color: #800080;">OnClickListener</span>() {</span> <span style="color: #000000;"><span style="color: #000080;"> public</span> <span style="color: #000080;">void</span> onClick(<span style="color: #800080;">View</span> v) {</span> <span style="color: #000000;"> onPlay(mStartPlaying);</span> <span style="color: #000000;"><span style="color: #000080;"> if</span> (mStartPlaying) {</span> <span style="color: #000000;"> setText(<span style="color: #008000;">"Stop playing"</span>);</span> <span style="color: #000000;"> } <span style="color: #000080;">else</span> {</span> <span style="color: #000000;"> setText(<span style="color: #008000;">"Start playing"</span>);</span> <span style="color: #000000;"> }</span> <span style="color: #000000;"> mStartPlaying = !mStartPlaying;</span> <span style="color: #000000;"> }</span> <span style="color: #000000;"> };</span> <span style="color: #000000;"><span style="color: #000080;"> public</span> <span style="color: #800080;">PlayButton</span>(<span style="color: #800080;">Context</span> ctx) {</span> <span style="color: #000000;"><span style="color: #000080;"> super</span>(ctx);</span> <span style="color: #000000;"> setText(<span style="color: #008000;">"Start playing"</span>);</span> <span style="color: #000000;"> setOnClickListener(clicker);</span> <span style="color: #000000;"> }</span> <span style="color: #000000;"> }</span> <span style="color: #000000;"><span style="color: #000080;"> public</span> <span style="color: #800080;">AudioRecordTest</span>() {</span> <span style="color: #000000;"> mFileName = <span style="color: #800080;">Environment</span>.getExternalStorageDirectory().getAbsolutePath();</span> <span style="color: #000000;"> mFileName += <span style="color: #008000;">"/audiorecordtest.3gp"</span>;</span> <span style="color: #000000;"> }</span> <span style="color: #008080;"> @Override</span> <span style="color: #000000;"><span style="color: #000080;"> public</span> <span style="color: #000080;">void</span> onCreate(<span style="color: #800080;">Bundle</span> icicle) {</span> <span style="color: #000000;"><span style="color: #000080;"> super</span>.onCreate(icicle);</span> <span style="color: #000000;"><span style="color: #800080;"> LinearLayout</span> ll = <span style="color: #000080;">new</span> <span style="color: #800080;">LinearLayout</span>(<span style="color: #000080;">this</span>);</span> <span style="color: #000000;"> mRecordButton = <span style="color: #000080;">new</span> <span style="color: #800080;">RecordButton</span>(<span style="color: #000080;">this</span>);</span> <span style="color: #000000;"> ll.addView(mRecordButton,</span> <span style="color: #000000;"><span style="color: #000080;"> new</span> <span style="color: #800080;">LinearLayout.LayoutParams</span>(</span> <span style="color: #000000;"><span style="color: #800080;"> ViewGroup.LayoutParams</span>.WRAP_CONTENT,</span> <span style="color: #000000;"><span style="color: #800080;"> ViewGroup.LayoutParams</span>.WRAP_CONTENT,</span> <span style="color: #000000;"><span style="color: #008080;"> 0</span>));</span> <span style="color: #000000;"> mPlayButton = <span style="color: #000080;">new</span> <span style="color: #800080;">PlayButton</span>(<span style="color: #000080;">this</span>);</span> <span style="color: #000000;"> ll.addView(mPlayButton,</span> <span style="color: #000000;"><span style="color: #000080;"> new</span> <span style="color: #800080;">LinearLayout.LayoutParams</span>(</span> <span style="color: #000000;"><span style="color: #800080;"> ViewGroup.LayoutParams</span>.WRAP_CONTENT,</span> <span style="color: #000000;"><span style="color: #800080;"> ViewGroup.LayoutParams</span>.WRAP_CONTENT,</span> <span style="color: #000000;"><span style="color: #008080;"> 0</span>));</span> <span style="color: #000000;"> setContentView(ll);</span> <span style="color: #000000;"> }</span> <span style="color: #008080;"> @Override</span> <span style="color: #000000;"><span style="color: #000080;"> public</span> <span style="color: #000080;">void</span> onPause() {</span> <span style="color: #000000;"><span style="color: #000080;"> super</span>.onPause();</span> <span style="color: #000000;"><span style="color: #000080;"> if</span> (mRecorder != <span style="color: #000080;">null</span>) {</span> <span style="color: #000000;"> mRecorder.release();</span> <span style="color: #000000;"> mRecorder = <span style="color: #000080;">null</span>;</span> <span style="color: #000000;"> }</span> <span style="color: #000000;"><span style="color: #000080;"> if</span> (mPlayer != <span style="color: #000080;">null</span>) {</span> <span style="color: #000000;"> mPlayer.release();</span> <span style="color: #000000;"> mPlayer = <span style="color: #000080;">null</span>;</span> <span style="color: #000000;"> }</span> <span style="color: #000000;"> }</span> <span style="color: #000000;">}</span> |
本页部分内容根据Android Open Source Project创作并共享的内容修改，并在知识共享 署名2.5许可协议中所述条款的限制下使用。