就Android平台而言，URI主要分三个部分：scheme, authority and path。其中authority又分为host和port。格式如下：
scheme://host:port/path
举个实际的例子：
content://com.example.project:200/folder/subfolder/etc
\---------/  \---------------------------/ \---/ \--------------------------/
scheme                 host               port        path
                \--------------------------------/
                          authority

现在大家应该知道data flag中那些属性的含义了吧，看下data flag
<data android:host="string"
      android:mimeType="string"
      android:path="string"
      android:pathPattern="string"
      android:pathPrefix="string"
      android:port="string"
      android:scheme="string" />
但是我们在程序中一般是不直接用URI来标识CP的，是的，正如我们通常见到的用定义的常量来标识。例如standard CP中的Contacts，我们就用Contacts.People.CONTENT_URI来标识Contacts CP中People这个表。那么要标识某个具体的人怎么办呢？ 这就用到了ContentUris.withAppendedId() 和 Uri.withAppendedPath()。例如我们要表示content://contacts/people/20，那么我们就可以用如下语句：
Uri uri = ContentUris.withAppendedId(People.CONTENT_URI, 20); 或者
Uri uri = Uri.withAppendedPath(People.CONTENT_URI, "20");

举些例子，如：

所有联系人的Uri： content://contacts/people

某个联系人的Uri: content://contacts/people/5

所有图片Uri: content://media/external

某个图片的Uri：content://media/external/images/media/4

下面是一些常用的Uri

显示网页:
  1. Uri uri = Uri.parse("http://www.google.com");
  2. Intent it = new Intent(Intent.ACTION_VIEW,uri);
  3. startActivity(it);

显示地图:
1. Uri uri = Uri.parse("geo:38.899533,-77.036476");
  2. Intent it = new Intent(Intent.Action_VIEW,uri);
  3. startActivity(it);

路径规划:
  1. Uri uri = Uri.parse("http://maps.google.com/maps?f=d&saddr=startLat%20startLng&daddr=endLat%20endLng&hl=en");
  2. Intent it = new Intent(Intent.ACTION_VIEW,URI);
  3. startActivity(it);

拨打电话:
调用拨号程序
  1. Uri uri = Uri.parse("tel:xxxxxx");
  2. Intent it = new Intent(Intent.ACTION_DIAL, uri);   
  3. startActivity(it);   
  1. Uri uri = Uri.parse("tel.xxxxxx");
  2. Intent it =new Intent(Intent.ACTION_CALL,uri);
  3. 要使用这个必须在配置文件中加入<uses-permission id="Android.permission.CALL_PHONE" />

发送SMS/MMS
调用发送短信的程序
  1. Intent it = new Intent(Intent.ACTION_VIEW);
  2. it.putExtra("sms_body", "The SMS text");
  3. it.setType("vnd.android-dir/mms-sms");
  4. startActivity(it);   
发送短信
  1. Uri uri = Uri.parse("smsto:0800000123");
  2. Intent it = new Intent(Intent.ACTION_SENDTO, uri);
  3. it.putExtra("sms_body", "The SMS text");
  4. startActivity(it);   
发送彩信
  1. Uri uri = Uri.parse("content://media/external/images/media/23");
  2. Intent it = new Intent(Intent.ACTION_SEND);
  3. it.putExtra("sms_body", "some text");
  4. it.putExtra(Intent.EXTRA_STREAM, uri);
  5. it.setType("image/png");
  6. startActivity(it);

发送Email
  1.
  2. Uri uri = Uri.parse("mailto:xxx@abc.com");
  3. Intent it = new Intent(Intent.ACTION_SENDTO, uri);
  4. startActivity(it);
  1. Intent it = new Intent(Intent.ACTION_SEND);
  2. it.putExtra(Intent.EXTRA_EMAIL, "me@abc.com");
  3. it.putExtra(Intent.EXTRA_TEXT, "The email body text");
  4. it.setType("text/plain");
  5. startActivity(Intent.createChooser(it, "Choose Email Client"));   
  1. Intent it=new Intent(Intent.ACTION_SEND);   
  2. String[] tos={"me@abc.com"};   
  3. String[] ccs={"you@abc.com"};   
  4. it.putExtra(Intent.EXTRA_EMAIL, tos);   
  5. it.putExtra(Intent.EXTRA_CC, ccs);   
  6. it.putExtra(Intent.EXTRA_TEXT, "The email body text");   
  7. it.putExtra(Intent.EXTRA_SUBJECT, "The email subject text");   
  8. it.setType("message/rfc822");   
  9. startActivity(Intent.createChooser(it, "Choose Email Client"));

添加附件
  1. Intent it = new Intent(Intent.ACTION_SEND);
  2. it.putExtra(Intent.EXTRA_SUBJECT, "The email subject text");
  3. it.putExtra(Intent.EXTRA_STREAM, "[url=]file:///sdcard/mysong.mp3[/url]");
  4. sendIntent.setType("audio/mp3");
  5. startActivity(Intent.createChooser(it, "Choose Email Client"));

播放多媒体
  1.   
  2. Intent it = new Intent(Intent.ACTION_VIEW);
  3. Uri uri = Uri.parse("[url=]file:///sdcard/song.mp3[/url]");
  4. it.setDataAndType(uri, "audio/mp3");
  5. startActivity(it);
  1. Uri uri = Uri.withAppendedPath(MediaStore.Audio.Media.INTERNAL_CONTENT_URI, "1");
  2. Intent it = new Intent(Intent.ACTION_VIEW, uri);
  3. startActivity(it);

Uninstall 程序
  1. Uri uri = Uri.fromParts("package", strPackageName, null);
  2. Intent it = new Intent(Intent.ACTION_DELETE, uri);
  3. startActivity(it);

//调用相册
public static final String MIME_TYPE_IMAGE_JPEG = "image/*";
public static final int ACTIVITY_GET_IMAGE = 0;
Intent getImage = new Intent(Intent.ACTION_GET_CONTENT); 
getImage.addCategory(Intent.CATEGORY_OPENABLE); 
getImage.setType(MIME_TYPE_IMAGE_JPEG);
startActivityForResult(getImage, ACTIVITY_GET_IMAGE);

//调用系统相机应用程序，并存储拍下来的照片
Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE); 
time = Calendar.getInstance().getTimeInMillis();
intent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(new File(Environment
.getExternalStorageDirectory().getAbsolutePath()+"/tucue", time + ".jpg")));
startActivityForResult(intent, ACTIVITY_GET_CAMERA_IMAGE);

uninstall apk
/**未测试
Uri uninstallUri = Uri.fromParts("package", "xxx", null);
returnIt = new Intent(Intent.ACTION_DELETE, uninstallUri);
*/
Uri packageURI = Uri.parse("package:"+wistatmap);   
Intent uninstallIntent = new Intent(Intent.ACTION_DELETE, packageURI);   
startActivity(uninstallIntent);

install apk
Uri installUri = Uri.fromParts("package", "xxx", null);
returnIt = new Intent(Intent.ACTION_PACKAGE_ADDED, installUri);
play audio
Uri playUri = Uri.parse("[url=]file:///sdcard/download/everything.mp3[/url]");
returnIt = new Intent(Intent.ACTION_VIEW, playUri);

//发送附件
Intent it = new Intent(Intent.ACTION_SEND);   
it.putExtra(Intent.EXTRA_SUBJECT, "The email subject text");   
it.putExtra(Intent.EXTRA_STREAM, "[url=]file:///sdcard/eoe.mp3[/url]");   
sendIntent.setType("audio/mp3");   
startActivity(Intent.createChooser(it, "Choose Email Client"));

//搜索应用
Uri uri = Uri.parse("market://search?q=pname:pkg_name");   
Intent it = new Intent(Intent.ACTION_VIEW, uri);   
startActivity(it);   
//where pkg_name is the full package path for an application

//进入联系人页面
Intent intent = new Intent();
intent.setAction(Intent.ACTION_VIEW);
intent.setData(People.CONTENT_URI);
startActivity(intent);

//查看指定联系人
Uri personUri = ContentUris.withAppendedId(People.CONTENT_URI, info.id);//info.id联系人ID
Intent intent = new Intent();
intent.setAction(Intent.ACTION_VIEW);
intent.setData(personUri);
startActivity(intent);