【Android开发基础系列】Uri专题
1 URI简介
URI包含如下几个部分：
content://usrname:password@com.google.com:80/person/10
1、红色部分：访问资源的命名机制
2、绿色部分：存放资源的主机名，或称为authority
3、蓝色部分：资源本省的名称,由路径表示
2 URI类
二、URI类
Android的URI类提供了几个使用接口来处理一个URI路径
1、public static final Uri EMPTY
一个空的URI对象，相等于""
2、public abstract String getAuthority ()
获取URI的authority部分，即usrname:password@com.google.com:80
3、public abstract String getHost ()
获取URI的主机部分，即com.google.com
4、public abstract int getPort ()
获取URI的端口，即80
5、、public abstract String getScheme ()
获取URI的scheme，即content://
6、public abstract String getUserInfo ()
获取URI的用户信息，即usrname:password
3 UriMatcher类
三、UriMatcher类
android为URI提供了一个UriMatcher类，用来对URI进行各种匹配。其主要接口如下：
void addURI(String authority, String path, int code)
向该UriMatcher中添加一条匹配规则.authority如前所述；path为资源的路径，其中"*"可表示匹配任何字符，"#"表示匹配一个数字；code为当某一URI匹配该规则时，返回的匹配码
int match(Uri uri)
开始匹配一个URI，成功则返回前面设定的code，否则返回UriMatcher.NO_MATCH常量。
以下摘自android：
private static final int PEOPLE = 1;
private static final int PEOPLE_ID = 2;
private static final int PEOPLE_PHONES = 3;
private static final int PEOPLE_PHONES_ID = 4;
private static final int PEOPLE_CONTACTMETHODS = 7;
private static final int PEOPLE_CONTACTMETHODS_ID = 8;
private static final int DELETED_PEOPLE = 20;
private static final int PHONES = 9;
private static final int PHONES_ID = 10;
private static final int PHONES_FILTER = 14;
private static final int CONTACTMETHODS = 18;
private static final int CONTACTMETHODS_ID = 19;
private static final int CALLS = 11;
private static final int CALLS_ID = 12;
private static final int CALLS_FILTER = 15;
private static final UriMatcher sURIMatcher = new UriMatcher(UriMatcher.NO_MATCH);
static
{
sURIMatcher.addURI("contacts","people", PEOPLE);
sURIMatcher.addURI("contacts","people/#", PEOPLE_ID);
sURIMatcher.addURI("contacts","people/#/phones", PEOPLE_PHONES);
sURIMatcher.addURI("contacts","people/#/phones/#", PEOPLE_PHONES_ID);
sURIMatcher.addURI("contacts","people/#/contact_methods", PEOPLE_CONTACTMETHODS);
sURIMatcher.addURI("contacts","people/#/contact_methods/#", PEOPLE_CONTACTMETHODS_ID);
sURIMatcher.addURI("contacts","deleted_people", DELETED_PEOPLE);
sURIMatcher.addURI("contacts","phones", PHONES);
sURIMatcher.addURI("contacts","phones/filter/*", PHONES_FILTER);
sURIMatcher.addURI("contacts","phones/#", PHONES_ID);
sURIMatcher.addURI("contacts","contact_methods", CONTACTMETHODS);
sURIMatcher.addURI("contacts","contact_methods/#", CONTACTMETHODS_ID);
sURIMatcher.addURI("call_log","calls", CALLS);
sURIMatcher.addURI("call_log","calls/filter/*", CALLS_FILTER);
sURIMatcher.addURI("call_log","calls/#", CALLS_ID);
}
4 ContentUris类
四、ContentUris类
ContentUris类是android提供的又一个URI的工具类，其作用主要是操作使用"content://"的URI路径后面的ID部分。其主要接口如下：
1、static Uri.Builder
appendId(Uri.Builder builder, long id)
将一个id添加到URI的后面.
2、static long parseId(Uri contentUri)
获取URI后面的路径id.
3、static Uri withAppendedId(Uri contentUri, long id)
类似于appendId，同样是将id添加到URI的后面.
5 开发技巧
5.1 常用开发技巧
5.1.1 Uri转换
Uri pathUri = Uri.parse(path);
6 参考链接
android之ContentProvider和Uri详解
http://www.2cto.com/kf/201404/294406.html
Android通过Uri获取Bitmap对象
http://blog.sina.com.cn/s/blog_5de73d0b0100zfm8.html
(Good)Android之URI
http://blog.csdn.net/lxgwm2008/article/details/8710955
android file path问题
http://blog.csdn.net/competerh_programing/article/details/7306256
Android将"content://"类型的uri转为文件路径
http://blog.csdn.net/rickyfm/article/details/48448437
Android Volley框架的使用（一）
http://www.cnblogs.com/zyw-205520/p/4950357.html
Android Volley框架全面解析
