public class UriMatcher
extends Object
| java.lang.Object | |
| android.content.UriMatcher | |
工具类有助于匹配内容提供者中的URI。
要使用这个类,建立一个UriMatcher对象树。 例如:
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);
}
从API级别JELLY_BEAN_MR2开始,路径可以JELLY_BEAN_MR2斜杠开始。 例如:
sURIMatcher.addURI("contacts", "/people", PEOPLE);
然后,当您需要与URI进行匹配时,请致电match(Uri) ,提供您已获得的URL。 您可以使用结果来构建查询,返回一个类型,插入或删除一行或任何您需要的内容,而无需重复所有您需要的if-else逻辑。 例如:
public String getType(Uri url)
{
int match = sURIMatcher.match(url);
switch (match)
{
case PEOPLE:
return "vnd.android.cursor.dir/person";
case PEOPLE_ID:
return "vnd.android.cursor.item/person";
... snip ...
return "vnd.android.cursor.dir/snail-mail";
case PEOPLE_ADDRESS_ID:
return "vnd.android.cursor.item/snail-mail";
default:
return null;
}
}
instead of:
public String getType(Uri url)
{
List
pathSegments = url.getPathSegments();
if (pathSegments.size() >= 2) {
if ("people".equals(pathSegments.get(1))) {
if (pathSegments.size() == 2) {
return "vnd.android.cursor.dir/person";
} else if (pathSegments.size() == 3) {
return "vnd.android.cursor.item/person";
... snip ...
return "vnd.android.cursor.dir/snail-mail";
} else if (pathSegments.size() == 3) {
return "vnd.android.cursor.item/snail-mail";
}
}
}
return null;
}
常量(Constants) |
|
|---|---|
int |
NO_MATCH |
Public constructors |
|
|---|---|
UriMatcher(int code) 创建URI树的根节点。 |
|
公共方法(Public methods) |
|
|---|---|
void |
addURI(String authority, String path, int code) 添加要匹配的URI,以及匹配此URI时返回的代码。 |
int |
match(Uri uri) 尝试匹配URL中的路径。 |
继承方法(Inherited methods) |
|
|---|---|
java.lang.Object
|
|
UriMatcher (int code)
创建URI树的根节点。
| 参数(Parameters) | |
|---|---|
code |
int: the code to match for the root URI |
void addURI (String authority, String path, int code)
添加要匹配的URI,以及匹配此URI时返回的代码。 URI节点可以是完全匹配字符串,与任何文本匹配的标记“*”或仅匹配数字的标记“#”。
从API级别 JELLY_BEAN_MR2 ,此方法将接受路径中的前导斜杠。
| 参数(Parameters) | |
|---|---|
authority |
String: the authority to match |
path |
String: the path to match. * may be used as a wild card for any text, and # may be used as a wild card for numbers. |
code |
int: the code that is returned when a URI is matched against the given components. Must be positive. |
int match (Uri uri)
尝试匹配URL中的路径。
| 参数(Parameters) | |
|---|---|
uri |
Uri: The url whose path we will match against. |
| 返回(Returns) | |
|---|---|
int |
The code for the matched node (added using addURI), or -1 if there is no matched node. |