android Intent匹配，自定义action data category

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public Intent setAction (String action)

Added in API level 1
Set the general action to be performed.

Parameters
action	An action name, such as ACTION_VIEW. Application-specific actions should be prefixed with the vendor's package name.
Returns
Returns the same Intent object, for chaining multiple calls into a single statement.

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public Intent setData (Uri data)

Added in API level 1
Set the data this intent is operating on. This method automatically clears any type that was previously set by setType(String) or setTypeAndNormalize(String).

Note: scheme matching in the Android framework is case-sensitive, unlike the formal RFC. As a result, you should always write your Uri with a lower case scheme, or use normalizeScheme() or setDataAndNormalize(Uri) to ensure that the scheme is converted to lower case.

Parameters
data	The Uri of the data this intent is now targeting.
Returns
Returns the same Intent object, for chaining multiple calls into a single statement.

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public Intent addCategory (String category)

Added in API level 1
Add a new category to the intent. Categories provide additional detail about the action the intent performs. When resolving an intent, only activities that provide all of the requested categories will be used.

Parameters
category	The desired category. This can be either one of the predefined Intent categories, or a custom category in your own namespace.
Returns
Returns the same Intent object, for chaining multiple calls into a single statement.

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Only three aspects of an Intent object are consulted when the object is tested against an intent filter:

action 
data (both URI and data type) 
category

The extras and flags play no part in resolving which component receives an intent.

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In principle, therefore, an Intent object with no categories should always pass this test, regardless of what's in the filter.

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 That's mostly true. However, with one exception, Android treats all implicit intents passed to startActivity() 

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as if they contained at least one category: "android.intent.category.DEFAULT" (the CATEGORY_DEFAULT constant). 

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Therefore, activities that are willing to receive implicit intents must include "android.intent.category.DEFAULT" 

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in their intent filters. (Filters with "android.intent.action.MAIN" and "android.intent.category.LAUNCHER" settings are the exception. 

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They mark activities that begin new tasks and that are represented on the launcher screen.

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 They can include "android.intent.category.DEFAULT" in the list of categories, but don't need to.)