Uses-permission and permission detailed

1.<uses-permission>:

Official Description:

protected by a permission, it must declare the IT requires that permission with a  <uses-permission>  

Permission by checking the authorities so signed the application ' s certificates and, in some cases, asking the user. If the permission is granted,
The application is able to use the protected features. If not, it attempts to access those features would simply fail without any notification to the user.

If an application needs to access a permission protected feature, the app must declare its required permissions in manifest with the <uses-permission> node. When the application is installed on the device,

The installer will decide whether to grant the permission it declares, which sometimes asks the user. If the permission is granted, the app can use the protected attribute, otherwise the access fails and the user is not notified.

Note: It is not necessary to call other applications to declare <uses-permission>, and sometimes even call the components of the program you are applying to declare!!! (The following example will be said)

2. <permission>:

New permission is declared with the  <permission>  

An application can also use permissions to protect its own components, which can be defined using the Android system or other application-defined or application-defined permissions, if you want to define a new permission,

can be <permission> defined with a node. As follows:

<permission android:description= "string resource"  android:icon= "drawable resource"   Android:label= "string resource"  android:name= "string"  android:permissiongroup= " String "  android:protectionlevel=[" Normal "| "Dangerous" |        " Signature "| "Signatureorsystem"]/>

For example, a activity could be protected as follows:

<Manifest. . . >  <PermissionAndroid:name= "Com.example.project.DEBIT_ACCT" . . . />  <uses-permissionAndroid:name= "Com.example.project.DEBIT_ACCT" />  . . .  <Application. . .>    <ActivityAndroid:name= "Com.example.project.FreneticActivity"android:permission= "Com.example.project.DEBIT_ACCT"          . . . >      . . .    </Activity>  </Application></Manifest>

 This example, the DEBIT_ACCT permission are not only declared  with the <permission> element, it is also requested with the  <uses-permission>element.
 for protected
<permission> element. However, it would still has been necessary to request their use with  <uses-permission>.

Note that in this example, DEBIT_ACCT this permission is not only declared in <permission>, but also declared in <uses-permission>, in order to start the protected activity in other components of the application ，

It is necessary to declare DEBIT_ACCT in <uses-permission>, even if this protection is added to the application itself. (This confirms the 1th said above).

Note that if the added permission is defined elsewhere, there is no need to declare the <permission> again, but still use <uses-permission> to declare this permission.

Reference:

Http://developer.android.com/guide/topics/manifest/manifest-intro.html#perms

http://berdy.iteye.com/blog/1782854

http://blog.csdn.net/lilu_leo/article/details/6940941

Uses-permission and permission detailed