Android Packagemanager Simple Introduction

Packagemanager related

This API is an encapsulation of all data structures based on loading information, including the following features:

Install, uninstall application query permission Related Information

Query application related information (application,activity,receiver,service,provider and corresponding attributes, etc.)

Querying installed Apps

Add, remove permission

Clear user data, cache, code snippets, etc.

/** * Packagemanager: * This API is an encapsulation of all data structures based on loading information, including the following features: * Install, uninstall application query permission related information query application related * information (APPLICATION,AC Tivity,receiver,service,provider and corresponding attributes, etc.) * Query installed apps Add, remove permission clear user data, cache, code snippets and other non-query related APIs require specific permissions. * Mainly includes information about the app packages installed on the current device * For example: Get information on Installed applications */private hashmap<string, string> installpackagesinfo () {// Gets the Packagemanager object Packagemanager Packagemanager = This.getpackagemanager ();/*getinstalledapplications Returns the collection of app packages installed on the current device * ApplicationInfo corresponding to the application label in Androidmanifest.xml. It is able to obtain the corresponding information of the application */list<applicationinfo> Applicationinfos = Packagemanager.getinstalledapplications ( 0); hashmap<string, string> resultmap = new hashmap<string, string> ();iterator<applicationinfo> iterator = Applicationinfos.iterator (); while (Iterator.hasnext ()) {ApplicationInfo applicationinfo = Iterator.next (); String packagename = applicationinfo.packagename;//Package name string Packagelabel = Packagemanager.getapplicationlabel ( ApplicationInfo). toString ();//Get LabelresuLtmap.put (Packagelabel, PackageName);} return resultmap;}

In addition to the Packagemanager class, we have found several very interesting methods.

Xmlresourceparse getXml (String packagename,int resid,applicationinfo AppInfo) is able to load an XML file from the specified package.