Several ways to launch other apps in Android

1, know the name of the package to start and the activity to start:

Intent Intent = new Intent ();

/** the parameters of the following methods refer to the package name to start the application and the corresponding activity*/
ComponentName cpn= New ComponentName ("Com.ldm.demo", "com.ldm.demo.TextActivity");
Intent. SetComponent (CPN);
StartActivity (Intent);

2, only know the package name of the app:

Packagemanager Packagemanager = Getpackagemanager ();
Intent intent=new Intent ();
Intent =packagemanager.getlaunchintentforpackage ("PackageName");/**packagename refers to the package name to start the application */
if (intent==null) {
System.out.println ("APP not found!");
}
StartActivity (Intent);
}
}

3, know the package name to start and the activity app to start to start and pass the data:

2. ComponentName componentname = new ComponentName ("Com.ldm.demo", "com.ldm.demo.TestActivity");
4. Intent Intent = new Intent ();
   
6. Bundle bundle = new bundle ();
   
8. Bundle.putstring ("Data", data);
10. Intent.putextras (bundle);
    
12. Intent.setcomponent (componentname);
    
14. StartActivity (Intent);
    
16. 4, the case of unknown package name:
17. /** Gets the package name of the app in the phone and returns a list collection **/
    Public list<packageinfo> Getallapps () {
    list<packageinfo> apps = new arraylist<packageinfo> ();
    Packagemanager Packagemanager = This.getpackagemanager ();
    /** get all apps in your phone * /
    list<packageinfo> paklist = pmanager.getinstalledpackages (0);
    for (int i = 0; i < paklist.size (); i++) {
    PackageInfo Pak = (packageinfo) paklist.get (i);
    /** Determine if a non-system preinstalled application (greater than 0 is pre-installed for the system, less than or equal to 0 for non-system applications) */
    if ((Pak.applicationInfo.flags & Pak.applicationInfo.FLAG_SYSTEM) <= 0) {
    Apps.add (Pak);
                    }     
                }     
    return apps;
        }   
     Once you have the package name, you can start the app by getting the package name that you want to start:
    Public void Launchapp () {
    Packagemanager Packagemanager = This.getpackagemanager ();
    list<packageinfo> packages = Getallapps ();
    PackageInfo pa = null;
    for (int i=0;i<packages.size (); i++) {
    pa = packages.get (i);
    /** Get the application name * /
    String Applabel = Packagemanager.getapplicationlabel (pa.applicationinfo). toString ();
    /** Get Package name * /
    String apppackage = pa.packagename;
    log.d ("+i, applabel+" "+apppackage");
                }   
    Intent Intent = packagemanager.getlaunchintentforpackage ("Jp.co.johospace.jorte");
    startactivity (Intent);
            }   
    

Several ways to launch other apps in Android