启动某些android应用程序的意图导致IllegalStateException

Question

似乎有两个问题，我遇到了问题。第一种情况是，当我启动时钟应用程序并完美工作时，这似乎是我推出大多数应用程序时的情况。

第二种情况是当我尝试启动诸如电话活动之类的活动时。当我去获取Intent时，getLaunchIntentForPackage（app.pname）返回null。有没有不同的方式来获得电话活动的意图，以便我可以在这种情况下启动它？

第三种情况是当我去启动诸如Camera活动的活动时。看起来我必须让我的androidManifest.xml文件中已经有Camera活动来启动它，但还有其他方法可以解决这个问题吗？我的应用程序具有可以从其UI中启动任何应用程序的能力，因此我无法将Android设备的每一项活动事先添加到我的清单文件中。谢谢！

的Java：

 Intent launchApp = getPackageManager().getLaunchIntentForPackage(app.pname); 

      System.out.println(Intent of " + appName + ": + " " +launchApp); 

      if(launchApp!=null){ 
       System.out.println("Permission granted to launch " + appName); 
       startActivity(launchApp); 
      } 

      else{ 

       System.out.println("Permission not granted to launch " + appName); 
      } 

的logcat：

 08-07 09:38:57.031: I/System.out(1056): Intent of Clock: Intent { act=android.intent.action.MAIN flg=0x10000000 cmp=com.htc.android.worldclock/.WorldClockTabControl } 
     08-07 09:38:57.041: I/System.out(1056): Permission granted to launch Clock 
     08-07 09:38:59.783: I/System.out(1056): Intent of Phone: null 
     08-07 09:38:59.783: I/System.out(1056): Permission not granted to launch Phone 
     08-07 09:39:10.564: I/System.out(1056): Intent of Camera: Intent { act=android.intent.action.MAIN flg=0x10000000 cmp=com.android.camera/com.android.internal.app.ResolverActivity } 
     08-07 09:39:10.574: I/System.out(1056): Permission granted to launch Camera 
     08-07 09:39:10.574: D/AndroidRuntime(1056): Shutting down VM 
     08-07 09:39:10.574: W/dalvikvm(1056): threadid=1: thread exiting with uncaught exception (group=0x4001d5a0) 
     08-07 09:39:10.614: E/AndroidRuntime(1056): FATAL EXCEPTION: main 
     08-07 09:39:10.614: E/AndroidRuntime(1056): java.lang.IllegalStateException: Could not execute method of the activity 
     08-07 09:39:10.614: E/AndroidRuntime(1056):  at android.view.View$1.onClick(View.java:2191) 
     08-07 09:39:10.614: E/AndroidRuntime(1056):  at android.view.View.performClick(View.java:2532) 
     08-07 09:39:10.614: E/AndroidRuntime(1056):  at android.view.View$PerformClick.run(View.java:9293) 
     08-07 09:39:10.614: E/AndroidRuntime(1056):  at android.os.Handler.handleCallback(Handler.java:587) 
     08-07 09:39:10.614: E/AndroidRuntime(1056):  at android.os.Handler.dispatchMessage(Handler.java:92) 
     08-07 09:39:10.614: E/AndroidRuntime(1056):  at android.os.Looper.loop(Looper.java:150) 
     08-07 09:39:10.614: E/AndroidRuntime(1056):  at android.app.ActivityThread.main(ActivityThread.java:4306) 
     08-07 09:39:10.614: E/AndroidRuntime(1056):  at java.lang.reflect.Method.invokeNative(Native Method) 
     08-07 09:39:10.614: E/AndroidRuntime(1056):  at java.lang.reflect.Method.invoke(Method.java:507) 
     08-07 09:39:10.614: E/AndroidRuntime(1056):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839) 
     08-07 09:39:10.614: E/AndroidRuntime(1056):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597) 
     08-07 09:39:10.614: E/AndroidRuntime(1056):  at dalvik.system.NativeStart.main(Native Method) 
     08-07 09:39:10.614: E/AndroidRuntime(1056): Caused by: java.lang.reflect.InvocationTargetException 
     08-07 09:39:10.614: E/AndroidRuntime(1056):  at   java.lang.reflect.Method.invokeNative(Native Method) 
     08-07 09:39:10.614: E/AndroidRuntime(1056):  at java.lang.reflect.Method.invoke(Method.java:507) 
     08-07 09:39:10.614: E/AndroidRuntime(1056):  at android.view.View$1.onClick(View.java:2186) 
     08-07 09:39:10.614: E/AndroidRuntime(1056):  ... 11 more 
     08-07 09:39:10.614: E/AndroidRuntime(1056): Caused by: android.content.ActivityNotFoundException: Unable to find explicit activity class {com.android.camera/com.android.internal.app.ResolverActivity}; have you declared this activity in your AndroidManifest.xml? 
     08-07 09:39:10.614: E/AndroidRuntime(1056):  at android.app.Instrumentation.checkStartActivityResult(Instrumentation.java:1565) 
     08-07 09:39:10.614: E/AndroidRuntime(1056):  at android.app.Instrumentation.execStartActivity(Instrumentation.java:1539) 
     08-07 09:39:10.614: E/AndroidRuntime(1056):  at android.app.Activity.startActivityForResult(Activity.java:2919) 
     08-07 09:39:10.614: E/AndroidRuntime(1056):  at android.app.Activity.startActivity(Activity.java:3025) 
     08-07 09:39:10.614: E/AndroidRuntime(1056):  at com.worklight.androidnativeapp.AndroidNativeApp.appClicked(AndroidNativeApp.java:284) 
     08-07 09:39:10.614: E/AndroidRuntime(1056):  ... 14 more 

Answer 1

How to launch the camera

How to launch the dialer

启动你需要知道包名的特定应用程序和类名

try{ 
    Intent i = new Intent(); 
    i.setClassName("com.example.app", "com.example.app.MainActivity"); 
    i.addFlags(Intent.FLAG_ACTIVITY_REORDER_TO_FRONT); 
    startActivity(e); 
}catch(ActivityNotFoundException e){ 
    e.printStackTrace(); 
}