Develop Reference

App Crashes when i try to login into facebook android

I dont know why my app crashes throwing a NPE when i click the facebook login button. I have added and checked all the necessary library files. but still it crashes. kindly help me.
My LogCat
05-29 13:28:58.770: E/AndroidRuntime(4161): FATAL EXCEPTION: main
05-29 13:28:58.770: E/AndroidRuntime(4161): java.lang.NullPointerException
05-29 13:28:58.770: E/AndroidRuntime(4161): at android.support.v4.content.LocalBroadcastManager.<init>(LocalBroadcastManager.java:110)
05-29 13:28:58.770: E/AndroidRuntime(4161): at android.support.v4.content.LocalBroadcastManager.getInstance(LocalBroadcastManager.java:102)
05-29 13:28:58.770: E/AndroidRuntime(4161): at com.facebook.Session.postActiveSessionAction(Session.java:1574)
05-29 13:28:58.770: E/AndroidRuntime(4161): at com.facebook.Session.setActiveSession(Session.java:971)
05-29 13:28:58.770: E/AndroidRuntime(4161): at com.facebook.Session.openActiveSession(Session.java:1126)
05-29 13:28:58.770: E/AndroidRuntime(4161): at com.facebook.Session.openActiveSession(Session.java:1035)
05-29 13:28:58.770: E/AndroidRuntime(4161): at com.trimex.amadora.FlipperRegister.intialiseFBLogin(FlipperRegister.java:398)
05-29 13:28:58.770: E/AndroidRuntime(4161): at com.trimex.amadora.FlipperRegister.onClick(FlipperRegister.java:292)
05-29 13:28:58.770: E/AndroidRuntime(4161): at android.view.View.performClick(View.java:4475)
05-29 13:28:58.770: E/AndroidRuntime(4161): at android.view.View$PerformClick.run(View.java:18786)
05-29 13:28:58.770: E/AndroidRuntime(4161): at android.os.Handler.handleCallback(Handler.java:730)
05-29 13:28:58.770: E/AndroidRuntime(4161): at android.os.Handler.dispatchMessage(Handler.java:92)
05-29 13:28:58.770: E/AndroidRuntime(4161): at android.os.Looper.loop(Looper.java:137)
05-29 13:28:58.770: E/AndroidRuntime(4161): at android.app.ActivityThread.main(ActivityThread.java:5454)
05-29 13:28:58.770: E/AndroidRuntime(4161): at java.lang.reflect.Method.invokeNative(Native Method)
05-29 13:28:58.770: E/AndroidRuntime(4161): at java.lang.reflect.Method.invoke(Method.java:525)
05-29 13:28:58.770: E/AndroidRuntime(4161): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1187)
05-29 13:28:58.770: E/AndroidRuntime(4161): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1003)
05-29 13:28:58.770: E/AndroidRuntime(4161): at dalvik.system.NativeStart.main(Native Method)

So you have the broadcast which when broadcasts, the receiver listens.
But what if the thing you want to respond to this broadcast is Null on the course as soon as it's broadcast.
So check your activity or fragment where you defined your listener if its instantiated before the call.

android arduino usb communication

I'm trying to establish communication between Arduino UNO R3 and Galaxy SII on Android 4.1 cross usb. The code sample i am following i here: http://androidgurusolutions.blogspot.com/2012/07/arduino-adk-board-blink-led-with-your.html . Unfortunately, i am getting this message 'app has stopped' and here is LogCat error
LogCat:
E/AndroidRuntime(535): FATAL EXCEPTION: main
E/AndroidRuntime(535): java.lang.NoClassDefFoundError: com.android.future.usb.UsbManager
E/AndroidRuntime(535): at com.example.mypro.MainActivity.onCreate(MainActivity.java:123)
E/AndroidRuntime(535): at android.app.Activity.performCreate(Activity.java:4465)
E/AndroidRuntime(535): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1049)
E/AndroidRuntime(535): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1919)
E/AndroidRuntime(535): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1980)
E/AndroidRuntime(535):at android.app.ActivityThread.access$600(ActivityThread.java:122)
E/AndroidRuntime(535):at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1146)
E/AndroidRuntime(535):at android.os.Handler.dispatchMessage(Handler.java:99)
E/AndroidRuntime(535):at android.os.Looper.loop(Looper.java:137)
E/AndroidRuntime(535):at android.app.ActivityThread.main(ActivityThread.java:4340)
E/AndroidRuntime(535):at java.lang.reflect.Method.invokeNative(Native Method)
E/AndroidRuntime(535):at java.lang.reflect.Method.invoke(Method.java:511)
E/AndroidRuntime(535):at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
E/AndroidRuntime(535):at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
E/AndroidRuntime(535):at dalvik.system.NativeStart.main(Native Method)
please can anybody help me. thanks in advance.....

Exception after clicked and closed banner

I have DoubleClick banners in 'MainActivity'(A) and in 'FindActivity'(B).
When I click banner in A - it opens and I'm pressing 'back' button - A appears again and works fine.
When click banner in B - it opens and I'm pressing 'back' - B did not appears. LogCat says:
05-29 16:38:27.542: E/AndroidRuntime(661): FATAL EXCEPTION: main
05-29 16:38:27.542: E/AndroidRuntime(661): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.my.myapp/com.my.myapp.FindActivity}: java.lang.NullPointerException
05-29 16:38:27.542: E/AndroidRuntime(661): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1651)
05-29 16:38:27.542: E/AndroidRuntime(661): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1667)
05-29 16:38:27.542: E/AndroidRuntime(661): at android.app.ActivityThread.access$1500(ActivityThread.java:117)
05-29 16:38:27.542: E/AndroidRuntime(661): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:935)
05-29 16:38:27.542: E/AndroidRuntime(661): at android.os.Handler.dispatchMessage(Handler.java:99)
05-29 16:38:27.542: E/AndroidRuntime(661): at android.os.Looper.loop(Looper.java:130)
05-29 16:38:27.542: E/AndroidRuntime(661): at android.app.ActivityThread.main(ActivityThread.java:3687)
05-29 16:38:27.542: E/AndroidRuntime(661): at java.lang.reflect.Method.invokeNative(Native Method)
05-29 16:38:27.542: E/AndroidRuntime(661): at java.lang.reflect.Method.invoke(Method.java:507)
05-29 16:38:27.542: E/AndroidRuntime(661): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:842)
05-29 16:38:27.542: E/AndroidRuntime(661): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:600)
05-29 16:38:27.542: E/AndroidRuntime(661): at dalvik.system.NativeStart.main(Native Method)
05-29 16:38:27.542: E/AndroidRuntime(661): Caused by: java.lang.NullPointerException
05-29 16:38:27.542: E/AndroidRuntime(661): at com.my.myapp.FindActivity.onCreate(FindActivity.java:125)
05-29 16:38:27.542: E/AndroidRuntime(661): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
05-29 16:38:27.542: E/AndroidRuntime(661): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1615)
05-29 16:38:27.542: E/AndroidRuntime(661): ... 11 more
I've put breakpoint at line 125. Surprise - LogCat show exception without reaching breakpoint.
Code in onCreate is:
super.onCreate(savedInstanceState);//line124
m_current = MyApp.sInstance.GetName();//line 125 ========
Update
sInstance is App singleton.
added correct log copy
Update2
Bigger stack trace provided

gralloc_goldfish(634): Emulator without GPU emulation detected

I am using android SDK 4.0.3 and I'm trying to run a simple program in which I'm trying to switch from one page to another page using an Intent (By passing intent object as: Intent intent = new Intent(getApplicationContext(),SecondActivity.class);
startActivity(intent); )
[Also, I have 3GB RAM]
but when I run the program it gives something like this in DDMS:
01-23 01:58:23.892: D/gralloc_goldfish(634): Emulator without GPU emulation detected.
01-23 01:58:45.482: D/AndroidRuntime(634): Shutting down VM
01-23 01:58:45.492: W/dalvikvm(634): threadid=1: thread exiting with uncaught exception (group=0x409c01f8)
01-23 01:58:45.532: E/AndroidRuntime(634): FATAL EXCEPTION: main
01-23 01:58:45.532: E/AndroidRuntime(634): android.content.ActivityNotFoundException:
Unable to find explicit activity class {com.example.actionbar_demo/com.example.actionbar_demo.SecondActivity}; have you declared this activity in your AndroidManifest.xml?
01-23 01:58:45.532: E/AndroidRuntime(634): at android.app.Instrumentation.checkStartActivityResult(Instrumentation.java:1508)
01-23 01:58:45.532: E/AndroidRuntime(634): at android.app.Instrumentation.execStartActivity(Instrumentation.java:1384)
01-23 01:58:45.532: E/AndroidRuntime(634): at android.app.Activity.startActivityForResult(Activity.java:3190)
01-23 01:58:45.532: E/AndroidRuntime(634): at com.example.actionbar_demo.Actionbar_demoActivity$1.onClick(Actionbar_demoActivity.java:23)
01-23 01:58:45.532: E/AndroidRuntime(634): at android.view.View.performClick(View.java:3511)
01-23 01:58:45.532: E/AndroidRuntime(634): at android.view.View$PerformClick.run(View.java:14105)
01-23 01:58:45.532: E/AndroidRuntime(634): at android.os.Handler.handleCallback(Handler.java:605)
01-23 01:58:45.532: E/AndroidRuntime(634): at android.os.Handler.dispatchMessage(Handler.java:92)
01-23 01:58:45.532: E/AndroidRuntime(634): at android.os.Looper.loop(Looper.java:137)
01-23 01:58:45.532: E/AndroidRuntime(634): at android.app.ActivityThread.main(ActivityThread.java:4424)
01-23 01:58:45.532: E/AndroidRuntime(634): at java.lang.reflect.Method.invokeNative(Native Method)
01-23 01:58:45.532: E/AndroidRuntime(634): at java.lang.reflect.Method.invoke(Method.java:511)
01-23 01:58:45.532: E/AndroidRuntime(634): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
01-23 01:58:45.532: E/AndroidRuntime(634): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
01-23 01:58:45.532: E/AndroidRuntime(634): at dalvik.system.NativeStart.main(Native Method)
01-23 01:58:49.173: I/Process(634): Sending signal. PID: 634 SIG: 9

If you're worried about the:
Emulator without GPU emulation detected.
I wouldn't be. Given that a cursory search of the net turns it up quite a bit, and it's not related to the specific problems being discussed, I'd say it's just an indication that your emulator simply doesn't emulate the GPU. It's unlikely to be a problem.
That's supported by the fact it's a debug message (not even a warning, let alone an error) and also that there's a big 42-second gap between that and your actual problem.
The actual problem seems to be indicated by the line:
01-23 01:58:45.532: E/AndroidRuntime(634):
android.content.ActivityNotFoundException: Unable to find explicit activity
class {com.example.actionbar_demo/com.example.actionbar_demo.SecondActivity};
have you declared this activity in your AndroidManifest.xml?
So I have to ask: have you declared this activity in your AndroidManifest.xml?

Google API MapView OutOfMemory after setting the MapView to specific width and height

i searched for this Problem, and i found some stackoverflow Questions about the same but without any idea how to resolve the problem.
I created an activity and i want to add a really small mapview (like 140w X 70h). It is only to show a small preview of where the place is. When you click this little mapview you get a new inflate to a new activity with the hole map.
MapView:
<com.google.android.maps.MapView android:id="#+id/mapview"
android:layout_width="140dip"
android:layout_height="80dip"
android:layout_below="#id/attributes"
android:layout_alignParentRight="true"
android:apiKey="****"
android:paddingBottom="60dp"/>
LogCat:
05-30 14:34:53.758: ERROR/dalvikvm(1608): Out of memory: Heap Size=4039KB, Allocated=2768KB, Bitmap Size=625KB
05-30 14:34:53.758: DEBUG/AndroidRuntime(1608): Shutting down VM
05-30 14:34:53.758: WARN/dalvikvm(1608): threadid=1: thread exiting with uncaught exception (group=0x400259f8)
05-30 14:34:53.768: ERROR/AndroidRuntime(1608): FATAL EXCEPTION: main
05-30 14:34:53.768: ERROR/AndroidRuntime(1608): java.lang.OutOfMemoryError
05-30 14:34:53.768: ERROR/AndroidRuntime(1608): at com.google.googlenav.map.Map.resize(Unknown Source)
05-30 14:34:53.768: ERROR/AndroidRuntime(1608): at com.google.android.maps.MapView.onMeasure(MapView.java:554)
05-30 14:34:53.768: ERROR/AndroidRuntime(1608): at android.view.View.measure(View.java:8172)
05-30 14:34:53.768: ERROR/AndroidRuntime(1608): at android.widget.RelativeLayout.measureChildHorizontal(RelativeLayout.java:578)
05-30 14:34:53.768: ERROR/AndroidRuntime(1608): at android.widget.RelativeLayout.onMeasure(RelativeLayout.java:362)
05-30 14:34:53.768: ERROR/AndroidRuntime(1608): at android.view.View.measure(View.java:8172)
05-30 14:34:53.768: ERROR/AndroidRuntime(1608): at android.widget.ScrollView.measureChildWithMargins(ScrollView.java:989)
05-30 14:34:53.768: ERROR/AndroidRuntime(1608): at android.widget.FrameLayout.onMeasure(FrameLayout.java:245)
05-30 14:34:53.768: ERROR/AndroidRuntime(1608): at android.widget.ScrollView.onMeasure(ScrollView.java:286)
05-30 14:34:53.768: ERROR/AndroidRuntime(1608): at android.view.View.measure(View.java:8172)
05-30 14:34:53.768: ERROR/AndroidRuntime(1608): at android.widget.RelativeLayout.measureChildHorizontal(RelativeLayout.java:578)
05-30 14:34:53.768: ERROR/AndroidRuntime(1608): at android.widget.RelativeLayout.onMeasure(RelativeLayout.java:362)
05-30 14:34:53.768: ERROR/AndroidRuntime(1608): at android.view.View.measure(View.java:8172)
05-30 14:34:53.768: ERROR/AndroidRuntime(1608): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3140)
05-30 14:34:53.768: ERROR/AndroidRuntime(1608): at android.widget.FrameLayout.onMeasure(FrameLayout.java:245)
05-30 14:34:53.768: ERROR/AndroidRuntime(1608): at android.view.View.measure(View.java:8172)
05-30 14:34:53.768: ERROR/AndroidRuntime(1608): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3140)
05-30 14:34:53.768: ERROR/AndroidRuntime(1608): at android.widget.FrameLayout.onMeasure(FrameLayout.java:245)
05-30 14:34:53.768: ERROR/AndroidRuntime(1608): at android.view.View.measure(View.java:8172)
05-30 14:34:53.768: ERROR/AndroidRuntime(1608): at android.view.ViewRoot.performTraversals(ViewRoot.java:805)
05-30 14:34:53.768: ERROR/AndroidRuntime(1608): at android.view.ViewRoot.handleMessage(ViewRoot.java:1744)
05-30 14:34:53.768: ERROR/AndroidRuntime(1608): at android.os.Handler.dispatchMessage(Handler.java:99)
05-30 14:34:53.768: ERROR/AndroidRuntime(1608): at android.os.Looper.loop(Looper.java:144)
05-30 14:34:53.768: ERROR/AndroidRuntime(1608): at android.app.ActivityThread.main(ActivityThread.java:4937)
05-30 14:34:53.768: ERROR/AndroidRuntime(1608): at java.lang.reflect.Method.invokeNative(Native Method)
05-30 14:34:53.768: ERROR/AndroidRuntime(1608): at java.lang.reflect.Method.invoke(Method.java:521)
05-30 14:34:53.768: ERROR/AndroidRuntime(1608): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
05-30 14:34:53.768: ERROR/AndroidRuntime(1608): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
05-30 14:34:53.768: ERROR/AndroidRuntime(1608): at dalvik.system.NativeStart.main(Native Method)
this is the error. When i use fill_parent it works, but i dont want a mapview with fill_parent.
Maybe you guys know another way to get a preview small image of the current (or given) position on the map as image.
Isn't it possible to show a small mapview ?
thanks

If you just want to show a static map without interaction I recommend the static map api from google. You can define markers, the center, the size and some labels and it returns a generated image that can be easily shown inside a ImageView. The benefit of this: You don't have to invoke a complete MapView for just a small map image. No overhead of memory or user interaction. Perfect for the scenario you have.