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getFloatArray is not receiving array

I'm working with a list:
List<Float> subjects = Arrays.asList(0f,0f,0f,0f,0f,0f);
List<Float> question9 = Arrays.asList(0f,0f);
And I want to put send it to another activity using Intent like this:
Intent iQuizz= new Intent(BachelorsResults.this, Results.class);
iQuizz.putExtra(BACHELOR, spinner.getSelectedItem().toString());
iQuizz.putExtra(QUESTION_9, question9.toArray());
iQuizz.putExtra(FAILED_SUBJECTS, subjects.toArray());
BachelorsResults.this.startActivity(iQuizz);
In the another activity I'm trying to receive float values:
Bundle extras = getIntent().getExtras();
float[] q9= extras.getFloatArray(QUESTION_9);
float[] fSubjects= extras.getFloatArray(FAILED_SUBJECTS);
But once I start this second activiy it launchs this Exception:
3-05 15:30:28.221 24640-24640/citrapp.exatec E/AndroidRuntime: FATAL EXCEPTION: main
Process: citrapp.exatec, PID: 24640
java.lang.RuntimeException: Unable to start activity ComponentInfo{citrapp.exatec/citrapp.exatec.Resultados}: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String java.lang.Object.toString()' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2426)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2490)
at android.app.ActivityThread.access$900(ActivityThread.java:154)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1354)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5443)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:728)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String java.lang.Object.toString()' on a null object reference
at citrapp.exatec.Resultados.onCreate(Resultados.java:85)
at android.app.Activity.performCreate(Activity.java:6259)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1130)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2379)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2490) 
at android.app.ActivityThread.access$900(ActivityThread.java:154) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1354) 
at android.os.Handler.dispatchMessage(Handler.java:102) 
at android.os.Looper.loop(Looper.java:148) 
at android.app.ActivityThread.main(ActivityThread.java:5443) 
at java.lang.reflect.Method.invoke(Native Method) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:728) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618) 
Somehow when I pass them to the another activity, float arrays become nulls, because I test extras.getFloatArray inside the first activity and it shows the content, but in the second activity it doesn't. If somebody could help me would be awesome..
Thanks!

Try replacing getIntent().getExtras() with getIntent().getFloatArrayExtra().

android - Short sounds on MediaPlayer throw NullPointerException

I have encountered a problem in which when ever I use
final MediaPlayer tick = MediaPlayer.create(getApplicationContext(), R.raw.tick);
tick.start();// tick is a short .mp3 file
in my app, no matter where, I get:
java.lang.NullPointerException: Attempt to invoke virtual method 'void android.media.MediaPlayer.start()' on a null object reference
at com.a.aar.MainActivity.onClicks(MainActivity.java:123)
at com.a.aar.MainActivity$2.onClick(MainActivity.java:97)
at android.view.View.performClick(View.java:5204)
at android.view.View$PerformClick.run(View.java:21153)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5417)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
But, whenever I use a slightly shorter sound effect, the app runs great.(I need a short sound because I want a lot of sounds coming fast and so the sounds will not stop)
What is the reason to this error and how can I solve it?

java.lang.NullPointerException: Attempt to read from field 'long org.opencv.core.Mat.nativeObj' on a null object reference

I am new to openCV and android. I am trying to load an image from Resources using bitmap and process the image using open CV. It gave me this error:
java.lang.NullPointerException:
Attempt to read from field 'long org.opencv.core.Mat.nativeObj' on a null object reference
Code:
Bitmap bm = BitmapFactory.decodeResource(getResources(),R.drawable.a1);
((ImageView)findViewById(R.id.imageView)).setImageBitmap(bm);
Mat trainImage = new Mat(bm.getHeight(),bm.getWidth(),CvType.CV_32S);
Utils.bitmapToMat(bm,trainImage);
if(trainImage.empty()){
Log.e(TAG,"Empty image");
}
else{
Log.e(TAG,"Image Loaded");
}
Imgproc.cvtColor(trainImage, trainGray, Imgproc.COLOR_RGBA2GRAY);
Here is the Exception message:
E/SVM: Image Loaded
D/AndroidRuntime: Shutting down VM
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.pragyan.facefeatures, PID: 3308
java.lang.NullPointerException: Attempt to read from field 'long org.opencv.core.Mat.nativeObj' on a null object reference
at org.opencv.imgproc.Imgproc.cvtColor(Imgproc.java:1724)
at com.example.pragyan.facefeatures.ExtractFeature.trainSvm(ExtractFeature.java:242)
at com.example.pragyan.facefeatures.ExtractFeature.onOptionsItemSelected(ExtractFeature.java:313)
at android.app.Activity.onMenuItemSelected(Activity.java:2885)
at android.support.v4.app.FragmentActivity.onMenuItemSelected(FragmentActivity.java:403)
at android.support.v7.app.AppCompatActivity.onMenuItemSelected(AppCompatActivity.java:189)
at android.support.v7.view.WindowCallbackWrapper.onMenuItemSelected(WindowCallbackWrapper.java:100)
at android.support.v7.app.AppCompatDelegateImplV7.onMenuItemSelected(AppCompatDelegateImplV7.java:663)
at android.support.v7.view.menu.MenuBuilder.dispatchMenuItemSelected(MenuBuilder.java:811)
at android.support.v7.view.menu.MenuItemImpl.invoke(MenuItemImpl.java:152)
at android.support.v7.view.menu.MenuBuilder.performItemAction(MenuBuilder.java:958)
at android.support.v7.view.menu.MenuBuilder.performItemAction(MenuBuilder.java:948)
at android.support.v7.view.menu.MenuPopupHelper.onItemClick(MenuPopupHelper.java:191)
at android.widget.AdapterView.performItemClick(AdapterView.java:305)
at android.widget.AbsListView.performItemClick(AbsListView.java:1146)
at android.widget.AbsListView$PerformClick.run(AbsListView.java:3053)
at android.widget.AbsListView$3.run(AbsListView.java:3860)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5254)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)
Can anyone tell me how to fix this. The image is loaded successfully and it still gives a NullPointerException.

I think you've not initialized the Mat trainGray. Try the following.
Mat trainGray = new Mat();
Imgproc.cvtColor(trainImage, trainGray, Imgproc.COLOR_RGBA2GRAY);

how to solve setOnCameraChangeListener Error method in google map [duplicate]

This question already has answers here:
What is a NullPointerException, and how do I fix it?
(12 answers)
Closed 6 years ago.
i'm implementing google maps in an android project . But as soon as i moved my project into another PC machine i'm facing app crashs and this error message in my logcat console :
FATAL EXCEPTION: main
Process: com.egsdigital.dolan, PID: 24887
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.egsdigital.dolan/com.egsdigital.dolan.Activities.MainPage_Pasenger}: java.lang.NullPointerException: Attempt to invoke virtual method 'void com.google.android.gms.maps.GoogleMap.setOnCameraChangeListener(com.google.android.gms.maps.GoogleMap$OnCameraChangeListener)' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2416)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476)
at android.app.ActivityThread.-wrap11(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5417)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void com.google.android.gms.maps.GoogleMap.setOnCameraChangeListener(com.google.android.gms.maps.GoogleMap$OnCameraChangeListener)' on a null object reference
at com.egsdigital.dolan.Activities.MainPage_Pasenger.onCreate(MainPage_Pasenger.java:178)
at android.app.Activity.performCreate(Activity.java:6237)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1107)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2369)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476) 
at android.app.ActivityThread.-wrap11(ActivityThread.java) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344) 
at android.os.Handler.dispatchMessage(Handler.java:102) 
at android.os.Looper.loop(Looper.java:148) 
at android.app.ActivityThread.main(ActivityThread.java:5417) 
at java.lang.reflect.Method.invoke(Native Method)
and here where the error points on:
map.setOnCameraChangeListener(new GoogleMap.OnCameraChangeListener() {
#Override
public void onCameraChange(CameraPosition position) {
LatLngBounds bounds = map.getProjection().getVisibleRegion().latLngBounds;
mAdapter.setBounds(bounds);
}
});
thanks so much.

you must add new SHA1 into google console.
See this link for fetch SHA1 from your OS : How to get the SHA1 fingerprint certificate in android studio for debug mode
After fetching your SHA1 code, insert into console.developers and running Application .
Hope help you

Why do i get a NullPointerException when I have checked for the the String not being null?

My app crashes on a NPE even though i'm checking whether the value of the String is non null:
if (AppConstants.AppConstants_appName != null &&
AppConstants.AppConstants_appName.equals("xxx")) {
suffix = "version=1.0";
}
AppConstants_appName is a public static String.
Not sure what's going wrong here.
Here's my Stacktrace. Anyone an idea?
Stacktrace
java.lang.NullPointerException: Attempt to invoke virtual method 'boolean java.lang.String.equals(java.lang.Object)' on a null object reference
at nl.onlineretailservice.library.APIManager.getURLSuffix(APIManager.java:637)
at nl.onlineretailservice.library.APIManager.requestFolderProducts(APIManager.java:334)
at nl.onlineretailservice.helper.FolderViewerActivityHelper.loadProducts(FolderViewerActivityHelper.java:160)
at nl.onlineretailservice.helper.FolderViewerActivityHelper$2.downloadReady(FolderViewerActivityHelper.java:267)
at nl.onlineretailservice.library.DownloadOperation.onPostExecute(DownloadOperation.java:221)
at android.os.AsyncTask.finish(AsyncTask.java:632)
at android.os.AsyncTask.access$600(AsyncTask.java:177)
at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:645)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:145)
at android.app.ActivityThread.main(ActivityThread.java:5832)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1399)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1194)