Develop Reference

On clicking predict button, the app crashes

Recently I have been working on android studio, I built a python image classification model and want to integrate it with an app. But when I click on predict button, the app crashes. Would be helpful if I can get the idea as to where things are going wrong.
Attached is the code and the error it throws -
Activitymain.java :-
package com.example.uni;
import android.content.Intent;
import android.graphics.Bitmap;
import android.net.Uri;
import android.os.Bundle;
import android.provider.MediaStore;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;
import androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;
import com.example.uni.ml.ConvertedModel;
import org.tensorflow.lite.DataType;
import org.tensorflow.lite.support.image.TensorImage;
import org.tensorflow.lite.support.tensorbuffer.TensorBuffer;
import java.io.IOException;
import java.nio.ByteBuffer;
public class MainActivity extends AppCompatActivity {
private ImageView imgView;
private Button predict;
private Button select;
private TextView tv;
private Bitmap img;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
imgView = (ImageView) findViewById(R.id.imageView);
tv = (TextView) findViewById(R.id.textView);
select = (Button) findViewById(R.id.button);
predict = (Button) findViewById(R.id.button2);
select.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
intent.setType("image/*");
startActivityForResult(intent,12);
}
});
predict.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
img = Bitmap.createScaledBitmap(img,
500,
500,
true);
try {
ConvertedModel model = ConvertedModel.newInstance(getApplicationContext());
// Creates inputs for reference.
TensorBuffer inputFeature0 = TensorBuffer.createFixedSize(new int[]{1, 500, 500, 3}, DataType.FLOAT32);
TensorImage tensorImage = new TensorImage(DataType.FLOAT32);
tensorImage.load(img);
ByteBuffer byteBuffer = tensorImage.getBuffer();
inputFeature0.loadBuffer(byteBuffer);
// Runs model inference and gets result.
ConvertedModel.Outputs outputs = model.process(inputFeature0);
TensorBuffer outputFeature0 = outputs.getOutputFeature0AsTensorBuffer();
// Releases model resources if no longer used.
model.close();
tv.setText((int) outputFeature0.getFloatArray()[0]);
} catch (IOException e) {
/* TODO Handle the exception */
}
}
});
}
#Override
protected void onActivityResult(int requestCode, int resultCode, #Nullable Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if(requestCode == 100)
{
imgView.setImageURI(data.getData());
Uri uri = data.getData();
try {
img = MediaStore.Images.Media.getBitmap(this.getContentResolver(),uri);
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
In logcat I see this -
2021-11-05 13:23:38.040 24027-24027/com.example.uni I/tflite: Initialized TensorFlow Lite runtime.
2021-11-05 13:23:38.090 24027-24027/com.example.uni E/libc: Access denied finding property "ro.hardware.chipname"
2021-11-05 13:23:38.081 24027-24027/com.example.uni W/com.example.uni: type=1400 audit(0.0:232245): avc: denied { read } for name="u:object_r:vendor_default_prop:s0" dev="tmpfs" ino=14249 scontext=u:r:untrusted_app:s0:c48,c257,c512,c768 tcontext=u:object_r:vendor_default_prop:s0 tclass=file permissive=0
2021-11-05 13:23:38.841 24027-24027/com.example.uni E/com.example.un: Invalid ID 0x00000000.
2021-11-05 13:23:38.842 24027-24027/com.example.uni D/AndroidRuntime: Shutting down VM
2021-11-05 13:23:38.843 24027-24027/com.example.uni E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.uni, PID: 24027
android.content.res.Resources$NotFoundException: String resource ID #0x0
at android.content.res.Resources.getText(Resources.java:381)
at android.content.res.MiuiResources.getText(MiuiResources.java:97)
at android.widget.TextView.setText(TextView.java:6397)
at com.example.uni.MainActivity$2.onClick(MainActivity.java:85)
at android.view.View.performClick(View.java:7189)
at com.google.android.material.button.MaterialButton.performClick(MaterialButton.java:1119)
at android.view.View.performClickInternal(View.java:7166)
at android.view.View.access$3500(View.java:819)
at android.view.View$PerformClick.run(View.java:27682)
at android.os.Handler.handleCallback(Handler.java:883)
at android.os.Handler.dispatchMessage(Handler.java:100)
at android.os.Looper.loop(Looper.java:224)
at android.app.ActivityThread.main(ActivityThread.java:7592)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:539)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:950)
2021-11-05 13:23:38.887 24027-24027/com.example.uni I/Process: Sending signal. PID: 24027 SIG: 9
Need suggestions as to what's going on and how to resolve it. I'm using android studio arctic fox 2020.3.1 patch 3.

The logcat already told you that it crashed at the setText() call. You called
tv.setText((int) outputFeature0.getFloatArray()[0]);
The int in setText(int) refers to a Resource ID defined in the string.xml (R.string.xxx).
If you are not getting the string from res, you should use setText(CharSequence) instead.
You probably want
tv.setText(String.format("%f",outputFeature0.getFloatArray()[0]));
(change "%f" to any decimal points or format you want)

My app quits as soon as picture is selected

I have created an app that basically takes a picture and saves it to the gallery. The only problem is that after the picture is taken it takes you to the screen where you can preview it with the two buttons that say okay and cancel. Once you click okay, the app quits. The image is still saved to the gallery but I want the app to stay open. I also want the app to display a bitmap of the image on an imageView that I have.
Here is my MainActivity.java
package com.example.app;
import androidx.appcompat.app.AppCompatActivity;
import androidx.core.content.FileProvider;
import android.content.Intent;
import android.graphics.Bitmap;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.provider.MediaStore;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.Toast;
import java.io.File;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;
public class MainActivity extends AppCompatActivity { <- Line 22
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button btn = findViewById(R.id.button);
btn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
dispatchTakePictureIntent(); <- Line 34
}
});
}
static final int REQUEST_IMAGE_CAPTURE = 1;
private void dispatchTakePictureIntent() {
Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
// Ensure that there's a camera activity to handle the intent
if (takePictureIntent.resolveActivity(getPackageManager()) != null) {
// Create the File where the photo should go
File photoFile = null;
try {
photoFile = createImageFile();
} catch (IOException ex) {
// Error occurred while creating the File
// I AM UNSURE WHAT CODE TO PUT HERE. DOES ANYONE KNOW WHAT I SHOULD BE PUTTING HERE?
}
// Continue only if the File was successfully created
if (photoFile != null) {
//This is where the error is occurring but I do not know why.
Line 56 -> Uri photoURI = FileProvider.getUriForFile(this, "com.example.app", photoFile);
takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT, photoURI);
startActivityForResult(takePictureIntent, REQUEST_IMAGE_CAPTURE);
}
}
}
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == REQUEST_IMAGE_CAPTURE && resultCode == RESULT_OK) {
Bundle extras = data.getExtras();
Bitmap imageBitmap = (Bitmap) extras.get("data");
ImageView imageView = findViewById(R.id.imageView);
imageView.setImageBitmap(imageBitmap);
}
}
String currentPhotoPath;
private File createImageFile() throws IOException {
// Create an image file name
String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
String imageFileName = "JPEG_" + timeStamp + "_";
File storageDir = getExternalFilesDir(Environment.DIRECTORY_PICTURES);
File image = File.createTempFile(
imageFileName, /* prefix */
".jpg", /* suffix */
storageDir /* directory */
);
// Save a file: path for use with ACTION_VIEW intents
currentPhotoPath = image.getAbsolutePath();
return image;
}
private void galleryAddPic() {
Intent mediaScanIntent = new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE);
File f = new File(currentPhotoPath);
Uri contentUri = Uri.fromFile(f);
mediaScanIntent.setData(contentUri);
this.sendBroadcast(mediaScanIntent);
}
}
Here is my error message
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.app, PID: 22357
java.lang.IllegalArgumentException: Couldn't find meta-data for provider with authority com.example.app
at androidx.core.content.FileProvider.parsePathStrategy(FileProvider.java:606)
at androidx.core.content.FileProvider.getPathStrategy(FileProvider.java:579)
at androidx.core.content.FileProvider.getUriForFile(FileProvider.java:417)
--> at com.example.app.MainActivity.dispatchTakePictureIntent(MainActivity.java:56)
--> at com.example.app.MainActivity.access$000(MainActivity.java:22)
--> at com.example.app.MainActivity$1.onClick(MainActivity.java:34)
at android.view.View.performClick(View.java:7870)
at android.widget.TextView.performClick(TextView.java:14966)
at android.view.View.performClickInternal(View.java:7839)
at android.view.View.access$3600(View.java:886)
at android.view.View$PerformClick.run(View.java:29315)
at android.os.Handler.handleCallback(Handler.java:883)
at android.os.Handler.dispatchMessage(Handler.java:100)
at android.os.Looper.loop(Looper.java:237)
at android.app.ActivityThread.main(ActivityThread.java:7777)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1047)
I/Process: Sending signal. PID: 22357 SIG: 9

Attempt to invoke virtual method 'void android.widget.Button.setEnabled(boolean)' on a null object reference error

I'm new at coding and I am making simple flashlight android program in Android Studio. But I am getting this problem (shown in LogCat) and don't know how to resolve it.
I tried searching of this error in forums, tried debugging, but it didn't help. Any ideas?
The whole script
import android.Manifest;
import android.content.Context;
import android.content.pm.PackageManager;
import android.hardware.camera2.CameraAccessException;
import android.hardware.camera2.CameraManager;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.Toast;
public class FlashActivity extends AppCompatActivity {
private Button buttonEnable;
private ImageView imageFlashlight;
private static final int CAMERA_REQUEST = 50;
private boolean flashLightStatus = false;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
imageFlashlight = (ImageView) findViewById(R.id.imageFlashlight);
buttonEnable = (Button) findViewById(R.id.buttonEnable);
final boolean hasCameraFlash = getPackageManager().
hasSystemFeature(PackageManager.FEATURE_CAMERA_FLASH);
boolean isEnabled = ContextCompat.checkSelfPermission(this, Manifest.permission.CAMERA)
== PackageManager.PERMISSION_GRANTED;
buttonEnable.setEnabled(!isEnabled);
imageFlashlight.setEnabled(isEnabled);
buttonEnable.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
ActivityCompat.requestPermissions(FlashActivity.this, new String[] {Manifest.permission.CAMERA}, CAMERA_REQUEST);
}
});
imageFlashlight.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
if (hasCameraFlash) {
if (flashLightStatus)
flashLightOff();
else
flashLightOn();
} else {
Toast.makeText(FlashActivity.this, "No flash available on your device",
Toast.LENGTH_SHORT).show();
}
}
});
}
private void flashLightOn() {
CameraManager cameraManager = (CameraManager) getSystemService(Context.CAMERA_SERVICE);
try {
String cameraId = cameraManager.getCameraIdList()[0];
cameraManager.setTorchMode(cameraId, true);
flashLightStatus = true;
imageFlashlight.setImageResource(R.drawable.on);
} catch (CameraAccessException e) {
}
}
private void flashLightOff() {
CameraManager cameraManager = (CameraManager) getSystemService(Context.CAMERA_SERVICE);
try {
String cameraId = cameraManager.getCameraIdList()[0];
cameraManager.setTorchMode(cameraId, false);
flashLightStatus = false;
imageFlashlight.setImageResource(R.drawable.off);
} catch (CameraAccessException e) {
}
}
#Override
public void onRequestPermissionsResult(int requestCode, #NonNull String[] permissions, #NonNull int[] grantResults) {
switch(requestCode) {
case CAMERA_REQUEST :
if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
buttonEnable.setEnabled(false);
buttonEnable.setText("Camera Enabled");
imageFlashlight.setEnabled(true);
} else {
Toast.makeText(FlashActivity.this, "Permission Denied for the Camera", Toast.LENGTH_SHORT).show();
}
break;
}
}
}
The error of Log Cat
E/AndroidRuntime: FATAL EXCEPTION: main
Process: l.www.survivalbook, PID: 8117
java.lang.RuntimeException: Unable to start activity ComponentInfo{l.www.survivalbook/l.www.survivalbook.FlashActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.Button.setEnabled(boolean)' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2957)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3032)
at android.app.ActivityThread.-wrap11(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1696)
at android.os.Handler.dispatchMessage(Handler.java:105)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6944)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:327)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1374)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.Button.setEnabled(boolean)' on a null object reference
at l.www.survivalbook.FlashActivity.onCreate(FlashActivity.java:39)
at android.app.Activity.performCreate(Activity.java:7183)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1220)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2910)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3032) 
at android.app.ActivityThread.-wrap11(Unknown Source:0) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1696) 
at android.os.Handler.dispatchMessage(Handler.java:105) 
at android.os.Looper.loop(Looper.java:164) 
at android.app.ActivityThread.main(ActivityThread.java:6944) 
at java.lang.reflect.Method.invoke(Native Method) 
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:327) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1374) 
the line, where error is shown (39 code line)
buttonEnable.setEnabled(!isEnabled);
imageFlashlight.setEnabled(isEnabled);
Here is xml script
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/activity_compass"
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:textAlignment="center"
android:textSize="40sp"
android:textColor="#000"
android:textStyle="bold"
android:text="0°"
android:id="#+id/txt_azimuth"/>
<ImageView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:src="#drawable/kompasas"
android:layout_below="#+id/txt_azimuth"
android:id="#+id/img_compass"/>
</RelativeLayout>

A null object Reference always points out that there is some object in your code that has no value.
Button myButton = null;
myButton.setVisibility(GONE);
The code above will always lead to the error that appears in your code. Your buttonEnable has no value. Try buttonEnable = new Button() or use findViewById if you declared the button within your layout XML.

How can I redirect 2 buttons to different intents in android?

enter image description here
I put a listener on each button that takes me to different activities.
The login button works perfectly, but the register button stops the app when I click on it.
I've tried to put a Toast message in the _btnreg listener, and it worked...
I got this error:
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.android.virtualshelter, PID: 24128
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.android.virtualshelter/com.example.android.virtualshelter.register}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.Button.setOnClickListener(android.view.View$OnClickListener)' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2726)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2787)
at android.app.ActivityThread.-wrap12(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1504)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6247)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:872)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:762)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.Button.setOnClickListener(android.view.View$OnClickListener)' on a null object reference
at com.example.android.virtualshelter.register.onCreate(register.java:35)
at android.app.Activity.performCreate(Activity.java:6754)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1119)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2679)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2787) 
at android.app.ActivityThread.-wrap12(ActivityThread.java) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1504) 
at android.os.Handler.dispatchMessage(Handler.java:102) 
at android.os.Looper.loop(Looper.java:154) 
at android.app.ActivityThread.main(ActivityThread.java:6247) 
at java.lang.reflect.Method.invoke(Native Method) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:872) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:762) 
package com.example.android.virtualshelter;
import android.content.ContentValues;
import android.content.Intent;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.*;
public class MainActivity extends AppCompatActivity
{
Button _btnreg, _btnlogin;
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
_btnlogin = findViewById(R.id.btnlogin);
_btnreg = findViewById(R.id.btnreg);
_btnreg.setOnClickListener(new View.OnClickListener()
{
#Override
public void onClick(View v)
{
Intent intent = new Intent(MainActivity.this,register.class);
startActivity(intent);
}
});
_btnlogin.setOnClickListener(new View.OnClickListener()
{
#Override
public void onClick(View v)
{
Intent intent = new Intent(MainActivity.this,login.class);
startActivity(intent);
}
});
}
}
My register.java code
package com.example.android.virtualshelter;
import android.content.ContentValues;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
public class register extends AppCompatActivity
{
SQLiteOpenHelper openHelper;
SQLiteDatabase db;
Button _btnReg;
EditText _txtfname, _txtlname, _txtpass, _txtemail, _txtphone;
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_register);
openHelper = new DatabaseHelper(register.this);
_txtfname = findViewById(R.id.txtfname);
_txtlname = findViewById(R.id.txtlname);
_txtpass = findViewById(R.id.txtpass);
_txtemail = findViewById(R.id.txtemail);
_txtphone = findViewById(R.id.txtphone);
_btnReg = findViewById(R.id.btnreg);
_btnReg.setOnClickListener(new View.OnClickListener()
{
#Override
public void onClick(View v)
{
db = openHelper.getWritableDatabase();
String fname = _txtfname.getText().toString();
String lname = _txtlname.getText().toString();
String pass = _txtpass.getText().toString();
String email = _txtemail.getText().toString();
String phone = _txtphone.getText().toString();
insertdata(fname, lname, pass, email, phone);
Toast.makeText(getApplicationContext(), "register successfully", Toast.LENGTH_LONG).show();
}
});
}
public void insertdata(String fname, String lname, String pass, String email, String phone)
{
ContentValues contentValues = new ContentValues();
contentValues.put(DatabaseHelper.COL_2, fname);
contentValues.put(DatabaseHelper.COL_3, lname);
contentValues.put(DatabaseHelper.COL_4, pass);
contentValues.put(DatabaseHelper.COL_5, email);
contentValues.put(DatabaseHelper.COL_6, phone);
long id = db.insert(DatabaseHelper.TABLE_NAME, null, contentValues);
}
}
I expect to go to activity register.java, but the app is crashing

My hunch is, you are not able find the button, causing a NPE when setting the listner. Could be that you don't have the button defined in R.layout.activity_main, but in a different layout.

Android intent error null object reference [duplicate]

This question already has answers here:
What is a NullPointerException, and how do I fix it?
(12 answers)
Closed 6 years ago.
Hello im new in stackover flow i want to try these website and ask for someones help in my android when i change the intent there's an error in my android monitor in android studio here is it.
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.kim.checkerv3, PID: 2970
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.kim.checkerv3/com.example.kim.checkerv3.BudgetOutput}: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String android.os.BaseBundle.getString(java.lang.String)' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2646)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2707)
at android.app.ActivityThread.-wrap12(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1460)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6077)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:865)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:755)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String android.os.BaseBundle.getString(java.lang.String)' on a null object reference
at com.example.kim.checkerv3.BudgetOutput.onCreate(BudgetOutput.java:22)
at android.app.Activity.performCreate(Activity.java:6664)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2599)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2707) 
at android.app.ActivityThread.-wrap12(ActivityThread.java) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1460) 
at android.os.Handler.dispatchMessage(Handler.java:102) 
at android.os.Looper.loop(Looper.java:154) 
at android.app.ActivityThread.main(ActivityThread.java:6077) 
at java.lang.reflect.Method.invoke(Native Method) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:865) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:755) 
i didn't understand this i'd tried researching for solution and im still stuck on it.
Here the intent will be pass to other java class.
package com.example.kim.checkerv3;
import android.app.Fragment;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v7.app.AlertDialog;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.EditText;
import com.android.volley.RequestQueue;
import com.android.volley.Response;
import com.android.volley.toolbox.Volley;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import static android.content.Context.MODE_PRIVATE;
/**
* Created by KIM-PC on 12/5/2016.
*/
public class BudgetFragment extends android.support.v4.app.Fragment {
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.activity_budget, container, false);
final EditText etCash = (EditText) v.findViewById(R.id.etCash);
final Button bBudget = (Button) v.findViewById(R.id.bBudget);
bBudget.setOnClickListener(new View.OnClickListener(){
public void onClick(View v) {
SharedPreferences sharedpref = getContext().getSharedPreferences("user_id", MODE_PRIVATE);
String id = sharedpref.getString("user_id","");
final int budgeted = Integer.parseInt(etCash.getText().toString());
Response.Listener<String> responseListener = new Response.Listener<String>() {
#Override
public void onResponse(String response) {
try {
JSONObject jsonResponse = new JSONObject(response);
JSONArray arr = jsonResponse.getJSONArray("message");
boolean success = jsonResponse.getBoolean("success");
System.out.println(budgeted/arr.length());
int total = budgeted/arr.length();
if (success) {
Intent intent = new Intent(getContext(), BudgetOutput.class);
Bundle b = new Bundle();
b.putString("total", String.valueOf(total));
getContext().startActivity(intent);
if (arr != null) {
int sum = 0;
for(int i = 0;i<arr.length();i++){
//listdata.add(arr.get(i).toString());
String money = arr.getJSONObject(i).getString("amount");
sum += Integer.parseInt(money);
}
SharedPreferences sharedPref1 = getActivity().getSharedPreferences("mypref", Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPref1.edit();
editor.putInt("TotalSum", sum);
editor.commit();
System.out.println(sum);
//arrayAdapter.notifyDataSetChanged();
}
} else {
AlertDialog.Builder builder = new AlertDialog.Builder(getContext());
builder.setMessage("Failed to fetch. Try again.")
.setNegativeButton("OK", null)
.create()
.show();
}
} catch (JSONException e) {
e.printStackTrace();
}
}
};
RecordRequest recordRequest = new RecordRequest(id, responseListener);
RequestQueue queue = Volley.newRequestQueue(getContext());
queue.add(recordRequest);
}
});
return v;
}
#Override
public void onAttach(Context context) {
super.onAttach(context);
SharedPreferences sharedpref1 = getContext().getSharedPreferences("mypref", MODE_PRIVATE);
int budgeted = sharedpref1.getInt("TotalSum", 0);
System.out.println(budgeted/2);
}
}
and the class where the intent will be get.
package com.example.kim.checkerv3;
import android.content.Intent;
import android.os.Bundle;
import android.os.PersistableBundle;
import android.support.v7.app.AppCompatActivity;
import android.widget.EditText;
import android.widget.TextView;
/**
* Created by KIM-PC on 12/6/2016.
*/
public class BudgetOutput extends AppCompatActivity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_output);
final TextView tvOutput = (TextView) findViewById(R.id.tvoutput);
Bundle b = getIntent().getExtras();
String output=b.getString("total");
if(b !=null)
output = b.getString("total");
tvOutput.setText(output+" Per cheque record.");
}
}
if there is someone who could solve i appreciate and give my thanks to you.

Well, you forgot to add your Bundle to the Intent
Intent intent = new Intent(getContext(), BudgetOutput.class);
Bundle b = new Bundle();
b.putString("total", String.valueOf(total));
intent.putExtras(b);
getContext().startActivity(intent);