How to handle android.view.windowleaked error

Issue

I am adding images to the firebase storage. But before adding i want to check the network connectivity for that i used a AsyncTask. But after adding it my app started crashing...

Following is my AddImages.java File of fragment_add_images.xml file

package com.example.lenovo.jdstudio;
import android.app.ProgressDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.net.Uri;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.v4.app.Fragment;
import android.support.v7.app.AlertDialog;
import android.text.TextUtils;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.Spinner;
import android.widget.Toast;
import com.google.android.gms.tasks.OnFailureListener;
import com.google.android.gms.tasks.OnSuccessListener;
import com.google.firebase.storage.FirebaseStorage;
import com.google.firebase.storage.StorageReference;
import com.google.firebase.storage.UploadTask;
import java.io.IOException;
import java.net.HttpURLConnection;
import java.net.URL;
import static android.app.Activity.RESULT_OK;
import static android.content.ContentValues.TAG;
import static java.security.AccessController.getContext;

/**
 * A simple {@link Fragment} subclass.
 */
public class AddImages extends Fragment {
    private static final int GALLERY_REQUEST = 1;
    ArrayAdapter<CharSequence> adapter;
    private EditText mtitle;
    private EditText mresolution;
    private EditText mImageType;
    private EditText mprice;
    private Spinner mcategory;
    private ImageView mSelectImage;
    private Button mSbtn;
    private ProgressDialog mProgress;
    private Uri mImageuri = null;
    private StorageReference mStorage;

    public AddImages() {
        // Required empty public constructor
    }

    // checks if connection has active_internet connection
    public static boolean hasInternetAccess(Context context) {
        if (isNetworkAvailable(context)) {
            try {
                HttpURLConnection urlc = (HttpURLConnection)
                        (new URL("http://clients3.google.com/generate_204")
                                .openConnection());
                urlc.setRequestProperty("User-Agent", "Android");
                urlc.setRequestProperty("Connection", "close");
                urlc.setConnectTimeout(1500);
                urlc.connect();
                return (urlc.getResponseCode() == 204 &&
                        urlc.getContentLength() == 0);
            } catch (IOException e) {
                Log.e(TAG, "Error checking internet connection", e);
            }
        } else {
            return true;
        }
        return false;
    }

    // checks if user is connected to the any network
    private static boolean isNetworkAvailable(Context context) {
        ConnectivityManager connectivityManager
                = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo activeNetworkInfo = connectivityManager.getActiveNetworkInfo();
        return activeNetworkInfo != null;
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        View v = inflater.inflate(R.layout.fragment_add_images, container, false);
        mtitle = (EditText) v.findViewById(R.id.edit_title);
        mresolution = (EditText) v.findViewById(R.id.edit_resol);
        mSelectImage = (ImageView) v.findViewById(R.id.imageView);
        mImageType = (EditText) v.findViewById(R.id.edit_image_type);
        mprice = (EditText) v.findViewById(R.id.edit_price);
        mcategory = (Spinner) v.findViewById(R.id.cat_spin);
        mSbtn = (Button) v.findViewById(R.id.submit_btn);

        //Initialisee progress dialog
        mProgress = new ProgressDialog(getContext());
        mProgress.setIndeterminate(true);
        mProgress.setMessage("Uploading Please Wait...");

        // DB instance
        mStorage = FirebaseStorage.getInstance().getReference();

        //setting the spinner
        adapter = ArrayAdapter.createFromResource(getContext(), R.array.category, android.R.layout.simple_spinner_item);
        adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        mcategory.setAdapter(adapter);
        final String category_value = mcategory.getSelectedItem().toString();

        //Image Selection from gallery
        mSelectImage.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Intent galleryIntent = new Intent(Intent.ACTION_GET_CONTENT);
                galleryIntent.setType("image/*");
                startActivityForResult(galleryIntent, GALLERY_REQUEST);
            }
        });


        //Posting the activity on the database
        mSbtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {

                new UploadingTask().execute(category_value);

            }
        });
        return v;
    }

    // Start adding the images to the DB
    private void startAdding(String category_value) {


        StorageReference filepath = mStorage.child("My_Images").child(category_value).child(mImageuri.getLastPathSegment());
        filepath.putFile(mImageuri).addOnSuccessListener(new OnSuccessListener<UploadTask.TaskSnapshot>() {
            @Override
            public void onSuccess(UploadTask.TaskSnapshot taskSnapshot) {
                Uri downloadurl = taskSnapshot.getDownloadUrl();
            }
        }).addOnFailureListener(new OnFailureListener() {
            @Override
            public void onFailure(@NonNull Exception e) {
                mProgress.setMessage(e.getMessage());
                mProgress.show();
            }
        });
    }

    //show Alert box
    private void showAlert(String title, String message) {
        AlertDialog.Builder builder = new AlertDialog.Builder(getContext());
        builder.setTitle(title);
        builder.setMessage(message);
        builder.setNeutralButton("Dismiss", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                dialog.dismiss();
            }
        });
        builder.show();
    }

    //To show the progress dialog
    private void showProgressDialog(boolean shouldShow) {
        if (shouldShow) {
            mProgress.show();
        } else {
            mProgress.dismiss();
        }
    }

    // checks if user has entered all the field
    @NonNull
    private Boolean isFormValid() {
        String title_val = mtitle.getText().toString().trim();
        String resolution_val = mresolution.getText().toString().trim();
        String image_type_val = mImageType.getText().toString().trim();
        String price_val = mprice.getText().toString().trim();
        String category_value = mcategory.getSelectedItem().toString();

        if (!TextUtils.isEmpty(title_val) &&
                !TextUtils.isEmpty(resolution_val) &&
                !TextUtils.isEmpty(image_type_val) &&
                !TextUtils.isEmpty(price_val) &&
                mImageuri != null &&
                category_value != "Select Category") {
            return true;
        }
        return false;

    }

    //Reset  All the  value after uploading  the images
    private void clearAll() {
        mtitle.setText("");
        mresolution.setText("");
        mprice.setText("");
        mImageType.setText("");
        mcategory.setSelection(0);
        mSelectImage.setImageResource(R.mipmap.add_btn);
    }

    // Set the selected image from the gallery to the Imageview
    @Override
    public void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        if (requestCode == GALLERY_REQUEST && resultCode == RESULT_OK) {
            mImageuri = data.getData();

            mSelectImage.setImageURI(mImageuri);
        }
    }

    // perform all the task on the background Thread
    class UploadingTask extends AsyncTask<String, Void, Boolean> {
        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            if (isFormValid()) {
                showProgressDialog(true);
            } else {
                showAlert("Error", "Please fill all the details");
            }
        }

        @Override
        protected void onPostExecute(Boolean aBoolean) {
            super.onPostExecute(aBoolean);
            showProgressDialog(false);
            if (aBoolean) {
                showAlert("Successful", "Upload complete.");
            } else {
                showAlert("Failed", "Upload doesn't complete");
            }
            clearAll();

        }

        @Override
        protected Boolean doInBackground(String... params) {

            String catValue = params[0];
            if (hasInternetAccess(getContext())) {
                showAlert("Error", "Network is not available");
            } else {
                startAdding(catValue);
            }
            return null;
        }
    }
}

Following is the Error I am getting

E/WindowManager: android.view.WindowLeaked: Activity com.example.lenovo.jdstudio.MainActivity has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView{42192078 V.E..... R....... 0,0-683,378} that was originally added here
                     at android.view.ViewRootImpl.<init>(ViewRootImpl.java:422)
                     at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:250)
                     at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:69)
                     at android.app.Dialog.show(Dialog.java:297)
                     at android.support.v7.app.AlertDialog$Builder.show(AlertDialog.java:958)
                     at com.example.lenovo.jdstudio.AddImages.showAlert(AddImages.java:173)
                     at com.example.lenovo.jdstudio.AddImages.access$300(AddImages.java:45)
                     at com.example.lenovo.jdstudio.AddImages$UploadingTask.onPreExecute(AddImages.java:236)
                     at android.os.AsyncTask.executeOnExecutor(AsyncTask.java:587)
                     at android.os.AsyncTask.execute(AsyncTask.java:535)
                     at com.example.lenovo.jdstudio.AddImages$2.onClick(AddImages.java:136)
                     at android.view.View.performClick(View.java:4463)
                     at android.view.View$PerformClick.run(View.java:18770)
                     at android.os.Handler.handleCallback(Handler.java:808)
                     at android.os.Handler.dispatchMessage(Handler.java:103)
                     at android.os.Looper.loop(Looper.java:193)
                     at android.app.ActivityThread.main(ActivityThread.java:5333)
                     at java.lang.reflect.Method.invokeNative(Native Method)
                     at java.lang.reflect.Method.invoke(Method.java:515)
                     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:828)
                     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:644)
                     at dalvik.system.NativeStart.main(Native Method)
D/GraphicBuffer: create handle(0x6178f580) (w:688, h:378, f:1)
D/OpenGLRenderer: Flushing caches (mode 0)
D/GraphicBuffer: close handle(0x6177a680) (w:688 h:378 f:1)
D/GraphicBuffer: close handle(0x63688d98) (w:688 h:378 f:1)
D/GraphicBuffer: close handle(0x6178f580) (w:688 h:378 f:1)
D/ActivityThread: ACT-DESTROY_ACTIVITY handled : 1 / android.os.BinderProxy@42190ad0
V/FA: Connection attempt already in progress
D/FA: Connected to remote service
V/FA: Processing queued up service tasks: 2
D/SQLiteDatabase: beginTransaction()
D/SQLiteDatabase: endTransaction()
V/FA: Inactivity, disconnecting from the service
I/Process: Sending signal. PID: 10017 SIG: 9
W/IInputConnectionWrapper: showStatusIcon on inactive InputConnection
Disconnected from the target VM, address: 'localhost:8600', transport: 'socket'

Please Help me out!!

Solution

This is a problem I came across when attempting to show a ProgressDialog in onPreExecute() in an AsyncTask. The only solution I found was to manage the dialog outside the task, so instead of

mSbtn.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {

            new UploadingTask().execute(category_value);

        }
    });

try instead:

mSbtn.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            if (isFormValid()) {
               showProgressDialog(true);
               new UploadingTask().execute(category_value);
            } else {
               showAlert("Error", "Please fill all the details");
            }


        }
    });

And remove the corresponding code from the onPreExecute() method in UploadingTask.

I think the dialog can be dismissed in onPostExecute() without problem, but you could set up a callback interface to the task to notify the caller when the task is complete to allow it to manage the dismissal.

Answered By - AGDownie