App upgrade process now broken

[Oscar Blank]

I made an Activity that first checks the installed version of the app, checks what the newest version of the app is by doing an HTTP request to a webserver, and offers an upgrade if a newer version is available. When the "upgrade" button is clicked, it used to download the file, then initiate the installation process, but it's not initiating the installation of the apk anymore.

Another thing is that I used to have an older Android phone, and recently got a new phone. The new phone has Android 7.0 on it. That could be the reason, but I don't know.

If anyone can help I'd appreciate it.

package android.skoolkid.example;

import android.Manifest;
import android.app.DownloadManager;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.content.pm.PackageManager;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v4.util.ArrayMap;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;

import org.json.JSONObject;

import java.io.File;
import java.util.Map;

import static android.skoolkid.example.R.id.accessCode;

public class AppUpdateActivity extends AppCompatActivity implements HttpResponseListener {

    private String versionCheckUrl = "https://example.com/skool/app_version_check";
    private String upgradeFileUrl = "https://example.com/skool/download_apk";
    private String currentVersion;
    private Database db = new Database(this);
    Map<String, String> settings;
    public static final int MY_PERMISSIONS_REQUEST_WRITE_EXTERNAL_STORAGE = 9306;
    private long downloadId = 0;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_app_update);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        // Get current access code
        db.getReadableConnection();
        settings = db.getAppSettings();
        db.close();

        // Show current app version at bottom of screen
        TextView textView = (TextView) findViewById(R.id.version_num);
        String version = Integer.toString(android.skoolkid.example.BuildConfig.VERSION_CODE);
        String displayedVersion = "v" + version;
        textView.setText(displayedVersion);

        // Prep for HTTP request
        PostRequest request = new PostRequest();
        request.attachListener(AppUpdateActivity.this);
        // Build up the post variables
        ArrayMap<String, String> postVars = new ArrayMap<>();
        postVars.put("access_code", settings.get("accessCode"));
        postVars.put("version", version);
        // Pass the post variables to the handler
        request.setPostVars(postVars);
        // Send request
        request.send(versionCheckUrl);

        // Set OnClickListener for submit button
        findViewById(R.id.upgradeAppButton).setOnClickListener(upgradeButton_OnClickListener);
    }

    final View.OnClickListener upgradeButton_OnClickListener = new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            /**
             * Due to Android requiring permission to download files, we must ask
             * the user for the permission, and handle their response.
             */
            if (ContextCompat.checkSelfPermission(AppUpdateActivity.this,
                    Manifest.permission.WRITE_EXTERNAL_STORAGE)
                    != PackageManager.PERMISSION_GRANTED) {
                // Should we show an explanation?
                if (ActivityCompat.shouldShowRequestPermissionRationale(AppUpdateActivity.this,
                        Manifest.permission.WRITE_EXTERNAL_STORAGE)) {
                    // Show an expanation to the user *asynchronously*
                    Context context = getApplicationContext();
                    CharSequence text = "Your permission to write to external storage is necessary" +
                            "because Android will not allow us to download the update file without it.";
                    Toast toast = Toast.makeText(context, text, Toast.LENGTH_SHORT);
                    toast.show();
                } else {
                    // No explanation needed, we can request the permission.
                    ActivityCompat.requestPermissions(AppUpdateActivity.this,
                            new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},
                            MY_PERMISSIONS_REQUEST_WRITE_EXTERNAL_STORAGE);
                }
            }else{
                doUpgradeDownload();
            }
        }
    };

    @Override
    public void onRequestPermissionsResult(int requestCode, String permissions[], int[] grantResults) {
        switch (requestCode) {
            case MY_PERMISSIONS_REQUEST_WRITE_EXTERNAL_STORAGE: {
                // If request is cancelled, the result arrays are empty.
                if (grantResults.length > 0
                        && grantResults[0] == PackageManager.PERMISSION_GRANTED) {

                    // Permission was granted
                    doUpgradeDownload();
                }
            }
        }
    }

    public void doUpgradeDownload(){
        // Download the APK file from the web server
        Uri uri = Uri.parse(upgradeFileUrl + "/" + currentVersion);
        DownloadManager.Request request = new DownloadManager.Request(uri);
        request.setTitle("Example App v" + currentVersion);
        request.setDescription("Example Android App Update v" + currentVersion);
        request.setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED);
        request.setDestinationInExternalPublicDir(Environment.DIRECTORY_DOWNLOADS, "exampleApp" + currentVersion + ".apk" );
        request.setMimeType("application/vnd.android.package-archive");
        DownloadManager manager = (DownloadManager) AppUpdateActivity.this.getSystemService(Context.DOWNLOAD_SERVICE);
        // Listen for when the download is done
        registerReceiver(onDownloadComplete, new IntentFilter(DownloadManager.ACTION_DOWNLOAD_COMPLETE));
        downloadId = manager.enqueue(request);
    }

    BroadcastReceiver onDownloadComplete = new BroadcastReceiver(){
        @Override
        public void onReceive(Context context, Intent intent) {
            /**
             * When the download is done, we verify that the downloaded file has an ID
             * that matches the one we were expecting, then make sure it was successful,
             * and finally use it with intent to install.
             */
            try {
                Bundle extras = intent.getExtras();
                long downloadCompletedId = extras.getLong(DownloadManager.EXTRA_DOWNLOAD_ID);
                DownloadManager.Query q = new DownloadManager.Query();
                // Verify the ID
                if (downloadId == downloadCompletedId) {
                    q.setFilterById(downloadCompletedId);
                    DownloadManager mManager = (DownloadManager) AppUpdateActivity.this.getSystemService(Context.DOWNLOAD_SERVICE);
                    Cursor c = mManager.query(q);
                    if (c.moveToFirst()) {
                        int status = c.getInt(c.getColumnIndex(DownloadManager.COLUMN_STATUS));
                        // Make sure status was successful
                        if (status == DownloadManager.STATUS_SUCCESSFUL) {
                            Intent promptInstall = new Intent(Intent.ACTION_VIEW);
                            promptInstall.setDataAndType(
                                    Uri.fromFile(new File(Environment.getExternalStorageDirectory() + "/download/exampleApp" + currentVersion + ".apk")),
                                    "application/vnd.android.package-archive");
                            promptInstall.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                            // Use it for installation of update
                            startActivity(promptInstall);
                        }
                    }
                    c.close();
                }
            }catch(Exception e){}
        }
    };

    @Override
    public void handleResponseData(String msg, String s) {
        try{
            // Transform the json into a real json object
            JSONObject jsnobject = new JSONObject(s);
            // A response with status = 1 means there is a new version
            if( jsnobject.has("status") && jsnobject.getString("status").equals("1") && jsnobject.has("version") ){
                // Set the current version
                currentVersion = jsnobject.getString("version");
                // Show upgrade button at bottom of view
                Button upgradeButton = (Button) findViewById(R.id.upgradeAppButton);
                upgradeButton.setVisibility(View.VISIBLE);
            }
        } catch (Exception e) {}
    }

    @Override
    protected void onDestroy(){
        super.onDestroy();
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main_only_showing_home, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        int id = item.getItemId();
        if (id == R.id.action_home) {
            // Home
            finish();
        }
        return super.onOptionsItemSelected(item);
    }
}

[Oscar Blank]

So, I may have found the solution, and it has to to with Android N changing what's allowed to be done with files:

In AndroidManifest.xml

<provider
            android:name="android.support.v4.content.FileProvider"
            android:authorities="${applicationId}.provider"
            android:exported="false"
            android:grantUriPermissions="true">
            <meta-data
                android:name="android.support.FILE_PROVIDER_PATHS"
                android:resource="@xml/provider_paths"/>
</provider>

Create file in res/xml/provider_paths.xml

<?xml version="1.0" encoding="utf-8"?>
<paths xmlns:android="http://schemas.android.com/apk/res/android">
    <external-path name="external_files" path="."/>
</paths>

And the contents of the BroadcastReceiver changes

BroadcastReceiver onDownloadComplete = new BroadcastReceiver(){
    @Override
    public void onReceive(Context context, Intent intent) {
        /**
         * When the download is done, we verify that the downloaded file has an ID
         * that matches the one we were expecting, then make sure it was successful,
         * and finally use it with intent to install.
         */
        try {
            Bundle extras = intent.getExtras();
            long downloadCompletedId = extras.getLong(DownloadManager.EXTRA_DOWNLOAD_ID);
            DownloadManager.Query q = new DownloadManager.Query();
            if (downloadId == downloadCompletedId) {
                q.setFilterById(downloadCompletedId);
                DownloadManager mManager = (DownloadManager) AppUpdateActivity.this.getSystemService(Context.DOWNLOAD_SERVICE);
                Cursor c = mManager.query(q);
                if (c.moveToFirst()) {
                    int status = c.getInt(c.getColumnIndex(DownloadManager.COLUMN_STATUS));
                    if (status == DownloadManager.STATUS_SUCCESSFUL) {
                        String mediaType = c.getString(c.getColumnIndex(DownloadManager.COLUMN_MEDIA_TYPE));
                        int columnIndex = c.getColumnIndex(DownloadManager.COLUMN_LOCAL_URI);
                        String downloadFileLocalUri = c.getString(columnIndex);
                        if (downloadFileLocalUri != null){
                            if (downloadFileLocalUri.substring(0, 7).matches("file://")) {
                                downloadFileLocalUri =  downloadFileLocalUri.substring(7);
                            }
                            File mFile = new File(downloadFileLocalUri);
                            Uri apkURI = FileProvider.getUriForFile(context, context.getApplicationContext().getPackageName() + ".provider", mFile);
                            Intent promptInstall = new Intent(Intent.ACTION_VIEW);
                            promptInstall.setDataAndType(
                                    apkURI,
                                    mediaType);
                            promptInstall.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                            startActivity(promptInstall);
                        }
                    }
                }
                c.close();
            }
        }catch(Exception e){
            Log.d("dEBorG", e.getMessage());
        }
    }
};

Thing is, I don't really know what I'm doing here, and being that I have a lot of non-Android experience, I'm wondering there are some problems with this.

[Oscar Blank]

And more changes to the broadcast receiver once I realized that there needed to be two different ways of completing the task based on the version of Android:

BroadcastReceiver onDownloadComplete = new BroadcastReceiver(){
    @Override
    public void onReceive(Context context, Intent intent) {
        try {
            Bundle extras = intent.getExtras();
            long downloadCompletedId = extras.getLong(DownloadManager.EXTRA_DOWNLOAD_ID);
            DownloadManager.Query q = new DownloadManager.Query();
            // Verify the IDs match
            if (downloadId == downloadCompletedId) {
                q.setFilterById(downloadCompletedId);
                DownloadManager mManager = (DownloadManager) AppUpdateActivity.this.getSystemService(Context.DOWNLOAD_SERVICE);
                Cursor c = mManager.query(q);
                if (c.moveToFirst()) {
                    int columnStatus = c.getInt(c.getColumnIndex(DownloadManager.COLUMN_STATUS));
                    String downloadFileLocalUri = c.getString(c.getColumnIndex(DownloadManager.COLUMN_LOCAL_URI));
                    String MediaType = c.getString(c.getColumnIndex(DownloadManager.COLUMN_MEDIA_TYPE));
                    // Make sure download status was successful
                    if (columnStatus == DownloadManager.STATUS_SUCCESSFUL) {
                        // Make sure we actually have a downloaded file URI
                        if (downloadFileLocalUri != null){
                            // Strip off file://
                            if (downloadFileLocalUri.substring(0, 7).matches("file://")) {
                                downloadFileLocalUri = downloadFileLocalUri.substring(7);
                            }

                            File mFile = new File(downloadFileLocalUri);
  
                            if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.N){
                                // Android N+ uses content provider (FileProvider)
                                Uri apkURI = FileProvider.getUriForFile(
                                        context, context.getApplicationContext().getPackageName() + ".provider", mFile);
                                Intent promptInstall = new Intent(Intent.ACTION_INSTALL_PACKAGE);
                                promptInstall.setDataAndType(apkURI, MediaType);
                                promptInstall.setFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
                                startActivity(promptInstall);
                            }else {
                                // Android older than N
                                Uri apkURI = Uri.fromFile(mFile);
                                Intent promptInstall = new Intent(Intent.ACTION_VIEW);
                                promptInstall.setDataAndType(apkURI, MediaType);
                                promptInstall.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                                startActivity(promptInstall);
                            }
                        }
                    }
                }
                c.close();
            }
        }catch(Exception e){
            Log.d("dEBorG", e.getMessage());
        }
    }
};