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androidsqliteonupdate

How to replace(overwrite) DB from external file


I want to replace old base to an new one from specific path. Should i remove old version an just copy new file? It works but app apply new base just after i clear cash or reboot device. Why so? Or i should use dbHelper.onUpgrade()? Probably its better. But i cant set arguments to onUpgrade() because it requires SQLiteDatabase as param, i have file path to db so how i can set necessary argument? It should look something like this:

    downloadDbPath = file.getPath();
    sql = new SQLiteDatabase().getPath(downloadDbPath);
    dbHelper.onUpgrade(sql, 1, 2);

and i have an error for second line Error: SQLiteDatabase() is not public in SQLiteDatabase; cannot be accessed from outside package So i cant create a new Object


Solution

  • Okay, if it interesting to somebody i did next: main method:

      public void downloadDb() {
            new FileChooser(this).setFileListener(new FileChooser.FileSelectedListener() {
                @Override public void fileSelected(final File file) {
                    downloadDbPath = file.getPath();
                    try {
                        InputStream in = new FileInputStream(downloadDbPath);
                        OutputStream out = new FileOutputStream(uploadDbPath);
    
                        // Transfer bytes from in to out
                        byte[] buf = new byte[1024];
                        int len;
                        while ((len = in.read(buf)) > 0) {
                            out.write(buf, 0, len);
                        }
                        deleteCache(context);
                        restartApp();
                        in.close();
                        out.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
            }).showDialog();
        }
    

    accessory:

    Clean Cache: https://stackoverflow.com/a/23908638/4540861

    <uses-permission android:name="android.permission.CLEAR_APP_CACHE"/>

    public static void deleteCache(Context context) {
        try {
            File dir = context.getCacheDir();
            deleteDir(dir);
        } catch (Exception e) {}
    }
    
    public static boolean deleteDir(File dir) {
        if (dir != null && dir.isDirectory()) {
            String[] children = dir.list();
            for (int i = 0; i < children.length; i++) {
                boolean success = deleteDir(new File(dir, children[i]));
                if (!success) {
                    return false;
                }
            }
            return dir.delete();
        } else if(dir!= null && dir.isFile()) {
            return dir.delete();
        } else {
            return false;
        }
    }
    

    Restart app: https://stackoverflow.com/a/17166729/4540861

    public void restartApp(){
        Intent mStartActivity = new Intent(context, MainActivity.class);
        int mPendingIntentId = 123456;
        PendingIntent mPendingIntent = PendingIntent.getActivity(context, mPendingIntentId,    mStartActivity, PendingIntent.FLAG_CANCEL_CURRENT);
        AlarmManager mgr = (AlarmManager)context.getSystemService(Context.ALARM_SERVICE);
        mgr.set(AlarmManager.RTC, System.currentTimeMillis() + 100, mPendingIntent);
        System.exit(0);
    }
    

    FileChooser: https://rogerkeays.com/simple-android-file-chooser

    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

    class FileChooser {
        private static final String PARENT_DIR = "..";
    
        private final Activity activity;
        private ListView list;
        private Dialog dialog;
        private File currentPath;
    
        // filter on file extension
        private String extension = null;
        public void setExtension(String extension) {
            this.extension = (extension == null) ? null :
                    extension.toLowerCase();
        }
    
        // file selection event handling
        public interface FileSelectedListener {
            void fileSelected(File file);
        }
    
        public FileChooser setFileListener(FileSelectedListener fileListener) {
            this.fileListener = fileListener;
            return this;
        }
    
        private FileSelectedListener fileListener;
    
        public FileChooser(Activity activity) {
            this.activity = activity;
            dialog = new Dialog(activity);
            list = new ListView(activity);
            list.setOnItemClickListener(new AdapterView.OnItemClickListener() {
                @Override public void onItemClick(AdapterView<?> parent, View view, int which, long id) {
                    String fileChosen = (String) list.getItemAtPosition(which);
                    File chosenFile = getChosenFile(fileChosen);
                    if (chosenFile.isDirectory()) {
                        refresh(chosenFile);
                    } else {
                        if (fileListener != null) {
                            fileListener.fileSelected(chosenFile);
                        }
                        dialog.dismiss();
                    }
                }
            });
            dialog.setContentView(list);
            dialog.getWindow().setLayout(LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT);
            refresh(Environment.getExternalStorageDirectory());
        }
    
        public void showDialog() {
            dialog.show();
        }
    
    
        /**
         * Sort, filter and display the files for the given path.
         */
        private void refresh(File path) {
            this.currentPath = path;
            if (path.exists()) {
                File[] dirs = path.listFiles(new FileFilter() {
                    @Override public boolean accept(File file) {
                        return (file.isDirectory() && file.canRead());
                    }
                });
                File[] files = path.listFiles(new FileFilter() {
                    @Override public boolean accept(File file) {
                        if (!file.isDirectory()) {
                            if (!file.canRead()) {
                                return false;
                            } else if (extension == null) {
                                return true;
                            } else {
                                return file.getName().toLowerCase().endsWith(extension);
                            }
                        } else {
                            return false;
                        }
                    }
                });
    
                // convert to an array
                int i = 0;
                String[] fileList;
                if (path.getParentFile() == null) {
                    fileList = new String[dirs.length + files.length];
                } else {
                    fileList = new String[dirs.length + files.length + 1];
                    fileList[i++] = PARENT_DIR;
                }
                Arrays.sort(dirs);
                Arrays.sort(files);
                for (File dir : dirs) { fileList[i++] = dir.getName(); }
                for (File file : files ) { fileList[i++] = file.getName(); }
    
                // refresh the user interface
                dialog.setTitle(currentPath.getPath());
                list.setAdapter(new ArrayAdapter(activity,
                        android.R.layout.simple_list_item_1, fileList) {
                    @Override public View getView(int pos, View view, ViewGroup parent) {
                        view = super.getView(pos, view, parent);
                        ((TextView) view).setSingleLine(true);
                        return view;
                    }
                });
            }
        }
    
    
        /**
         * Convert a relative filename into an actual File object.
         */
        private File getChosenFile(String fileChosen) {
            if (fileChosen.equals(PARENT_DIR)) {
                return currentPath.getParentFile();
            } else {
                return new File(currentPath, fileChosen);
            }
        }
    }