how to fetch data from local json file?

Question

I created a json file locally. I can view that in data>data>com.example.storage>files>filename.json. Using this, I want to fetch all the text values locally & download a

Answer 1

Well its quite simple! here it goes:

private void DoWork() {
    File file = new File(Environment.getExternalStorageDirectory().getAbsolutePath(),
            "file.json"); //path to your file assuming its in root of SD card

    String content = "";
    try {
        BufferedReader br = new BufferedReader(new FileReader(file));
        try {
            StringBuilder sb = new StringBuilder();
            String line = br.readLine();

            while (line != null) {
                sb.append(line);
                line = br.readLine();
            }
            content = sb.toString();
        } finally {
            br.close();
        }
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    } catch (IOException io) {
        io.printStackTrace();
    }

    mTextView.setText(""); // A multiline text view big enough
    mTextView.append("\n\n-----START CONTENT-----\n\n");
    mTextView.append(content);
    mTextView.append("\n\n-----START JSON-----\n\n");

    try {
        JSONArray jsonArray = new JSONArray(content);
        int length = jsonArray.length();

        for (int i = 0; i < length; i++) { /itterate throu json array
            JSONObject obj = jsonArray.getJSONObject(i);

             //here you can access individual parts of you json object by getString()...getBoolean().... etc...

            mTextView.append("\n" + obj.toString()); 
        }
    } catch (JSONException e) {
        e.printStackTrace();
    }
}

To read an internal file belonging to the app directory try:

  this.openFileInput("yourfile.txt");
  //`this` is the reference to you Activity or Context

Example:

FileInputStream in = openFileInput("filename.txt");
InputStreamReader inputStreamReader = new InputStreamReader(in);
BufferedReader bufferedReader = new BufferedReader(inputStreamReader);
StringBuilder sb = new StringBuilder();
String line;
while ((line = bufferedReader.readLine()) != null) {
    sb.append(line);
}

more details here