saving a text or CSV file with strings from edittext

Question

I need a simple app making a text file (.txt) in the phone (root or SD card) with inside various strings from more edittext. A button confirms the input data.

An example of output in the file must be:

output.txt

John ; Smith ; 10/05/1970 ; 

I'm interested also to export the data to a CSV file. This is the code:

MainActivity.java

package com.example.utente.questionario;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);


    final EditText editText1 = (EditText) findViewById(R.id.editText1);
    final EditText editText2 = (EditText) findViewById(R.id.editText2);
    final EditText editText3 = (EditText) findViewById(R.id.editText3);
    final Button button1 = (Button) findViewById(R.id.button1);


    }
}

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.example.utente.questionario.MainActivity">

<EditText
    android:id="@+id/editText1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:ems="10"
    android:inputType="textPersonName"
    android:hint="Name"
    android:layout_marginTop="74dp"
    android:layout_alignParentTop="true"
    android:layout_centerHorizontal="true" />

<EditText
    android:id="@+id/editText2"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:ems="10"
    android:inputType="textPersonName"
    android:hint="Surname"
    android:layout_below="@+id/editText1"
    android:layout_alignStart="@+id/editText1"
    android:layout_marginTop="42dp" />

<TextView
    android:id="@+id/textView3"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Birth date"
    android:textSize="18dp"
    android:layout_marginBottom="67dp"
    android:layout_above="@+id/button1"
    android:layout_centerHorizontal="true" />

<Button
    android:id="@+id/button1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Generate file"
    android:layout_alignParentBottom="true"
    android:layout_centerHorizontal="true"
    android:layout_marginBottom="90dp" />

<EditText
    android:id="@+id/editText3"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:ems="10"
    android:inputType="date"
    android:hint="dd/mm/yyyy"
    android:layout_centerVertical="true"
    android:layout_alignStart="@+id/editText2" />

</RelativeLayout>

Update: MainActivity.java after Riten's answer:

package com.example.utente.questionario;

import android.content.Context;
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;

import java.io.File;
import java.io.OutputStreamWriter;
import java.io.FileOutputStream;

public class MainActivity extends AppCompatActivity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    final EditText editText1 = (EditText) findViewById(R.id.editText1);
    final EditText editText2 = (EditText) findViewById(R.id.editText2);
    final EditText editText3 = (EditText) findViewById(R.id.editText3);
    final Button button1 = (Button) findViewById(R.id.button1);

    String name = editText1.getText().toString();
    String surname = editText2.getText().toString();
    String birthDate = editText3.getText().toString();

    private String getOrderText(String aa, String bb, String cc){

        StringBuilder sb = new StringBuilder();
        sb.append(aa+ ";");
        sb.append(" " + bb+ ";");
        sb.append(" " + cc);

            return sb.toString();
    }

    try {
        FileOutputStream fileOut=openFileOutput("FileName.txt", MODE_APPEND); // you can directly give file name as FileName.csv
        OutputStreamWriter outputWriter=new OutputStreamWriter(fileOut);
        outputWriter.write(getOrderText(name, surname, birthDate));
        outputWriter.write("\n");
        outputWriter.close();

    } catch (Exception e) {
        e.printStackTrace();
    }

Answer 1

You can simply try this:

 try {
        FileOutputStream fileOut=openFileOutput("FileName.txt", MODE_APPEND); // you can directly give file name as FileName.csv
        OutputStreamWriter outputWriter=new OutputStreamWriter(fileOut);
        outputWriter.write(getOrderText("string from edittext", "string from edittext", "string from edittext"));
        outputWriter.write("\n");
        outputWriter.close();

    } catch (Exception e) {
        e.printStackTrace();
    }

Then getOrderText can be defined as :

 private String getOrderText(String aa, String bb, String cc){

    StringBuilder sb = new StringBuilder();
    sb.append(aa+ ";");
    sb.append(" " + bb+ ";");
    sb.append(" " + cc);

    return sb.toString();
}

Hope this can help you ...