Creating a Notepad application in Android

ASH

9 years ago

Hi friends, today I will be showing you how you can create an Android application which can save your Notes. This is just a test application which I made in my spare time. I thought it will great to share code with you guys, so here it is.

Do comment below on what you guys think. Also it will be a long post, so bare with me friends.

So first things first make an Android Application in Android studio or Eclipse ADT and give it a name you desire. I named it Simple Notepad.

Layout files :

create three layout files in the res>layout folder and give name as follows :

listtemplate.xml –> This file will work as template to our Listview used to display saved notes.
notedisplay.xml –> This file will display the saved notes in our application.
viewnotepad.xml –> This file will show the note content.

Open the notedisplay.xml file and make changes as following :

notedisplay.xml :

<android.support.design.widget.CoordinatorLayout 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:id="@+id/coordinatorLayout"
 android:layout_width="match_parent"
 android:layout_height="match_parent"
 >

 <android.support.design.widget.AppBarLayout
 android:layout_width="match_parent"
 android:layout_height="wrap_content"
 android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar">

 <android.support.v7.widget.Toolbar
 android:id="@+id/toolbar"
 android:layout_width="match_parent"
 android:layout_height="?attr/actionBarSize"
 android:background="?attr/colorPrimary"
 app:layout_scrollFlags="scroll|enterAlways"
 app:popupTheme="@style/ThemeOverlay.AppCompat.Light" />
 </android.support.design.widget.AppBarLayout>

 <RelativeLayout
 android:layout_width="match_parent"
 android:layout_height="match_parent"
 android:background="#5eaeff"
 android:paddingTop="5dp"
>

 <ListView
 android:id="@+id/listView1"
 android:dividerHeight="2dp"
 android:layout_width="match_parent"
 android:layout_height="wrap_content"
 android:layout_alignParentTop="true" >
 </ListView>

</RelativeLayout>
 <android.support.design.widget.FloatingActionButton
 android:id="@+id/btnadd"
 android:layout_width="wrap_content"
 android:layout_height="wrap_content"
 android:layout_gravity="end|bottom"
 android:layout_margin="16dp"
 android:src="@drawable/plus" />
 </android.support.design.widget.CoordinatorLayout>

The layout contains Listview (listview1) field to display the saved notes. And a floating action button to add new notes.

Now edit the listtemplate.xml file as following :

listtemplate.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 android:layout_width="match_parent"
 android:layout_height="50dp"
 android:background="#ffffff"
 android:orientation="vertical"
 android:weightSum="2" >

 <LinearLayout
 android:layout_width="match_parent"
 android:layout_height="0dp"
 android:layout_weight="1"
 android:orientation="horizontal"
 android:weightSum="2" >

 <TextView
 android:id="@+id/txtnamerow"
 android:layout_width="0dp"
 android:layout_height="wrap_content"
 android:layout_marginLeft="5dp"
 android:layout_weight="1.2"
 android:text="name"
 android:textColor="#000000"
 android:textSize="20sp" />

 <TextView
 android:id="@+id/txtidrow"
 android:layout_width="0dp"
 android:layout_height="wrap_content"
 android:layout_weight="0"
 android:visibility="gone" />

 <TextView
 android:id="@+id/txtdate"
 android:layout_width="0dp"
 android:layout_height="wrap_content"
 android:layout_marginRight="5dp"
 android:layout_weight="0.8"
 android:gravity="right"
 android:text="2/2/2015" />
 </LinearLayout>

 <LinearLayout
 android:layout_width="match_parent"
 android:layout_height="0dp"
 android:layout_weight="1"
 android:orientation="vertical"
 android:weightSum="2" >

 <TextView
 android:id="@+id/txtremark"
 android:layout_width="match_parent"
 android:layout_height="0dp"
 android:layout_marginLeft="15dp"
 android:layout_marginRight="15dp"
 android:layout_marginTop="5dp"
 android:layout_weight="2"
 android:maxHeight="50dp"
 android:text="fgvgvkjdvmldngvmdngvmrfrfmmgbn"
 android:textSize="15sp"
 android:visibility="gone" />
 </LinearLayout>

</LinearLayout>

This file will make up our Listview for displaying saved notes. The layout contains four textview (txtnamerow, txtidrow, txtdate and txtremark) out of which two are hidden from the user. You will understand the purpose later of doing such a thing.

Now open the viewnotepad.xml file and make changes as below :

viewnotepad.xml


<android.support.design.widget.CoordinatorLayout 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:id="@+id/coordinatorLayout"
 android:layout_width="match_parent"
 android:layout_height="match_parent"
 >

 <android.support.design.widget.AppBarLayout
 android:layout_width="match_parent"
 android:layout_height="wrap_content"
 android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar">

 <android.support.v7.widget.Toolbar
 android:id="@+id/toolbar"
 android:layout_width="match_parent"
 android:layout_height="?attr/actionBarSize"
 android:background="?attr/colorPrimary"
 app:layout_scrollFlags="scroll|enterAlways"
 app:popupTheme="@style/ThemeOverlay.AppCompat.Light" />
 </android.support.design.widget.AppBarLayout>


<LinearLayout
 android:id="@+id/scrollView1"
 android:layout_width="match_parent"
 android:layout_height="match_parent"
 android:orientation="vertical"
 android:weightSum="10"

 >

 <LinearLayout
 android:layout_width="match_parent"
 android:layout_height="0dp"
 android:layout_weight="1"
 android:orientation="horizontal"
 android:weightSum="2" >

 <TextView
 android:id="@+id/textView1"
 android:layout_width="0dp"
 android:layout_height="wrap_content"
 android:layout_weight="0.5"
 android:gravity="top|center"
 android:text="NAME" />

 <EditText
 android:id="@+id/txtname"
 android:layout_width="0dp"
 android:layout_height="wrap_content"
 android:gravity="top|center"
 android:inputType="textAutoCorrect"
 android:hint="Name of note here"
 android:layout_weight="1.5"
 >
 </EditText>
 </LinearLayout>

 <LinearLayout
 android:layout_width="match_parent"
 android:layout_height="0dp"
 android:layout_weight="9"
 android:orientation="vertical"
 android:weightSum="2" >

 <EditText
 android:id="@+id/txtcontent"
 android:hint="Your text here"
 android:gravity="top|left"
 android:layout_width="match_parent"
 android:layout_height="0dp"
 android:layout_weight="2"
 android:inputType="textMultiLine">
 </EditText>
 </LinearLayout>

</LinearLayout>
</android.support.design.widget.CoordinatorLayout>

This layout contains two edittext control which will display the note name and its content.And finally the layout part is ready.

Open the res>values folder of your project :

First edit the colors.xml file as following :

colors.xml :

<?xml version="1.0" encoding="utf-8"?>
<resources>
 <color name="colorPrimary">#0080ff</color>
 <color name="colorPrimaryDark">#125688</color>
 <color name="textColorPrimary">#FFFFFF</color>
 <color name="windowBackground">#FFFFFF</color>
 <color name="navigationBarColor">#000000</color>
 <color name="colorAccent">#fff</color>
</resources>

Now edit the styles.xml file as following :

styles.xml :

<resources>
<!-- Base application theme. -->
 <style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">
 <item name="windowNoTitle">false</item>
 <item name="windowActionBar">true</item>
 <item name="colorPrimary">@color/colorPrimary</item>
 <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
 <item name="colorAccent">@color/colorAccent</item>
 </style></resources>

Now in strings.xml file add following variable :

strings.xml :

<resources>
 <string name="app_name">Simple Notepad</string>

<string name="hello_world">Hello world!</string>
 <string name="action_settings">Settings</string>
 <string name="DeleteNote">Are you Sure?</string>
</resources>

In the res>menu folder add new file named display_menu.xml and edit it as following :

display_menu.xml :

<menu 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">
 <item
 android:id="@+id/Save"
 android:orderInCategory="100"
 android:title="SAVE"
 app:showAsAction="always"/>
 <item
 android:id="@+id/Delete"
 android:orderInCategory="100"
 android:title="delete"/>
</menu>

And add another file named menu_main.xml in the res>menu folder, if it’s not present.

menu_main.xml:

<menu 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">
 <item
 android:id="@+id/add"
 android:orderInCategory="100"
 android:title="Add new"
 app:showAsAction="always|withText"/>
</menu>

And finally the design part is ready. In the next post I’ll be showing the coding part.

Coding the Notepad application:

This is a continuation post of my post on making a simple notepad application in Android.

Make a new class in your project with name NDb.java. This class will the database class.Creating the database, getting the content of the particular note from the database and getting all the notes from the database will be done by this class.

Extend this class with SQLiteOpenHelper class.

package hitesh.simplenotepad;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.DatabaseUtils;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import java.util.ArrayList;
import java.util.HashMap;
public class NDb extends SQLiteOpenHelper {

In this class make following variables:

public static final String dbname = "MyNotes.db";
 public static final String _id = "_id";
 public static final String name = "name";
 public static final String remark = "remark";
 public static final String dates = "dates";
 public static final String mynotes = "mynotes";
private HashMap hp;
 SQLiteDatabase db;

and this :

public NDb(Context context) {
 super(context, dbname, null, 1);
 }

in the onCreate method run the script for creating the database.

Override
 public void onCreate(SQLiteDatabase db) {
 // TODO Auto-generated method stub
 db.execSQL("create table mynotes"
 + "(_id integer primary key, name text,remark text,dates text)");
 }
@Override
 public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
 // TODO Auto-generated method stub
 db.execSQL("DROP TABLE IF EXISTS " + mynotes);
 onCreate(db);
 }

And create this method of getting the data and retrieving the data from the database :

public Cursor fetchAll() {
 db = this.getReadableDatabase();
 Cursor mCursor = db.query(mynotes, new String[] { "_id", "name",
 "dates", "remark" }, null, null, null, null, null);
if (mCursor != null) {
 mCursor.moveToFirst();
 }
 return mCursor;
 }
public boolean insertNotes(String name, String dates, String remark) {
 SQLiteDatabase db = this.getWritableDatabase();
 ContentValues contentValues = new ContentValues();
 contentValues.put("name", name);
 contentValues.put("dates", dates);
 contentValues.put("remark", remark);
db.insert(mynotes, null, contentValues);
 return true;
 }

public Cursor getData(int id) {
 SQLiteDatabase db = this.getReadableDatabase();
 Cursor z = db.rawQuery("select * from " + mynotes + " where _id=" + id
 + "", null);
return z;
 }
public int numberOfRows() {
 SQLiteDatabase db = this.getReadableDatabase();
 int numRows = (int) DatabaseUtils.queryNumEntries(db, mynotes);
 return numRows;
 }
public boolean updateNotes(Integer id, String name, String dates,
 String remark) {
 SQLiteDatabase db = this.getWritableDatabase();
 ContentValues contentValues = new ContentValues();
 contentValues.put("name", name);
 contentValues.put("dates", dates);
 contentValues.put("remark", remark);
 db.update(mynotes, contentValues, "_id = ? ",
 new String[] { Integer.toString(id) });
 return true;
 }
public Integer deleteNotes(Integer id) {
 SQLiteDatabase db = this.getWritableDatabase();
 return db.delete(mynotes, "_id = ? ",
 new String[] { Integer.toString(id) });
 }
public ArrayList getAll() {
 ArrayList array_list = new ArrayList();
 SQLiteDatabase db = this.getReadableDatabase();
 Cursor res = db.rawQuery("select * from " + mynotes, null);
 res.moveToFirst();
 while (res.isAfterLast() == false) {
 array_list.add(res.getString(res.getColumnIndex("_id")));
 array_list.add(res.getString(res.getColumnIndex(remark)));
 array_list.add(res.getString(res.getColumnIndex(dates)));
 array_list.add(res.getString(res.getColumnIndex(name)));
 res.moveToNext();
 }
 return array_list;
 }

Create a new class file with name MyNotes.java and edit it as following :

MyNotes.java :

package hitesh.simplenotepad;
import android.app.AlertDialog;
import android.content.Context;
import android.content.Intent;
import android.database.Cursor;
import android.os.Bundle;
import android.support.design.widget.CoordinatorLayout;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.SimpleCursorAdapter;
import android.widget.TextView;
public class MyNotes extends AppCompatActivity {
 private ListView obj;
 NDb mydb;
 FloatingActionButton btnadd;
 ListView mylist;
 Menu menu;
 AlertDialog.Builder alertDialogBuilder;
 AlertDialog alertDialog;
 Context context = this;
 CoordinatorLayout coordinatorLayout;
SimpleCursorAdapter adapter;
 Snackbar snackbar;
 @Override
 protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.notedisplay);
 coordinatorLayout = (CoordinatorLayout) findViewById(R.id.coordinatorLayout);
 mydb = new NDb(this);
 btnadd = (FloatingActionButton) findViewById(R.id.btnadd);
 btnadd.setOnClickListener(new View.OnClickListener() {
 @Override
 public void onClick(View v) {
 Bundle dataBundle = new Bundle();
 dataBundle.putInt("id", 0);
 Intent intent = new Intent(getApplicationContext(),
 DisplayNote.class);
 intent.putExtras(dataBundle);
 startActivity(intent);
 finish();
}
 });
 Cursor c = mydb.fetchAll();
 String[] fieldNames = new String[] { NDb.name, NDb._id, NDb.dates, NDb.remark };
int[] display = new int[] { R.id.txtnamerow, R.id.txtidrow,
 R.id.txtdate,R.id.txtremark };
 adapter = new SimpleCursorAdapter(this, R.layout.listtemplate, c, fieldNames,
 display, 0);
snackbar = Snackbar
 .make(coordinatorLayout, "You are awesome I think!", Snackbar.LENGTH_LONG);
 snackbar.show();
mylist = (ListView) findViewById(R.id.listView1);
 mylist.setAdapter(adapter);
 mylist.setOnItemClickListener(new OnItemClickListener() {
@Override
 public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
 long arg3) {
 LinearLayout linearLayoutParent = (LinearLayout) arg1;
 LinearLayout linearLayoutChild = (LinearLayout) linearLayoutParent
 .getChildAt(0);
 TextView m = (TextView) linearLayoutChild.getChildAt(1);
Bundle dataBundle = new Bundle();
 dataBundle.putInt("id",
 Integer.parseInt(m.getText().toString()));
 Intent intent = new Intent(getApplicationContext(),
 DisplayNote.class);
 intent.putExtras(dataBundle);
 startActivity(intent);
 finish();
 }
 });
 }
@Override
 public boolean onCreateOptionsMenu(Menu menu) {
 getMenuInflater().inflate(R.menu.menu_main, menu);
 this.menu = menu;
 return true;
 }
@Override
 public boolean onOptionsItemSelected(MenuItem item) {
 super.onOptionsItemSelected(item);
 switch (item.getItemId()) {
 case R.id.add:
 Bundle dataBundle = new Bundle();
 dataBundle.putInt("id", 0);
 Intent intent = new Intent(getApplicationContext(),
 DisplayNote.class);
 intent.putExtras(dataBundle);
 startActivity(intent);
 finish();
 return true;
 default:
 return super.onOptionsItemSelected(item);
}
 }
}

Create another class file in your project with name DisplayNote.java and edit it as following :

DisplayNote.java :

package hitesh.simplenotepad;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.database.Cursor;
import android.os.Bundle;
import android.support.design.widget.CoordinatorLayout;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.EditText;
import android.widget.Toast;
import java.text.SimpleDateFormat;
import java.util.Calendar;
public class DisplayNote extends AppCompatActivity {
private NDb mydb;
 EditText name;
 EditText content;
 private CoordinatorLayout coordinatorLayout;
 String dateString;
 Bundle extras;
 int id_To_Update = 0;
 Snackbar snackbar;
 @Override
 protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.viewnotepad);
 name = (EditText) findViewById(R.id.txtname);
 content = (EditText) findViewById(R.id.txtcontent);
 coordinatorLayout = (CoordinatorLayout) findViewById(R.id
 .coordinatorLayout);
 mydb = new NDb(this);
 Bundle extras = getIntent().getExtras();
 if (extras != null) {
 int Value = extras.getInt("id");
 if (Value > 0) {
 snackbar = Snackbar
 .make(coordinatorLayout, "Note Id : "+String.valueOf(Value), Snackbar.LENGTH_LONG);
 snackbar.show();
 Cursor rs = mydb.getData(Value);
 id_To_Update = Value;
 rs.moveToFirst();
String nam = rs.getString(rs.getColumnIndex(NDb.name));
 String contents = rs.getString(rs.getColumnIndex(NDb.remark));
if (!rs.isClosed()) {
 rs.close();
 }
name.setText((CharSequence) nam);
 content.setText((CharSequence) contents);
}
 }
 }
@Override
 public boolean onCreateOptionsMenu(Menu menu) {
 Bundle extras = getIntent().getExtras();
 if (extras != null) {
 int Value = extras.getInt("id");
getMenuInflater().inflate(R.menu.display_menu, menu);
}
 return true;
 }
public boolean onOptionsItemSelected(MenuItem item) {
 super.onOptionsItemSelected(item);
 switch (item.getItemId()) {
case R.id.Delete:
AlertDialog.Builder builder = new AlertDialog.Builder(this);
 builder.setMessage(R.string.DeleteNote)
 .setPositiveButton("YES",
 new DialogInterface.OnClickListener() {
 public void onClick(DialogInterface dialog,
 int id) {
 mydb.deleteNotes(id_To_Update);
Toast.makeText(DisplayNote.this, "Deleted Successfully",Toast.LENGTH_SHORT).show();
 Intent intent = new Intent(
 getApplicationContext(),
 MyNotes.class);
 startActivity(intent);
 finish();
 }
 })
 .setNegativeButton("NO",
 new DialogInterface.OnClickListener() {
 public void onClick(DialogInterface dialog,
 int id) {

}
 });
 AlertDialog d = builder.create();
 d.setTitle("Are you sure");
 d.show();
return true;
 case R.id.Save:
 Bundle extras = getIntent().getExtras();
 Calendar c = Calendar.getInstance();
 System.out.println("Current time => " + c.getTime());
SimpleDateFormat df = new SimpleDateFormat("dd-MMM-yyyy");
 String formattedDate = df.format(c.getTime());
 dateString = formattedDate;
 if (extras != null) {
 int Value = extras.getInt("id");
 if (Value > 0) {
 if (content.getText().toString().trim().equals("")
 || name.getText().toString().trim().equals("")) {
snackbar = Snackbar
 .make(coordinatorLayout, "Please fill in name of the note", Snackbar.LENGTH_LONG);
 snackbar.show();
 } else {
 if (mydb.updateNotes(id_To_Update, name.getText()
 .toString(), dateString, content.getText()
 .toString())) {
snackbar = Snackbar
 .make(coordinatorLayout, "Your note Updated Successfully!!!", Snackbar.LENGTH_LONG);
 snackbar.show();
} else {
snackbar = Snackbar
 .make(coordinatorLayout, "There's an error. That's all I can tell. Sorry!", Snackbar.LENGTH_LONG);
 snackbar.show();
 }
 }
 } else {
 if (content.getText().toString().trim().equals("")
 || name.getText().toString().trim().equals("")) {
 snackbar = Snackbar
 .make(coordinatorLayout, "Please fill in name of the note", Snackbar.LENGTH_LONG);
 snackbar.show();
} else {
 if (mydb.insertNotes(name.getText().toString(), dateString,
 content.getText().toString())) {
snackbar = Snackbar
 .make(coordinatorLayout, "Added Successfully.", Snackbar.LENGTH_LONG);
 snackbar.show();
 } else {
 snackbar = Snackbar
 .make(coordinatorLayout, "Unfortunately Task Failed.", Snackbar.LENGTH_LONG);
 snackbar.show();
}
 }
 }
 }
 return true;
 default:
 return super.onOptionsItemSelected(item);
}
}
 @Override
 public void onBackPressed() {
 Intent intent = new Intent(
 getApplicationContext(),
 MyNotes.class);
 startActivity(intent);
 finish();
 return;
 }
}

This class file will be used to see the notes content and editing the note, updating it and deleting it.

AndroidManifest.xml:

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
 package="hitesh.simplenotepad" >
<application
 android:allowBackup="true"
 android:icon="@mipmap/ic_launcher"
 android:label="@string/app_name"
 android:theme="@style/AppTheme" >
 <activity
 android:name=".MyNotes"
 android:screenOrientation="portrait"
 android:label="@string/app_name" >
 <intent-filter>
 <action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
 </intent-filter>
 </activity>
 <activity
 android:name=".DisplayNote"
 android:screenOrientation="portrait"
 android:label="@string/app_name" />
 </application>
</manifest>

If you have any questions or queries please mention below in the comment section. Happy to hear from you guys.

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