Create Instant Alarm Android App Using Android Studio

Introduction

In this article, I will show you how to create an Instant Alarm Android App using Android studio.  

Requirements

• Android Studio version 2.3.3
• Little bit XML and JAVA knowledge.
• Android Emulator (or) Android mobile
• Download link (Android Studio)

Steps should be followed

Follow these steps to create an instant Alarm Android app. I have included the source code below.

Step 1

Open Android Studio and start a new Android Studio Project.

Step 2

You can choose your application name and choose where your project is stored. If you wish to use C++ for coding the project, mark the "Include C++ support", and click "Next" button.

Step 3

Now, select the version of Android and select the target Android devices. We need to choose the SDK level which plays an important role to run the application.

Step 4

Now, add the activity and click "Next" button.

Step 5

Add Activity name and click "Finish".

Step 6

Go to activity_main.xml. This XML file contains the designing code for the Android app.



The XML code is given below.

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity" >

    <EditText
        android:id="@+id/time"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_alignParentTop="true"
        android:layout_marginTop="28dp"
        android:ems="10"
        android:hint="Number of minutes"
        android:inputType="numberDecimal" />

    <Button
        android:id="@+id/button1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignRight="@+id/time"
        android:layout_below="@+id/time"
        android:layout_marginRight="60dp"
        android:layout_marginTop="120dp"
        android:text="Start" />

</RelativeLayout>

Step 7

Create a new java class file. Go to (Java ⇒ new ⇒Java class file).



Add the below code.

package abu.alarm;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.media.MediaPlayer;
import android.widget.Toast;

public class MyBroadcastReceiver extends BroadcastReceiver {
    MediaPlayer mp;
    @Override
    public void onReceive(Context context, Intent intent) {
        mp=MediaPlayer.create(context, R.raw.alrm   );
        mp.start();
        Toast.makeText(context, "Alarm....", Toast.LENGTH_LONG).show();
    }
}

Step 8

Add Music in Res folder. The below template shows how to add the image file. Go to app and right click. The “Show in Explorer” option  will appear. Click on the path and add the image in main folder.

Create a new folder, name it as “Raw”, and add the music (mp3) file.

Step 9

We need to make Vibrate requests, so add Vibrate permission in AndroidManifest.xml.



The AndroidManifest.xml code is given below.

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="abu.alarm">
    <uses-permission android:name="android.permission.VIBRATE" />
    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <receiver android:name="MyBroadcastReceiver" >
        </receiver>
    </application>

</manifest>

Step 10

Go to Main Activity.java. This Java program is the backend language for Android.



The Java code is given below.

package abu.alarm;

import android.app.Activity;
import android.app.AlarmManager;
import android.app.PendingIntent;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class MainActivity extends Activity {
    Button b1;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        b1=(Button) findViewById(R.id.button1);

        b1.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                startAlert();
            }
        });

    }   public void startAlert() {
        EditText text = (EditText) findViewById(R.id.time);
        int i = Integer.parseInt(text.getText().toString());
        Intent intent = new Intent(this, MyBroadcastReceiver.class);
        PendingIntent pendingIntent = PendingIntent.getBroadcast(
                this.getApplicationContext(), 234324243, intent, 0);
        AlarmManager alarmManager = (AlarmManager) getSystemService(ALARM_SERVICE);
        alarmManager.set(AlarmManager.RTC_WAKEUP, System.currentTimeMillis()
                + (i * 1000), pendingIntent);
        Toast.makeText(this, "Alarm set in " + i + " seconds",Toast.LENGTH_LONG).show();
    }

}

Step 11

Now, go to menu bar and click "Make Project" or press ctrl+f9 to debug the error.

Step 12

Then, click Run button or press shift+f10 to run the project. And choose the virtual machine and click OK.



Conclusion

We have successfully created  Instant Alarm Android application using Android Studio.