Unit - 07 Making and Receiving Phone Calls

Lesson Plan: Unit - 07
Subject: P15A2AAD - Android Application Development
Topic of Study: Making and Receiving Phone Calls
Grade/Level: Master of Computer Applications
Objective: Making and Receiving Phone Calls
Time Allotment: 55 Minutes

• Making and Receiving Phone Calls
• The difference between dialing and calling:
• You can do this in two ways:
• Use an implicit Intent and ACTION_DIAL to launch the Phone app and display the phone number in the dialer.
• This is the simplest way, with no need to request permission from the user.
• The user can change the phone number before dialing the call.
• The user navigates back to your app using the Back button after the call is completed.
• Use an implicit Intent and ACTION_CALL to make the phone call directly from within your app.
• This action keeps the user within your app, without having to navigate back from the Phone app.
• Your code must ask the user for permission before making the call if the user hasn't already granted permission. 
• Your app can monitor the state of the phone call.
• Making Phone Calls:
• Phones are often still used for making and receiving phone calls.
• The Android SDK enables phone numbers to be passed to the dialer in two different ways.
• Way 01: The first way is to launch the dialer with a phone number already entered.
• The user then needs to press the Send button to actually initiate the call.
• This method does not require any specific permissions.
• Way 02:The second way is to actually place the call.
• This method requires the android.permission.CALL_PHONE permission to be added to the application’s AndroidManifest.xml file.
• Android provides Built-in applications for phone calls, in some occasions we may need to make a phone call through our application.
• Also, we can use PhoneStateListener and TelephonyManager classes, in order to monitor the changes in some telephony states on the device.
• Receving Phone Calls:
• An application can register to answer incoming phone calls.
• To enable this within an application, you must implement a broadcast receiver to process intents with the action Intent.ACTION_ANSWER.
• You can use the CallLog.calls class to determine recent call information, such as
• Who called
• When they called
• Whether it was an incoming or outgoing call
• Whether or not anyone answered
• The duration of the call
• Example: