[JAVA] The basics of the process of making a call with an Android app

The basics of the process of making a call with an Android app

I had somehow implemented the process of making a call with the Android app, so I would like to describe it here again and take revenge on my own.

• The main purpose is to create opportunities for daily review and learning, and to establish knowledge through output. I hope you can see it with warm eyes.

How to make a call from the Android app

How to use Intent's ACTION_CALL

By using ACTION_CALL of Intent, you can make a call with the number entered on the application side.

• Manifest requires permission CALL_PHONE permission is required in the manifest.

How to use Intent's ACTION_DIAL

By using Intent's ACTION_DIAL, you can open the dialer and phone app with the number entered on the app side.

• Difference between ACTION_CALL and ACTION_DIAL ACTION_CALL: The call is received immediately ACTION_DIAL: Just open the phone app dialer. From there, you need to make a call (tap) on the phone app / dialer side.

Get permission for Dangerous permissions

The concept of permissions has changed since Android 6.0, and it has been divided into two types: permissions that require permissions for users and permissions that do not.

※review -Nomal permission: When installing the app, permission can be obtained based on the description in AndroidManifest.xml. -Dangerous permission: Permission can be obtained with the permission of the user. The authority can be revoked later by the user.

There are also Dangerous permissions related to the phone (permissions that belong to the permission group PHONE), so let's set to get the necessary permissions according to the purpose.

Basic code

   Intent intent = new Intent(Intent.ACTION_CALL, Uri.parse("tel:012345678"));
   startActivity(intent);

• Manifest also requires permission

AndroidManifest.xml

<uses-permission android:name="android.permission.CALL_PHONE" />

Processing at the time of error

You may not be able to connect because you do not have permission to connect to the dialog / phone application. With this basic code, in the case of an exception, the phone will not be connected and there will be no notification on the screen, and the user will not know what is going on.

Therefore, let's add exception handling and set to notify the user of the exception content at the time of exception.

• Alternatively, it is also possible to describe the process of checking the authority before startActivity (when you press the call button, first check the authority, if there is startActivity etc.)

   Intent intent = new Intent(Intent.ACTION_CALL, Uri.parse("tel:012345678"));

   //Exception handling from here
   try{
     startActivity(intent);
   }catch(e: SecurityException){
     Toast.makeText(context, "It's an error ...", Toast.LENGTH_SHORT).show()
   }

Summary

・ Get each authority in advance. ・ Let's make a call using Intent. -Implement exception handling in case of an error. -Let's build measures for users who try to make outgoing operations on the app even though they do not have permission.