In the past, we've covered how to simulate receiving SMS messages on Android emulators. It is also possible to receive and interact with incoming phone calls! This might be relevant for apps that engage with the phone subsystem in some way, or it might just be a good idea to test that nothing goes wrong in your app when someone takes a call while using it.

(Of course, this only works on emulators; to achieve the same result on a real device, just make sure the real device has a working SIM card and trigger a call to it using one of the available phone call automation services.)

How can we take advantage of this feature? It's made available in the Appium Java client via the driver.makeGsmCall() method. This method takes two parameters:

1. A string representing the phone number which the emulator will show as calling it (this should be purely numbers, no dashes or parentheses).
2. A member of the GsmCallActions enum, namely one of GsmCallActions.CALL, GsmCallActions.CANCEL, GsmCallActions.ACCEPT, or GsmCallActions.HOLD. Each of these defines an action the emulator will take with respect to the particular phone number that has called.

Basically, to initiate a call to the emulator, we first make a call like this:

driver.makeGsmCall("1234567890", GsmCallActions.CALL);

This will start the device "ringing". At this point it will continue to ring until we follow up with another action. We may, for example, choose to accept the call:

driver.makeGsmCall("1234567890", GsmCallActions.ACCEPT);

At this point the call will be active, and will remain active until we choose to end it:

driver.makeGsmCall("1234567890", GsmCallActions.CANCEL);

Using this series of commands, we can simulate the entire flow of a user receiving a phone call while in our app, accepting the call, continuing to go about her business in the app while the call is active, and then ending the call. At any point in this flow we can continue to run regular Appium commands, which is how we would check that our app continues to function normally even as the call takes place.

That's it! Take a look at the full example below, which introduces some artificial pauses in the course of the script so you can see the action taking place (otherwise it all happens too quickly):

import io.appium.java_client.android.AndroidDriver;
import io.appium.java_client.android.GsmCallActions;
import java.net.MalformedURLException;
import java.net.URL;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import org.openqa.selenium.remote.DesiredCapabilities;

public class Edition042_Android_Phone {

    private AndroidDriver driver;
    private String APP = "https://github.com/cloudgrey-io/the-app/releases/download/v1.7.1/TheApp-v1.7.1.apk";
    private String PHONE_NUMBER = "5551237890";

    @Before
    public void setUp() throws MalformedURLException {
        DesiredCapabilities capabilities = new DesiredCapabilities();

        capabilities.setCapability("platformName", "Android");
        capabilities.setCapability("deviceName", "Android Emulator");
        capabilities.setCapability("automationName", "UiAutomator2");
        capabilities.setCapability("app", APP);

        driver = new AndroidDriver(new URL("http://localhost:4723/wd/hub"), capabilities);
    }

    @After
    public void tearDown() {
        if (driver != null) {
            driver.quit();
        }
    }

    @Test
    public void testPhoneCall() throws InterruptedException {
        // do something in our app
        driver.findElementByAccessibilityId("Login Screen").click();

        // receive and accept a call
        driver.makeGsmCall(PHONE_NUMBER, GsmCallActions.CALL);
        Thread.sleep(2000); // pause just for effect
        driver.makeGsmCall(PHONE_NUMBER, GsmCallActions.ACCEPT);

        // continue to do something in our app
        driver.findElementByAccessibilityId("username").sendKeys("hi");
        Thread.sleep(2000); // pause just for effect

        // end the call
        driver.makeGsmCall(PHONE_NUMBER, GsmCallActions.CANCEL);
        Thread.sleep(2000); // pause just for effect
    }
}

Of course, you can also have a look at the sample on GitHub.