Does it good code for TDD in Android?

I’ll try to understand how to use TDD in my Android apps.

How could look a test on Android with this user story: As a user I can send messages to support?

It seems like I must add some class SupportService, which can send messages. But I need to see good example for best understand.

Is it good code? Will I need remove interface and just paste SupportService object?

public MockitoRule mockitoRule = MockitoJUnit.rule();

ISupportService supportServiceMock;

public void testSendMessageToSupport (){
    String message = "message";

    boolean isSent = supportServiceMock.sendMessageToSupport(message);

    assertEquals("Sending message to support are failed.", true, isSent);

Seems like I tested nothing in this case…