Lecture 14: Bound Services

Question 1

Services may be ___, ___ or both depending on the circumstances

Answer 1

• started
• bound

Question 2

Boud services define the ___ and ___ lifecycle functions, but can also define an ___ method

Answer 2

• onBind()
• onUnbind()
• onStartCommand()

Question 3

We can think of a bound service as a form of __ relationship

Answer 3

client-server

Question 4

The bound service represents the __, while the activities that are bound to it act like ___

Answer 4

• server
• clients

Question 5

The purpose of a bound service is to allow a client to ___, or ___

Answer 5

• pass to or from the service
• call methods defined within the service

Question 6

The simplest way to create a bound service is to use the ____, but this has some limitations

Answer 6

extend the existing Binder interface

Question 7

The binder class is a form of ___ meaning it allows ___

Answer 7

• RPCC (Remote Procedural Call)
• one process to remotely call methods in another process

Question 8

Bound services that use the Binder interface can only be bound to ___ within the same ___

Answer 8

• activities/services/etc
• same application

Question 9

If you want to bind your service to an external activity/service you’ll need a ____

Answer 9

Messager

Question 10

To set up a service to accept bindings you need a ___variable that contains an ___

Answer 10

• class
• extended instance of a Binder

Question 11

onBind() returns the ___

Answer 11

binder object to the client for binding

Question 12

The LocalBinder is an extension of Binder and implements one class: ___, which provides the ___

Answer 12

• getService()
• client with a local reference to the running service

Question 13

When an activity is performing the bind we need to keep track of a few things.

We need a class reference to ____ and a ServiceConnection object to ___

Answer 13

• keep track of the service
• manage the binding on the activity side

Question 14

The ServieConnection has a callback which we can use to set the ___ and change the ___

Answer 14

• LocalService reference
• binding status of the application

Question 15

Within the Activity, a callback is created with a ___ thats used to handle the actual binding and unbinding procedure

Answer 15

ServiceConnection

Question 16

The ServiceConnection object defines __ and __ methods which we use to set/unset the service and bound refs

Answer 16

• onServiceConnected
• onServiceDisconnected

Question 17

Once we have a valid reference to the service, we can call __ belonging to that service directly from the reference

Answer 17

public methods

Question 18

boundRef provides a simple Boolean check to see if the service is ___

Answer 18

bound and available (skipping if its not)

Question 19

The code in the onServiceConnected() method is what takes the ___ from the service and calls the ___ method we defined back in the LocalBinder class

Answer 19

• binder
• getService()

Question 20

A service created through binding will cease to exist once ___

Answer 20

all bound connections are closed

Question 21

If you only have one activity bound to the service and it ever unbinds your service will ___

Answer 21

terminate and any persistent storage or data it might have contained is gone

Question 22

Its possible for a service to define both ___ methods and __ methods, meaning it can be launched bound or unbound

Answer 22

• starting
• binding

Question 23

If a service is launched as unbound and then later bound, it follows the ___ – it will not ___ when unbound

Answer 23

• unbound lifecycle
• automatically terminate

Question 24

Fundamentally binding a service just means youre allowing other participants (activities, services,etc) to ____

Answer 24

call methods contained within the service