Multiple Activity and Navigation PrimerPresentation Transcript
Android Application Development Being Active Through Activities & Intents Ahsanul Karim [email_address] Sentinel Solutions Ltd. http://www.sentinelbd.com
Today We’re Covering…
Android Application Anatomy
Using Layouts from Activity
Activity to Activity Transition
Android Activities Activity Activity provides a user generally with an interactive screen to do something like: Dialing the phone, View a map List of something for user to select or Anything you want your user to do
An application usually consists of multiple activities.
Typically, one activity in an application is specified as the " main " activity, which is presented to the user when launching the application for the first time. (which is specified in AndroidMenifest.xml )
The <action> element specifies that this is the "main" entry point to the application. The <category> element specifies that this activity should be listed in the system's application launcher (to allow users to launch this activity).
Android Activities (Contd..) Creating Activity We have already created Activities. But how did we create it? Let’s revisit…
We created subclass of Activity base class
We implemented one callback method onCreate
What is creating subclass???
What is callback methods???
Android Activities (Contd..) Next Step: Implementing User Interface
Use Views from Activity class
Next Step: Implementing User Interface <manifest ... > <application ... > <activity android:name=".ExampleActivity" /> ... </application ... > ... </manifest > Next Step: Starting Activity Intent intent = new Intent(this, ToActivity.class); startActivity(intent); We can start another activity by calling startActivity() , passing it an Intent that describes the activity you want to start.
How to navigate from one Activity to another Intent Intent intent_1_to_2 = new Intent(this, Activity2.class); startActivity(intent_1_to_2); Intent Intent intent_2_to_1 = new Intent(this, Activity1.class); startActivity(intent_2_to_1);
Android Activities Exercise (Contd.) How to navigate from one Activity to another Intent Intent intent1to2 = new Intent(this, Activity2.class); startActivity(intent1to2); Intent Intent intent2to1 = new Intent(this, Activity1.class); startActivity(intent2to1);