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Uploaded byMayank Bhatt
Android application development
The document covers the fundamentals of Android application development, focusing on views, view groups, layouts, event handling, and activity implementation. It describes how to manage user interface components and interaction through various classes, including common layout classes and intent types. Additionally, it outlines the lifecycle of an activity and the significance of handling events in the application context.
Android application development
- 1. ANDROID APPLICATION DEVELOPMENT Submitted By- MayankBhatt SubmittedTo- Ms. Niharika Joshi
- 2. Content • Views • Usingviews • View groups • Layout • Common layout classes • Event handling • Activity • Implementing activities • Intent • Activity states and App visibility
- 3. Views • Views areandroid’s basic user interface building blocks • Base class for widgets • Responsible for drawing and event handling
- 4. UsingViews • Set properties •Set focus • Set up listeners • Set visibility
- 5. View groups • Containsother views. • Base class for layouts and view containers • This class also defines theViewGroup.LayoutParams class
- 6. Layout • Specific typesof view groups • Subclasses of view groups • Contains child views
- 7. Common layout classes •Constraint layout • Linear layout • Relative layout • Table layout • Grid layout
- 8. Event handling • InXML: • Attach handler to view in layout • android: onClick=“ShowToast” • Implementing handler in activity public void showToast(View view){ String msg=“Hello”; Toast toast =Toast.makeText(this,msg,duration) toast.Show(); }
- 9. • Setting clickhandlers in Java final Button button = (Button)findViewById(R.id.button_id); button.SetOnClickListener(newView.OnClickListener(){ public void OnClick(View v){ String msg=“Hello !!!”; Toast toast =Toast.makeText(this,msg,duration); toast.show(); } })
- 10. Activity • An activityis an application component • An activity comprises of two things- • Java file • XML file • It is a class with U.I.
- 11. Implementing new activities 1.Define layout in XML 2. Define JAVA class 1. extends AppCompatActivity 3. Connect Activity with layout 1. Set content view in onCreate() 4. Declare Activity in android manifest file
- 16. Activity states andApp visibility • Created • Started • Resume • Paused • Stopped • Destroyed
- 17. Intent • An intentis a description of an operation to be performed. • An intent is an object used to request an operation from another app component.
- 18. What can Intentsdo? • Start activities • Start services • Deliver Broadcasts
- 19. Types Of Intents •Explicit Intent • These intents designate the target component by its name and they are typically used for application-internal messages • Implicit Intent • These intents do not name a target and the field for the component name is left blank.
- 20.
Editor's Notes
- #5 All of the views in a window are arranged in a single tree. You can add views either from code or by specifying a tree of views in one or more XML layout files. There are many specialized subclasses of views that act as controls or are capable of displaying text, images, or other content. Once you have created a tree of views, there are typically a few types of common operations you may wish to perform: Set properties: for example setting the text of a TextView. The available properties and the methods that set them will vary among the different subclasses of views. Note that properties that are known at build time can be set in the XML layout files. Set focus: The framework will handle moving focus in response to user input. To force focus to a specific view, call requestFocus(). Set up listeners: Views allow clients to set listeners that will be notified when something interesting happens to the view. For example, all views will let you set a listener to be notified when the view gains or loses focus. You can register such a listener using setOnFocusChangeListener(android.view.View.OnFocusChangeListener). Other view subclasses offer more specialized listeners. For example, a Button exposes a listener to notify clients when the button is clicked. Set visibility: You can hide or show views using setVisibility(int). Note: The Android framework is responsible for measuring, laying out and drawing views. You should not call methods that perform these actions on views yourself unless you are actually implementing a ViewGroup.
- #11 Whatever you see on screen all the ui they all are presented by activity. It can be a complete window , floating window
- #12 we create layout in layout folder which is inside res folder we need a java file which extends appcompatactivity we need to connect a XML file with java file that’s where onCreate method comes in
- #17 not visible, visible, visible , partially invisible, hidden, gone from memory
- #18 Intent is a class which is used to invoke all the android fundamental components(activities, services, broadcast receivers, content provider) except content provider.