Android GUI Development

By: Jeremy Smith
Droid Draw
Add XML file
 LinearLayout
 RelativeLayout
 Toast
 Status Bar
 Dialog
 Listeners
 Handlers
 Focus
In Android, the UI is built using View and
ViewGroup objects.
Views are a base for subclasses called
“Widgets,” which offer fully implemented UI
objects. (Ex. Text fields and buttons)
ViewGroups are a base for “layouts,” which
offer different kinds of layout architectures.
Android GUI’s are coded in a version of XML
and are based on the Views and ViewGroups.
Add an Android specific XML file to a project.
1. In your android project open up the res
2. Then open the layout folder and you will see
a generic file called main.xml
3. To add a XML file simply right click and add
a new file. Under Android select the Android
XML file and you have a brand new XML file
open to edit in your project.
Writing XML ( Android has its own XML vocabulary )
 Used for designing UI layouts and screen elements
Each layout must have only one root element. (parent)
 After you create an initial layout you can add additional layouts
and widgets to the layout. (child objects)
Position, Size, Padding and Margins
Ex. getLeft(), getHight(), getPadding()
The visual UI elements to be used on your
Application screen.
Includes Buttons, Images, dialog and many
other objects.
Interfaces & Classes
In the java source code
In the XML layout
For a situation where you may need to notify a user about
an event from your application
 3 Types
 Toast Notification
▪ Brief message that comes form the background
 Status Bar Notification
▪ Background reminders that request the user’s response
 Dialog Notification
▪ Activity-related notifications, sometimes require an user interaction.
Toast Notification
Status Bar Notification
Dialog Notification
Initiating a Toast object
 Initiate toast from the source code
 Or by chaining methods
How to create a status bar notification:
Reference the NotificationManager:
Instantiate the Notification:
Define the Notification's expanded message and Intent:
Pass the Notification to the NotificationManager:
Types of Dialogs
 AlertDialog
▪ Can have buttons, selectable items, and text dialog.
 ProgressDialog
▪ Displays a wheel or progress bar, also supports buttons.
 DatePickerDialog
▪ Allows user to select a date.
 TimePickerDialog
▪ Allows user to select a time.
 CustomDialogs
▪ Create your own dialog to suit your needs.
Allows users to access application functions and
 3 Types of menus
 Options Menu
▪ Appear when user presses the hard MENU button
▪ Two Types
▪ Icon Menu
▪ Expanded Menu
 Context Menu
▪ Floating list of menu items, appears after a long-press on an item.
 Submenu
▪ Floating list of menu items that the user opens by pressing a menu
item in the Options Menu or context menu.
 Example Menus

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