Android GUI Developmentx - MCS

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14 Δεκ 2013 (πριν από 3 χρόνια και 10 μήνες)

214 εμφανίσεις

By: Jeremy Smith


Introduction


Droid Draw


Add XML file


Layouts


LinearLayout



RelativeLayout


Objects


Notifications


Toast


Status Bar


Dialog


Menus


Events


Listeners


Handlers


Focus


Source


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

folder.

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
()

RelativeLayout

LinearLayout


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:

1.
Reference the
NotificationManager
:


2.
Instantiate the Notification:




3.
Define the Notification's expanded message and Intent:





4.

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.


Examples


Allows users to access application functions and
settings.


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


http://developer.android.com/guide/topics/ui/
index.html