Getting to Know the Android User Interface
Understanding The Components Of A Screen
? An activity displays the user interface of your
application, which may contain widgets such as
buttons, labels, textboxes, and so on.
? Typically, you define your UI using an XML fi le
(e.g., the main.xml file located in the res/layout
folder of your project)
During runtime, you load the XML UI in the
onCreate() method handler in your Activity
class,
? using the setContentView() method of the
Activity class:
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
}
During compilation, each element in the XML
file is compiled into its equivalent Android GUI
class, with attributes represented by methods.
? The Android system then creates the UI of the
activity when it is loaded
Views and ViewGroups
? An activity contains views and ViewGroups .
? One or more views can be grouped together
into a ViewGroup.
? A ViewGroup (which is itself a special type of
view) provides the layout in which you can
order the appearance and sequence of views.
المادة المعروضة اعلاه هي مدخل الى المحاضرة المرفوعة بواسطة استاذ(ة) المادة . وقد تبدو لك غير متكاملة . حيث يضع استاذ المادة في بعض الاحيان فقط الجزء الاول من المحاضرة من اجل الاطلاع على ما ستقوم بتحميله لاحقا . في نظام التعليم الالكتروني نوفر هذه الخدمة لكي نبقيك على اطلاع حول محتوى الملف الذي ستقوم بتحميله .
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