Mobile Application Development- Android-B.C.A 17-20-First-Internal-Exam-FEB-2020

1.       A software development kit (SDK) is a collection of software development tools in one installable package. They ease creation of applications by having compiler, debugger and perhaps a software framework. They are normally specific to a hardware platform and operating system combination.

2.        

<Button

       android:id="@+id/simpleButton2"

        android:layout_width="fill_parent"

        android:layout_height="wrap_content"

        android:layout_centerInParent="true"

        android:background="#f00"

        android:drawableLeft="@drawable/ic_launcher"

        android:hint="AbhiAndroid Button2"

        android:padding="5dp"

        android:textColorHint="#fff"

       android:textSize="20sp"

        android:textStyle="bold|italic" />

3.     Android is a stack of software for mobile devices that are an operating system, middleware and key Applications. It is a Linux-based operating system designed for smartphones. It is an open source operating system.

4.     ADT is a plugin for the Eclipse IDE which provides a suitable environment to develop an android application where creation, compilation and debugging are possible.

5.       In Android, Spinner is used to select one value from a set of values. In the default state, a spinner shows its currently selected value. Touching the spinner displays a drop down menu with all other available values, from which the user can select a new one. Android spinner is associated with AdapterView .

6.       Declaration file

7.        

JVM	DVM
1.     Support multiple operating System 2.     Compiles Java Byte code 3.     It forms separate classes in separate .class byte code file 4.     Based on Stack based 5.     Runs on more memory 6.     Executable format is .jar 7.     It has different constant pools 8.     JVM runs .class byte code directly.	1.     Only support Android OS 2.     Compiles Dalvik bytecode 3.     Forms multiple class in one .dex file 4.     Register based 5.     Less memory 6.     Executable format is .apk 7.     It has common constant pool 8.     .class byte codes are optimized to .odex format before executing in DVM

8.    RadioButton is a two states button which is either checked or unchecked. If a single radio button is unchecked, we can click it to make checked radio button. Once a radio button is checked, it cannot be marked as unchecked by user.

RadioButton is generally used with RadioGroup. RadioGroup contains several radio buttons, marking one radio button as checked makes all other radio buttons as unchecked.

Example program

9.    spinner

XML attributes
android:dropDownHorizontalOffset	Amount of pixels by which the drop down should be offset horizontally.
android:dropDownSelector	List selector to use for spinnerMode="dropdown" display.
android:dropDownVerticalOffset	Amount of pixels by which the drop down should be offset vertically.
android:dropDownWidth	Width of the dropdown in spinnerMode="dropdown".
android:gravity	Gravity setting for positioning the currently selected item.
android:popupBackground	Background drawable to use for the dropdown in spinnerMode="dropdown".
android:prompt	The prompt to display when the spinner's dialog is shown.
android:spinnerMode	Display mode for spinner options.

Textview

<TextView

      android:id="@+id/text_id"

      android:layout_width="300dp"

      android:layout_height="200dp"

      android:capitalize="characters"

      android:text="hello_world"

      android:textColor="@android:color/holo_blue_dark"

      android:textColorHighlight="@android:color/primary_text_dark"

      android:layout_centerVertical="true"

      android:layout_alignParentEnd="true"

      android:textSize="50dp"/>

10. Android Layout Attributes

android:id : This is the ID which uniquely identifies the view

android:layout_width : This is the width of the layout

android:layout_height : This is the height of the layout

android:layout_margin : This is the extra space outside of the view. For example if you give android:marginLeft=20dp, then the view will be arranged after 20dp from left

android:layout_padding : This is similar to android:layout_margin except that it specifies the extra space inside the view

android:layout_gravity : This specifies how child Views are positioned

android:layout_weight : This specifies how much of the extra space in the layout should be allocated to the view

android:layout_x : This specifies the x-coordinate of the layout

android:layout_y : This specifies the y-coordinate of the layout

linearlayout:-orientation

Relative:-  toLeftOf, toRightOf, below or above

11. Android ProgressBar is a graphical view indicator that shows some progress. Android progress bar displays a bar representing the completing of the task. Progress bar in android is useful since it gives the user an idea of time to finish its task.

Example program

12.  open source, Storage, Media Support, Streaming , Multitouch, web browser, video calling, multitasking, Accessibility, voice based features etc.(Expand any five feature)

13. Linux kernel

At the bottom of the layers is Linux - Linux 3.6 with approximately 115 patches. This provides a level of abstraction between the device hardware and it contains all the essential hardware drivers like camera, keypad, display etc. Also, the kernel handles all the things that Linux is really good at such as networking and a vast array of device drivers, which take the pain out of interfacing to peripheral hardware.

Libraries

On top of Linux kernel there is a set of libraries including open-source Web browser engine WebKit, well known library libc, SQLite database which is a useful repository for storage and sharing of application data, libraries to play and record audio and video, SSL libraries responsible for Internet security etc.

Android Libraries

This category encompasses those Java-based libraries that are specific to Android development

Android Runtime

This is the third section of the architecture and available on the second layer from the bottom. This section provides a key component called Dalvik Virtual Machine which is a kind of Java Virtual Machine specially designed and optimized for Android.

Application Framework

The Application Framework layer provides many higher-level services to applications in the form of Java classes. Application developers are allowed to make use of these services in their applications.

The Android framework includes the following key services −

• Activity Manager − Controls all aspects of the application lifecycle and activity stack.
• Content Providers − Allows applications to publish and share data with other applications.
• Resource Manager − Provides access to non-code embedded resources such as strings, color settings and user interface layouts.
• Notifications Manager − Allows applications to display alerts and notifications to the user.
• View System − An extensible set of views used to create application user interfaces.

Applications

You will find all the Android application at the top layer. You will write your application to be installed on this layer only. Examples of such applications are Contacts Books, Browser, Games etc

14. Android Layout Types

There are number of Layouts provided by Android which you will use in almost all the Android applications to provide different view, look and feel.

Sr.No	Layout & Description
1	Linear Layout LinearLayout is a view group that aligns all children in a single direction, vertically or horizontally.
2	Relative Layout RelativeLayout is a view group that displays child views in relative positions.
3	Table Layout TableLayout is a view that groups views into rows and columns.
4	Absolute Layout AbsoluteLayout enables you to specify the exact location of its children.
5	Frame Layout The FrameLayout is a placeholder on screen that you can use to display a single view.

 write example programs of any three