Android Tutorials

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ANDROID TUTORIALS BUILD YOUR FIRST APP

• Smartphones. They can easily be called the most
  insaely popular and fastly growing invention of
  the 21st century. Nearly 2 billion people across
  the globe use smartphones. Smartphones run on
  various Operating systems, and one of the most
  widely used is 'ANDROID'. The Android Operating
  system was created and developed by global search
  engine company Google. Easy to use, quick to
  respond, Android is very widely used. It runs on
  'App'. An Android App or Android Application, is
  a mobile application designed to run on Android
  devices. The uses for Android apps range from
  music to science, from games to photography, from
  religion to dictionary, from Maths to History.
  There's an app for almost everything- you name
  it. According to stats, there are more than 2.8
  million android apps available in market. And in
  this Android Tutorial, we will teach you how to
  make your own first android app.

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This Android Tutorial is meant to only teach you
the basics of Android app development. There are
many android tutorials available online, and
offline, which go in to much more depth, but if
you are a beginner,
then this Android Tutorial is perfect for you. By
the end of this Android Tutorial, you will have
learned how to make a simple android application
using App Studio. Most of the Android Tutorials
available online teach you on App Studio, as it
is very easy to use. The first and foremost step
in this Android Tutorial is, Install App Studio,
if you do not have it already. To make this
android tutorial easier for you to understand, we
have discussed the process into four major parts-
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1. WRITING A NEW PROJECT
The first step to create your own android app in
this Android Tutorial, is to create a new project
in the App Studio. To ensure that you learn from
this Android Tutorial, follow each and every step
given below carefully.
Step 1. Create a new project in Android Studio.
In the welcome window of the App, click on file,
and then Click on 'New Project'.
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Step 2. After completing Step 1 successfully, you
will move to the New Project screen. In new
project screen, enter the following Application
name "AppOne." Company Domain
"xyzdemo.com" Then in the location option, choose
any location you want to save your project in,
and then Click 'Next'. Step 3. After this you
will be followed into the Targeted Android
devices screen. Since this Android Tutorial is
for basic level, you should keep the options as
default and Click 'Next'. You will learn more
about the SDK versions in advanced android
tutorials later. Step 4. In this step you will
enter the 'Add an Activity to Mobile' screen.
Select "Empty Activity" and then click on the
Next button. Step 5. Then you will see the
'Customize the Activity' window. Here, in this
window, do not change the default values and
click on the Finish bottom. After processing,
Android Studio will open the IDE. Make sure you
check the important files once again thoroughly.
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Make sure the Project screen is appearing (click
on View, then on Tool Windows, and them
onProject) and the Android view is selected from
the drop-down list at the top of that window. You
will then see the following App gt java gt
com.xyzdemo.apponegt MainActivity.java This is the
main activity window, the official beginning of
your App. When you will have built your App and
run it, the system will launch a demo if this
activity. App gt res gt layout gt activity_main.xml
This XML file defines the layout for the
activity's User Interface. It contains a text
View element with the text "This is my First
App!".app gt manifests gt AndroidManifest.xml. The
manifest file will define and describe the app's
components. Gradle Scripts gt build.gradle You'll
see two files with this name one for the project
and one for the "app" module.
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2. RUNNING YOUR APP ON A REAL ANDROID DEVICE FOR
THE FIRST TIME. In the first major step of this
Android tutorial we taught you how to develop an
App that will say "This is my first Android
App!". Now to run this small basic app on an
actual android device, carefully read the
following steps, and execute them without any
mistakes Step 1. Connect your android device to
your development machine with a USB cable. Step
2. Enable USB debugging on the android device you
are using by going to Settings gt Developer
options. Now you can run the app using Android
Studio as follows 1. In App Studio, click the
app module in the project window and then select
run gt Run (or click run in the toolbar). 2. In
the Select Deployment Target screen, select your
device, and then click on 'OK'. Android Studio
will then install your newly made app on your
connected android device and then it will run
it. You'll see "This is my First Android App!" On
your connected Android Device!
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3. BUILDING A USER INTERFACE FOR YOUR APP. In
this part of your Android Tutorial to build your
first App you will learn to build an interface
for your app. In the first two parts, you learned
to command, and Run, and now it's time to adda an
interface and change your App's look! Stay tuned
to the android tutorial and follow the below
procedure to learn the basics of UI development
for Android Applications. Since this Android
Tutorial is a basic one, we will teach you how to
add a text box, and how to add a button. In this
lesson, you'll use the Android Studio Layout
Editor to create a layout that includes a text
box and a button. The user interface for an
Android app is built using a hierarchy of layouts
(View Group objects) and widgets (View objects).
Layouts are invisible containers that control how
its child views are positioned on the screen. UI
components like buttons and text boxes are
widgets. Illustration of how View group objects
form branches in the layout and contain View
objects android provides an XML vocabulary for
View group and View classes, so most of your UI
is defined in XML files. However, instead of
teaching you to write some XML, this lesson shows
you how to create a layout using Android Studio's
Layout Editor, which makes it easy to build a
layout by drag-and-dropping views. Open the
Layout Editor Note This lesson expects you are
using Android Studio 2.3 or higher and you've
followed the previous lesson to create your
Android project. To get started, set up your
workspace as follows
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1. In Android Studio's Project screen, click on
the following, open app gt res gt layout gt
activity_main.xml. 2. To make more room for the
Layout Editor, hide the project window by
selecting View gt Tool Windows gt Project (or click
Projection the left side of Android Studio). 3.
If your editor shows the XML source, click the
design tab at the bottom of the window. 4. Click
Show Blueprint so only the blueprint layout is
visible. 5. Make sure Show Constraints is on. The
tooltip in the toolbar should read hide
Constraints (because they're now showing). 6.
Make sure Auto connect is off. The tooltip in the
toolbar should read Turn On Auto connect(because
it's now off). 7. Click Default Margins in the
toolbar and select 16(you can still adjust the
margin for each view later). 8. Click Device in
Editor in the toolbar and select Pixel XL
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9. The Layout Editor showing activity_main.xml
The Component Tree window on the bottom-left side
shows the layout's hierarchy of views. In this
case, the root view is a Constraint Layout,
containing just one Text View object. Constraint
Layout is a layout that defines the position for
each view based on constraints to sibling views
and the parent layout. In this way, you can
create both simple and complex layouts with a
flat view hierarchy.
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That is, it avoids the need for nested layouts),
which can increase the time required to draw the
UI. Illustration of two views positioned inside
Constraint Layout for example, you can declare
the following layout (in figure 4) .View A
appears 16dp from the top of the parent
layout..View A appears 16dp from the left of the
parent layout..View B appears 16dp to the right
of view A..View B is aligned to the top of view
A. In the following sections, you'll build a
layout similar to this. Add a text box. The text
box is constrained to the top and left of the
parent layout

1. First, you need to remove what's already in the
   layout. So click Text View in the Component Tree
   window, and then press Delete.
2. From the Palette window on the left, click Text
   in the left pane, and then drag Plain Text into
   the design editor and drop it near the top of the
   layout. This is an Edit Text Widget that accepts
   plain text input.
3. Click the view in the design editor. You can now
   see the resizing handles on each corner
   (squares), and the constraint anchors on each
   side (circles).For better control, you might want
   to zoom in on the editor to 75 or higher using
   the buttons in the toolbar.
4. Click-and-hold the anchor on the top side, and
   then drag it up until it snaps to the top of the
   layout and release. That's a constraintit
   specifies the view should be 16dp from the top of
   the layout (because you set the default margins
   to 16dp).

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5. Similarly, create a constraint from the left
side of the view to the left side of the
layout Add a button. The button is constrained to
the right side of the text box and its
baseline 1. From the palettes window, click
widgets in the left pane, and then drag Button
into the design editor and drop it near the right
side. 2. Create a constraint from the left side
of the button to the right side of the text
box. 3. To constrain the views in a horizontal
alignment, you need to create a constraint
between the text baselines. So click the button,
and then click baseline Constraint, which appears
in the design editor directly below the selected
view. The baseline anchor appears inside the
button. Click-and-hold on this anchor and then
drag it to the baseline anchor that appears in
the text box. You can also create a horizontal
alignment using the top or bottom edges, but the
button includes padding around its image, so the
visual alignment is wrong if you align these
views that way.
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4. YOU ARE AN APP DEVELOPER NOW!
This Android Tutorial was a basic one, and now
you have an android application that displays
"This is my first Android App!" And also has a
text box and a button! As you will take more
android tutorials, you will get more involved
into android app development and learn more about
it. (For example, the buttons and text box have
not been assigned any activity yet, but you can
develop them to make them do anything you want!)
And now, finally, this Android Tutorial has come
to an end, and you can proudly say that you are
the developer of an Android App! Now go ahead,
take many more android tutorials, practice a lot,
and soon you might be programming the next big
APP of the world! Happy programming!!!
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