Lesson 3: Editing XML, and Viewing
it in the Graphical Layout
INTRODUCTION
In this lesson you
will develop good habits as a beginning programmer by testing what each piece
of code does, and seeing and experimenting with how it works. Through a trial-and-error
approach, you will understand how to change certain parts of the code to see
how it comes out in the Graphic Layout of Eclipse. You will also learn how to
clean a Java project of errors and debug it as well.
LESSON
OBJECTIVES
By the end of this lesson, you will be able to:
Section #1: Establishing
Good Programming Habits
1.
Review
expert tips, tools and suggestions to develop your programming skills
2.
Describe
the benefits of “cleaning” a Java For Android Project
Section #2: Describe
the changes that happen when you edit the XML
1.
Identify
the components of the XML and how it works with the Java language to define
views.
2.
Determine
how to manipulate XML to produce desired results.
Section #3: Understanding
the Importance of the GUI
1.
Describe the
benefits of using a graphic user interface (GUI) in the development process.
Section #4: Video Demonstration of How
to Clean Your Project
1.
Learning
how to 'Clean' your project
2.
How to
change code in the XML
3.
How to
view changes in Graphical Layout
LEARNING SEQUENCE
Required Reading
|
Read the following:
·
Section
#1:
·
Section
#2:
· Section
#3:
|
Resources
|
View the
following:
·
Video Transcripts
|
Assignments
|
Complete the
following:
·
What Do Beginning
Programmers Need to Know about Android?
·
What’s in a GUI?
|
INSTRUCTION
Section #1: Establishing Good Programming Habits
In this section, you will develop an
understanding of what it is like to work as an Android developer and
programmer.
Step 1.
In this interview
with Tony Hillerson, an Android developer at Effective UI, you will read about the
skills and tools you’ll need to become an Android developer. Hillerson also
discusses a variety of topics related to programming for Android with Java, including
understanding how Android's XML-defined views translate onto the screen.
Information about the mobile marketplace is also discussed.
Step 2.
This article presents
useful information you can use to better understand the power of Eclipse with
Android plugin. You will also review information presented on the many editors
Eclipse uses and understand how to best configure them. The topic of version
control is also touched upon at the end of this tip sheet.
Step 3.
In this short
tutorial you will be provided an overview of the process of “cleaning” an
Android project in the Eclipse IDE. This will be beneficial as you begin the
development process. In the process of Android programming you will need to be
able to “clean” your project and also check for errors in development.
Step 4.
Complete
Assignment #1: What Do
Beginning Programmers Need to Know about Android?
Section #2: Describe the changes
that happen when you edit the XML
In this section you will be introduced
to XML layouts and the options for using them in the development of a layout
for an Android application.
Step 1.
In this resource you
are introduced to the user interface components of Android through the process
of editing the XML code for the layout. On this web page view the area titled Write The XML. In this area you are
provided a section of sample code for the layout described. Review this page
and read the areas titled Load The XML
Resource, Attributes, ID and Layout Parameters. These sections will provide you with an overview
of the components of the XML and how it works with the Java language to define
the views.
Section #3: Understanding the
Importance of the GUI
An
important part of most applications is the Graphical User Interface, or GUI. In
this section you will explore how to use the Graphical Layout Editor to develop
your Android application.
Step 1.
This reading will
assist you in describing the benefits of using a graphic user interface (GUI)
in the development process. You will review all of the main features of the
editor including the canvas, outline, palette and configuration chooser.
Viewing video segments provided in links in the reading will allow you to see
how these features work.
Step 2.
Complete Assignment #2: What’s
in a GUI?
Section #4: Video
Demonstration of How to Clean Your Project
Cleaning your project
is when Eclipse scans your app of any false errors, and cleans it. This video
demonstration will walk you through the process of how to clean your project. This
is an important step that programmers must use throughout the development
process to make certain that there are no errors in their code and that their
applications run seamlessly. You will also practice how to change code in the
XML and then learn how to view changes in Graphical Layout. Please pause and
review the video, as necessary, to complete tasks. Transcripts are provided.
Step 1.
SUMMARY
In this lesson you
gained exposure to XML and experimented and tested various changes to your
code. You also used Eclipse to clean your project and to identify any potential
errors, a necessary step and best practice for all programmers. Through
demonstration, trial and error with XML and your code, you explored various
graphical layout options with manipulations to the code. In the next lesson you
will expand on your knowledge of the Java language as you work more in-depth
with the Eclipse IDE.
ASSIGNMENTS
· What Do Beginning Programmers Need to Know about Android?
· What’s in a GUI?
