Resources Handling in Android:
In Android, we have different types of resources like images, layouts, menus, values.In values, we have strings, colors, dimens, styles.
Before we are using any resources undervalues, we must register those inappropriate XML files.
strings.xml:
In strings.xml, we register all the text resources used through out the application. The syntax for using text resources is as follows.
syntax : <string android:name=”key”>value</string>
For accessing that string in XML and Java, we have different syntaxes here.
XML: @string/key Java: R.string.key
Ex: To register a string ‘Name’ <string android:name=”name_txt”>Name</string>
Accessing in XML: android:text=”@string/name_txt” Accessing in Java: getString(R.string.name_text);
colors.xml:
In colors.xml, we register all the color resources used through out the application. The syntax for using color resources is as follows.
syntax : <color android:name=”key”>value</color>
For accessing that color in XML and Java, we have different syntaxes here.
XML: @color/key Java: R.color.key
Ex: To register a color Black <color android:name=”black”>#000000</color>
Accessing in XML: android:textColor=”@color/black” Accessing in Java: getColor(R.color.black);
Note:
In Android, we use color in hexadecimal RGB firmat
dimens.xml: In Android, we use dimens for providing sizes for Views. The units for this are as follows
sp -> For text size dp -> For all other sizes of views.
Syntax to register dimens: <dimen android:name=”key”>value</dimen>
For accessing that dimen in XML and Java, we have different syntaxes here.
XML: @dimen/key Java: R.dimen.key
Ex: To register a dimen <dimen android:name=”my_text_size”>36sp</dimen> <dimen android:name=”my_view_height”>48dp</dimen>
Accessing in XML: android:layout_height=”@dimen/my_view_height” Accessing in Java: getDimen(R.dimen.my_view_height);
styles.xml:
A style resource defines the format and look for a UI component. It can be applied to an individual view(from layout xml file) or to an entire activity or application(using AndroidManifest.xml).
For defining a style, the syntax is as follows.
<style android:name=”MyFontStyle”> <item android:name=”attributeName1″>value1</item> <item android:name=”attributeName2″>value2</item> | | | </style>
For accessing the above style, the syntax is as follows. in XML: @style/MyFontStyle in Java: R.style.MyFontStyle
Registering string array in resources:
To register string array we use a tag in strings.xml called <string-array>
Ex: <string-array android:name=”array_name”> <item>value1</item> <item>value2</item> <item>value3</item> <item>value4</item> <item>value5</item> </string-array>
To access that array XML – @array/array_name Java – getResources.getStringArray(R.array.array_name)
For more information on styles, refer: https://www.tutorialspoint.com/android/android_styles_and_themes.html
Create an Android application that describes recource handling in Android