2. Resources To enable support for different configurations of
the device, an application uses resources in the /res folder of the
project. The folder contains default and alternative resources (for
different configurations). The default resources and all the
alternatives must be identified by the same name. The compiler
creates a /gen folder that creates an enumeration with all the
resources available to the application. The default resources must
always be present because they are loaded at runtime when no other
resource is present. Resources
3. Resources Animator: it contains .xml files with Property
Animations Anim: it contains .xml files with View Animations Color:
it contains .xml files with Color Selector Drawable: it can contain
.png or .xml files Layout: it contains .xml files with layouts
Menu: it contains .xml files with Options menus, Context menus
and/or Sub menus Raw: it contains all other files to recover during
runtime Values: it contains .xml files with values for differnt
configurations. They are: strings, arrays, dimens, colors, styles
Xml: it contains generic .xml files Types
4. Resources You need to create the /res subfolder that specify
the name of the type of configuration that supports to provide
alternative resources to support different configurations: - is the
type of resource that contains as indicated above and identifies
the supported configuration. Ex. res/layout-land contains the
layout to be used when the phone is in landscape mode. You can
specify multiple qualifiers in series. Alternative Resources
5. Resources The most commonly used types of qualifiers are
listed in the same order in which they must be specified in the
name of the /res subfolder: Language (Ex. en, fr, it,...): it
specifies in which language resources are available within the
folder SmallestWidth (swdp Es. sw320dp, sw720dp,...): the resources
of these folders are available only if the terminal has
Min(dp_height, dp_width) >= n Screen Size (small, normal, large,
xlarge): Qualifiers - Typologies
6. Resources ScreenOrientation (port, land) Screen Pixel
Density (ldpi, mdpi, hdpi, xhdpi, xxhdpi, xxxhdpi, tvdpi) ldpi:
120dp mdpi: 160dp hdpi: 240dp xhdpi: 320dp xxhdpi: 480dpi xxxhdpi:
640dp Platform Version (Es. V12, v15, v19, ...): the logic is top
bottom. Ex. A device with V19 verifies the presence of the resource
in v19, then in v18, and so on until it finds one. Qualifiers -
Tipologie
7. Resources The multiple qualifiers must be specified in the
order indicated before: Es. res/drawable-port-hdpi/ The folders
defined with these rules can not contain subfolders The folder
names are case-insensitive It is allowed only one value for each
type of qualifier. Es. res/drawable/it-en INCORRECT If you want to
provide the same resource configuration for it and en, you have to
create 2 folders and enter the same resource in both
res/drawable-it CORRECT res/drawable-en CORRECT Qualifiers -
Rules
8. Resources When you insert a new resource in the project, the
aapt automatically generates the R class that contains all the IDs
of resources on the basis of fundamental subdirectory in which you
can retrieve them at runtime: R.anim. R.array. R.bool. R.color.
R.dimen. R.drawable. R.integer. R.layout. R.menu. R.raw. R.string.
R.style. Resource access at runtime
9. Resources The R class is generated for each project and it
is created in the package defined in the manifest: [.]R.. is
optional if the class is imported into the R class is the same from
which you want to retrieve a resource. In this way it is possible
to access resources outside projects and imported to the system
resources of Android for which = android Then the developer may
require a system resource with the expression: android.R.. N.B.:
system resources at runtime are taken from the firmware of the
terminal, so the same ID can refer to different resources in
terminals with different firmware. Resource access at runtime
10. Resources To access resources from an xml file using the
following syntax: @[:]/ is optional if you want to use a resource
package of the project. Pattern: during the creation of the layout
you should always include references to external resources instead
of entering the value in the layout. Es.
android:text="@string/hello" CORRECT android:text="Hello!" CORRECT
BUT NOT RECOMMENDED Resource access from an xml file
11. Resources Layout
12. Resources text_string String
13. Resources View Animation
14. Resources Property Animation
15. Resources Menu
16. Resources Style
17. Resources Drawable Selector
18. Resources Shape
19. Resources [true |
false]hex_colordimensionintegerintegerresource Other Resources
