This page defines more types of resources you can externalize, including:
TypedArray
(which you can use
for an array of drawables).A boolean value defined in XML.
Note: A bool is a simple resource that is referenced
using the value provided in the name
attribute (not the name of the XML file). As
such, you can combine bool resources with other simple resources in the one XML file,
under one <resources>
element.
res/values/filename.xml
<bool>
element's name
will be used as the resource
ID.R.bool.bool_name
@[package:]bool/bool_name
<?xml version="1.0" encoding="utf-8"?> <resources> <bool name="bool_name" >[true | false]</bool> </resources>
res/values-small/bools.xml
:
<?xml version="1.0" encoding="utf-8"?> <resources> <bool name="screen_small">true</bool> <bool name="adjust_view_bounds">true</bool> </resources>
This application code retrieves the boolean:
Resources res =getResources()
; boolean screenIsSmall = res.getBoolean
(R.bool.screen_small);
This layout XML uses the boolean for an attribute:
<ImageView android:layout_height="fill_parent" android:layout_width="fill_parent" android:src="@drawable/logo" android:adjustViewBounds="@bool/adjust_view_bounds" />
A color value defined in XML.
The color is specified with an RGB value and alpha channel. You can use a color resource
any place that accepts a hexadecimal color value. You can also use a color resource when a
drawable resource is expected in XML (for example, android:drawable="@color/green"
).
The value always begins with a pound (#) character and then followed by the Alpha-Red-Green-Blue information in one of the following formats:
Note: A color is a simple resource that is referenced
using the value provided in the name
attribute (not the name of the XML file). As
such, you can combine color resources with other simple resources in the one XML file,
under one <resources>
element.
res/values/colors.xml
<color>
element's name
will be used as the
resource ID.R.color.color_name
@[package:]color/color_name
<?xml version="1.0" encoding="utf-8"?> <resources> <color name="color_name" >hex_color</color> </resources>
res/values/colors.xml
:
<?xml version="1.0" encoding="utf-8"?> <resources> <color name="opaque_red">#f00</color> <color name="translucent_red">#80ff0000</color> </resources>
This application code retrieves the color resource:
Resources res =getResources()
; int color = res.getColor
(R.color.opaque_red);
This layout XML applies the color to an attribute:
<TextView android:layout_width="fill_parent" android:layout_height="wrap_content" android:textColor="@color/translucent_red" android:text="Hello"/>
A dimension value defined in XML. A dimension is specified with a number followed by a unit of measure. For example: 10px, 2in, 5sp. The following units of measure are supported by Android:
dp
160dp
is
always one inch regardless of the screen density. The ratio of dp-to-pixel will change with the
screen density, but not necessarily in direct proportion. You should use these units when specifying
view dimensions in your layout, so the UI properly scales to render at the same actual size on
different screens. (The compiler accepts both "dip" and "dp", though "dp" is more consistent with
"sp".)sp
pt
px
mm
in
Note: A dimension is a simple resource that is referenced
using the value provided in the name
attribute (not the name of the XML file). As
such, you can combine dimension resources with other simple resources in the one XML file,
under one <resources>
element.
res/values/filename.xml
<dimen>
element's name
will be used as the
resource ID.R.dimen.dimension_name
@[package:]dimen/dimension_name
<?xml version="1.0" encoding="utf-8"?> <resources> <dimen name="dimension_name" >dimension</dimen> </resources>
res/values/dimens.xml
:
<?xml version="1.0" encoding="utf-8"?> <resources> <dimen name="textview_height">25dp</dimen> <dimen name="textview_width">150dp</dimen> <dimen name="ball_radius">30dp</dimen> <dimen name="font_size">16sp</dimen> </resources>
This application code retrieves a dimension:
Resources res =getResources()
; float fontSize = res.getDimension
(R.dimen.font_size);
This layout XML applies dimensions to attributes:
<TextView android:layout_height="@dimen/textview_height" android:layout_width="@dimen/textview_width" android:textSize="@dimen/font_size"/>
A unique resource ID defined in XML. Using the name you provide in the <item>
element, the Android developer tools create a unique integer in your project's R.java
class, which you can use as an
identifier for an application resources (for example, a View
in your UI layout)
or a unique integer for use in your application code (for example, as an ID for a dialog or a
result code).
Note: An ID is a simple resource that is referenced
using the value provided in the name
attribute (not the name of the XML file). As
such, you can combine ID resources with other simple resources in the one XML file,
under one <resources>
element. Also, remember that an ID resources does not reference
an actual resource item; it is simply a unique ID that you can attach to other resources or use
as a unique integer in your application.
res/values/filename.xml
R.id.name
@[package:]id/name
<?xml version="1.0" encoding="utf-8"?> <resources> <item type="id" name="id_name" /> </resources>
XML file saved at res/values/ids.xml
:
<?xml version="1.0" encoding="utf-8"?> <resources> <item type="id" name="button_ok" /> <item type="id" name="dialog_exit" /> </resources>
Then, this layout snippet uses the "button_ok" ID for a Button widget:
<Button android:id="@id/button_ok" style="@style/button_style" />
Notice that the android:id
value does not include the plus sign in the ID reference,
because the ID already exists, as defined in the ids.xml
example above. (When you specify an
ID to an XML resource using the plus sign—in the format android:id="@+id/name"
—it means that the "name" ID does not exist and should be created.)
As another example, the following code snippet uses the "dialog_exit" ID as a unique identifier for a dialog:
showDialog
(R.id.dialog_exit);
In the same application, the "dialog_exit" ID is compared when creating a dialog:
protected Dialog onCreateDialog(int)
(int id) {
Dialog dialog;
switch(id) {
case R.id.dialog_exit:
...
break;
default:
dialog = null;
}
return dialog;
}
An integer defined in XML.
Note: An integer is a simple resource that is referenced
using the value provided in the name
attribute (not the name of the XML file). As
such, you can combine integer resources with other simple resources in the one XML file,
under one <resources>
element.
res/values/filename.xml
<integer>
element's name
will be used as the
resource ID.R.integer.integer_name
@[package:]integer/integer_name
<?xml version="1.0" encoding="utf-8"?> <resources> <integer name="integer_name" >integer</integer> </resources>
XML file saved at res/values/integers.xml
:
<?xml version="1.0" encoding="utf-8"?> <resources> <integer name="max_speed">75</integer> <integer name="min_speed">5</integer> </resources>
This application code retrieves an integer:
Resources res =getResources()
; int maxSpeed = res.getInteger
(R.integer.max_speed);
An array of integers defined in XML.
Note: An integer array is a simple resource that is referenced
using the value provided in the name
attribute (not the name of the XML file). As
such, you can combine integer array resources with other simple resources in the one XML file,
under one <resources>
element.
res/values/filename.xml
<integer-array>
element's name
will be used as the
resource ID.R.array.string_array_name
@[package:]array.integer_array_name
<?xml version="1.0" encoding="utf-8"?> <resources> <integer-array name="integer_array_name"> <item >integer</item> </integer-array> </resources>
res/values/integers.xml
:
<?xml version="1.0" encoding="utf-8"?> <resources> <integer-array name="bits"> <item>4</item> <item>8</item> <item>16</item> <item>32</item> </integer-array> </resources>
This application code retrieves the integer array:
Resources res =getResources()
; int[] bits = res.getIntArray
(R.array.bits);
A TypedArray
defined in XML. You can use
this to create an array of other resources, such as drawables. Note that the array
is not required to be homogeneous, so you can create an array of mixed resource types, but
you must be aware of what and where the data types are in the array so that you can properly obtain
each item with the TypedArray
's get...()
methods.
Note: A typed array is a simple resource that is referenced
using the value provided in the name
attribute (not the name of the XML file). As
such, you can combine typed array resources with other simple resources in the one XML file,
under one <resources>
element.
res/values/filename.xml
<array>
element's name
will be used as the
resource ID.TypedArray
.R.array.array_name
@[package:]array.array_name
<?xml version="1.0" encoding="utf-8"?> <resources> <array name="integer_array_name"> <item>resource</item> </array> </resources>
res/values/arrays.xml
:
<?xml version="1.0" encoding="utf-8"?> <resources> <array name="icons"> <item>@drawable/home</item> <item>@drawable/settings</item> <item>@drawable/logout</item> </array> <array name="colors"> <item>#FFFF0000</item> <item>#FF00FF00</item> <item>#FF0000FF</item> </array> </resources>
This application code retrieves each array and then obtains the first entry in each array:
Resources res =getResources()
; TypedArray icons = res.obtainTypedArray
(R.array.icons); Drawable drawable = icons.getDrawable
(0); TypedArray colors = res.obtainTypedArray
(R.array.icons); int color = colors.getColor
(0,0);