page.title=Working with Drawables @jd:body

This lesson teaches you to

  1. Tint Drawable Resources
  2. Extract Prominent Colors from an Image
  3. Create Vector Drawables

You should also read

The following capabilities for drawables help you implement material design in your apps:

This lesson shows you how to use these features in your app.

Tint Drawable Resources

With Android 5.0 (API level 21) and above, you can tint bitmaps and nine-patches defined as alpha masks. You can tint them with color resources or theme attributes that resolve to color resources (for example, ?android:attr/colorPrimary). Usually, you create these assets only once and color them automatically to match your theme.

You can apply a tint to {@link android.graphics.drawable.BitmapDrawable} or {@link android.graphics.drawable.NinePatchDrawable} objects with the {@code setTint()} method. You can also set the tint color and mode in your layouts with the android:tint and android:tintMode attributes.

Extract Prominent Colors from an Image

The Android Support Library r21 and above includes the {@link android.support.v7.graphics.Palette} class, which lets you extract prominent colors from an image. This class extracts the following prominent colors:

To extract these colors, pass a {@link android.graphics.Bitmap} object to the {@link android.support.v7.graphics.Palette#generate Palette.generate()} static method in the background thread where you load your images. If you can't use that thread, call the {@link android.support.v7.graphics.Palette#generateAsync Palette.generateAsync()} method and provide a listener instead.

You can retrieve the prominent colors from the image using the getter methods in the Palette class, such as Palette.getVibrantColor.

To use the {@link android.support.v7.graphics.Palette} class in your project, add the following Gradle dependency to your app's module:

dependencies {
    ...
    compile 'com.android.support:palette-v7:21.0.0'
}

For more information, see the API reference for the {@link android.support.v7.graphics.Palette} class.

Create Vector Drawables

Video

Android Vector Graphics

In Android 5.0 (API Level 21) and above, you can define vector drawables, which scale without losing definition. You need only one asset file for a vector image, as opposed to an asset file for each screen density in the case of bitmap images. To create a vector image, you define the details of the shape inside a <vector> XML element.

The following example defines a vector image with the shape of a heart:

<!-- res/drawable/heart.xml -->
<vector xmlns:android="http://schemas.android.com/apk/res/android"
    <!-- intrinsic size of the drawable -->
    android:height="256dp"
    android:width="256dp"
    <!-- size of the virtual canvas -->
    android:viewportWidth="32"
    android:viewportHeight="32">

  <!-- draw a path -->
  <path android:fillColor="#8fff"
      android:pathData="M20.5,9.5
                        c-1.955,0,-3.83,1.268,-4.5,3
                        c-0.67,-1.732,-2.547,-3,-4.5,-3
                        C8.957,9.5,7,11.432,7,14
                        c0,3.53,3.793,6.257,9,11.5
                        c5.207,-5.242,9,-7.97,9,-11.5
                        C25,11.432,23.043,9.5,20.5,9.5z" />
</vector>

Vector images are represented in Android as {@link android.graphics.drawable.VectorDrawable} objects. For more information about the pathData syntax, see the SVG Path reference. For more information about animating the properties of vector drawables, see Animating Vector Drawables.