@Test public void testDarker() {

	// Arrange:
	final int color = Color.parseColor("#FFF44336");
	// Act + Assert:
	assertThat(Colors.darker(color, 0f), is(color));
	float fraction = 0.01f;
	while (fraction < 1.0f) {
		final int darkerColor = Colors.darker(color, fraction);
		assertThat(darkerColor, lessThan(color));
		assertThat(Color.alpha(darkerColor), is(Color.alpha(color)));
		fraction += 0.01f;
	}
}