[android] - range alpha between 0 and 1 with android color conversion

platform/android/MapboxGLAndroidSDK/build.gradle

@@ -124,6 +124,7 @@ android {
     testOptions {
         unitTests {
             returnDefaultValues true
+            includeAndroidResources = true
         }
     }
 

platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/style/expressions/Expression.java

@@ -213,7 +213,7 @@ public static Expression literal(@NonNull Object[] array) {
    * @return the color expression
    */
   public static Expression color(@ColorInt int color) {
-    int[] rgba = PropertyFactory.colorToRgbaArray(color);
+    float[] rgba = PropertyFactory.colorToRgbaArray(color);
     return rgba(rgba[0], rgba[1], rgba[2], rgba[3]);
   }
 

platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/style/layers/PropertyFactory.java

@@ -6,6 +6,7 @@
 
 import com.mapbox.mapboxsdk.style.expressions.Expression;
 
+import java.text.DecimalFormat;
 import java.util.Locale;
 
 /**
@@ -2397,22 +2398,29 @@ public static PropertyValue<Expression> textOptional(Expression value) {
 
   /**
    * Converts Android color int to "rbga(r, g, b, a)" String equivalent.
+   * <p>
+   * Alpha value will be converted from 0-255 range to 0-1.
+   * </p>
    *
    * @param color Android color int
    * @return String rgba color
    */
   public static String colorToRgbaString(@ColorInt int color) {
-    return String.format(Locale.US, "rgba(%d, %d, %d, %d)",
-      (color >> 16) & 0xFF, (color >> 8) & 0xFF, color & 0xFF, (color >> 24) & 0xFF);
+    String alpha = new DecimalFormat("#.###").format(((float)((color >> 24) & 0xFF)) / 255.0f);
+    return String.format(Locale.US, "rgba(%d, %d, %d, %s)",
+      (color >> 16) & 0xFF, (color >> 8) & 0xFF, color & 0xFF, alpha);
   }
 
   /**
-   * Converts Android color int to rgba int array.
+   * Converts Android color int to rgba float array.
+   * <p>
+   * Alpha value will be converted from 0-255 range to 0-1.
+   * </p>
    *
    * @param color Android color int
    * @return int rgba array
    */
-  public static int[] colorToRgbaArray(@ColorInt int color) {
-    return new int[] {(color >> 16) & 0xFF, (color >> 8) & 0xFF, color & 0xFF, (color >> 24) & 0xFF};
+  public static float[] colorToRgbaArray(@ColorInt int color) {
+    return new float[] {(color >> 16) & 0xFF, (color >> 8) & 0xFF, color & 0xFF, ((color >> 24) & 0xFF) / 255.0f};
   }
-}
+}

platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/style/layers/property_factory.java.ejs

@@ -10,6 +10,7 @@ import android.support.annotation.ColorInt;
 
 import com.mapbox.mapboxsdk.style.expressions.Expression;
 
+import java.text.DecimalFormat;
 import java.util.Locale;
 
 /**
@@ -87,22 +88,29 @@ public class PropertyFactory {
 <% } -%>
   /**
    * Converts Android color int to "rbga(r, g, b, a)" String equivalent.
+   * <p>
+   * Alpha value will be converted from 0-255 range to 0-1.
+   * </p>
    *
    * @param color Android color int
    * @return String rgba color
    */
   public static String colorToRgbaString(@ColorInt int color) {
-    return String.format(Locale.US, "rgba(%d, %d, %d, %d)",
-      (color >> 16) & 0xFF, (color >> 8) & 0xFF, color & 0xFF, (color >> 24) & 0xFF);
+    String alpha = new DecimalFormat("#.###").format(((float)((color >> 24) & 0xFF)) / 255.0f);
+    return String.format(Locale.US, "rgba(%d, %d, %d, %s)",
+      (color >> 16) & 0xFF, (color >> 8) & 0xFF, color & 0xFF, alpha);
   }
 
   /**
-   * Converts Android color int to rgba int array.
+   * Converts Android color int to rgba float array.
+   * <p>
+   * Alpha value will be converted from 0-255 range to 0-1.
+   * </p>
    *
    * @param color Android color int
    * @return int rgba array
    */
-  public static int[] colorToRgbaArray(@ColorInt int color) {
-    return new int[] {(color >> 16) & 0xFF, (color >> 8) & 0xFF, color & 0xFF, (color >> 24) & 0xFF};
+  public static float[] colorToRgbaArray(@ColorInt int color) {
+    return new float[] {(color >> 16) & 0xFF, (color >> 8) & 0xFF, color & 0xFF, ((color >> 24) & 0xFF) / 255.0f};
   }
-}
+}

platform/android/MapboxGLAndroidSDK/src/test/java/com/mapbox/mapboxsdk/style/expressions/ExpressionTest.java

@@ -3,6 +3,8 @@
 import android.graphics.Color;
 import com.mapbox.mapboxsdk.style.layers.PropertyFactory;
 import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.robolectric.RobolectricTestRunner;
 
 import java.util.Arrays;
 
@@ -85,6 +87,7 @@
 /**
  * Expression unit tests that validate the expression output with the expected Object[]array representation.
  */
+@RunWith(RobolectricTestRunner.class)
 public class ExpressionTest {
 
   @Test
@@ -117,7 +120,7 @@ public void testRgbaLiteral() throws Exception {
 
   @Test
   public void testToRgba() throws Exception {
-    Object[] expected = new Object[] {"to-rgba", new Object[] {"to-color", "rgba(255, 0, 0, 255)"}};
+    Object[] expected = new Object[] {"to-rgba", new Object[] {"to-color", "rgba(255, 0, 0, 1)"}};
     Object[] actual = toRgba(toColor(literal(PropertyFactory.colorToRgbaString(Color.RED)))).toArray();
     assertTrue("expression should match", Arrays.deepEquals(expected, actual));
   }
@@ -138,7 +141,7 @@ public void testEqLiteral() throws Exception {
 
   @Test
   public void testEqExpression() throws Exception {
-    Object[] expected = new Object[] {"==",new Object[]{"get", "hello"}, 1f};
+    Object[] expected = new Object[] {"==", new Object[] {"get", "hello"}, 1f};
     Object[] actual = eq(get("hello"), 1).toArray();
     assertTrue("expression should match", Arrays.deepEquals(expected, actual));
   }
@@ -159,7 +162,7 @@ public void testNeqLiteral() throws Exception {
 
   @Test
   public void testNeqExpression() throws Exception {
-    Object[] expected = new Object[] {"!=",new Object[]{"get", "hello"}, 1f};
+    Object[] expected = new Object[] {"!=", new Object[] {"get", "hello"}, 1f};
     Object[] actual = neq(get("hello"), 1).toArray();
     assertTrue("expression should match", Arrays.deepEquals(expected, actual));
   }
@@ -1140,7 +1143,7 @@ public void testLiteralPrimitiveArrayConversion() throws Exception {
   @Test
   public void testColorConversion() {
     Expression greenColor = color(0xFF00FF00);
-    Object[] expected = new Object[] {"rgba", 0f, 255f, 0f, 255f};
+    Object[] expected = new Object[] {"rgba", 0f, 255f, 0f, 1f};
     assertTrue("expression should match", Arrays.deepEquals(expected, greenColor.toArray()));
   }
 
@@ -1250,7 +1253,7 @@ public void testRawAndroidColors() {
   public void testRawRgbaColor() {
     Expression expected = interpolate(
       exponential(2f), zoom(),
-      literal(5f), literal("rgba(0, 0, 0, 255)"),
+      literal(5f), literal("rgba(0, 0, 0, 1)"),
       literal(10.5f), literal("rgb(255, 0, 0)"),
       literal(15), color(Color.GREEN),
       literal(20), literal(PropertyFactory.colorToRgbaString(Color.BLUE)));
@@ -1272,4 +1275,19 @@ public void testRawMatchNumbers() {
       stop("layer2", 2.7));
     assertEquals("expressions should match", expected, raw(expected.toString()));
   }
+
+  @Test
+  public void testAlphaValueInColorConversion() {
+    // regression test for #12198
+    Expression colorExpression = color(Color.parseColor("#41FF0000")); // 25.4% alpha red
+    Object[] result = colorExpression.toArray();
+    assertEquals("alpha value should match", 0.254f, (Float) result[4], 0.001f);
+  }
+
+  @Test
+  public void testAlphaValueInStringConversion() {
+    String color = PropertyFactory.colorToRgbaString(Color.parseColor("#41FF0000")).split(" ")[3];
+    String alpha = color.substring(0, color.length() - 1);
+    assertEquals("alpha value should match", 0.254f, Float.valueOf(alpha), 0.001f);
+  }
 }