Add colorRes and drawableRes API (#98)

* Add API to set the color using its resource

* Add API to set the drawable using its resource

* Add test

* Fix test

recycler-view-divider/src/main/kotlin/com/fondesa/recyclerviewdivider/DividerBuilder.kt

@@ -21,7 +21,10 @@ import android.graphics.drawable.ColorDrawable
 import android.graphics.drawable.Drawable
 import android.util.TypedValue
 import androidx.annotation.ColorInt
+import androidx.annotation.ColorRes
+import androidx.annotation.DrawableRes
 import androidx.annotation.Px
+import androidx.core.content.ContextCompat
 import androidx.recyclerview.widget.GridLayoutManager
 import androidx.recyclerview.widget.LinearLayoutManager
 import androidx.recyclerview.widget.RecyclerView
@@ -112,6 +115,14 @@ class DividerBuilder internal constructor(private val context: Context) {
      */
     fun asSpace(): DividerBuilder = apply { asSpace = true }
 
+    /**
+     * Sets the divider's drawable as a solid color.
+     *
+     * @param colorRes the resource of the color used for each divider.
+     * @return this [DividerBuilder] instance.
+     */
+    fun colorRes(@ColorRes colorRes: Int): DividerBuilder = color(ContextCompat.getColor(context, colorRes))
+
     /**
      * Sets the divider's drawable as a solid color.
      *
@@ -120,6 +131,14 @@ class DividerBuilder internal constructor(private val context: Context) {
      */
     fun color(@ColorInt color: Int): DividerBuilder = drawable(drawable = ColorDrawable(color))
 
+    /**
+     * Sets the divider's drawable.
+     *
+     * @param drawableRes the resource of the [Drawable] used for each divider.
+     * @return this [DividerBuilder] instance.
+     */
+    fun drawableRes(@DrawableRes drawableRes: Int): DividerBuilder = drawable(context.getDrawableCompat(drawableRes))
+
     /**
      * Sets the divider's drawable.
      *
@@ -293,4 +312,7 @@ class DividerBuilder internal constructor(private val context: Context) {
         }
         return transparentDrawable()
     }
+
+    private fun Context.getDrawableCompat(@DrawableRes drawableRes: Int): Drawable = ContextCompat.getDrawable(this, drawableRes)
+        ?: throw NullPointerException("The drawable with resource id $drawableRes can't be loaded. Use the method .drawable() instead.")
 }

recycler-view-divider/src/main/kotlin/com/fondesa/recyclerviewdivider/StaggeredDividerBuilder.kt

@@ -21,7 +21,9 @@ import android.graphics.drawable.ColorDrawable
 import android.graphics.drawable.Drawable
 import android.util.TypedValue
 import androidx.annotation.ColorInt
+import androidx.annotation.ColorRes
 import androidx.annotation.Px
+import androidx.core.content.ContextCompat
 import androidx.recyclerview.widget.RecyclerView
 import androidx.recyclerview.widget.StaggeredGridLayoutManager
 import com.fondesa.recyclerviewdivider.drawable.getThemeDrawable
@@ -82,6 +84,15 @@ class StaggeredDividerBuilder(private val context: Context) {
      */
     fun asSpace(): StaggeredDividerBuilder = apply { asSpace = true }
 
+    /**
+     * Sets the divider's color.
+     * If the color of this divider is not completely opaque (contains some transparency), this builder can't ensure a correct rendering.
+     *
+     * @param colorRes the resource of the color used for each divider.
+     * @return this [StaggeredDividerBuilder] instance.
+     */
+    fun colorRes(@ColorRes colorRes: Int): StaggeredDividerBuilder = color(ContextCompat.getColor(context, colorRes))
+
     /**
      * Sets the divider's color.
      * If the color of this divider is not completely opaque (contains some transparency), this builder can't ensure a correct rendering.

recycler-view-divider/src/test/kotlin/com/fondesa/recyclerviewdivider/DividerBuilderTest.kt

@@ -16,8 +16,15 @@
 
 package com.fondesa.recyclerviewdivider
 
+import android.content.res.Resources
+import android.graphics.Bitmap
+import android.graphics.Canvas
 import android.graphics.Color
+import android.graphics.drawable.BitmapDrawable
 import android.graphics.drawable.ColorDrawable
+import android.graphics.drawable.Drawable
+import android.graphics.drawable.GradientDrawable
+import android.os.Build
 import android.util.TypedValue
 import androidx.annotation.ColorInt
 import androidx.annotation.Px
@@ -41,7 +48,11 @@ import com.fondesa.recyclerviewdivider.tint.TintProvider
 import com.fondesa.recyclerviewdivider.tint.TintProviderImpl
 import com.fondesa.recyclerviewdivider.visibility.VisibilityProvider
 import com.fondesa.recyclerviewdivider.visibility.VisibilityProviderImpl
+import com.nhaarman.mockitokotlin2.any
+import com.nhaarman.mockitokotlin2.anyOrNull
+import com.nhaarman.mockitokotlin2.doReturn
 import com.nhaarman.mockitokotlin2.mock
+import com.nhaarman.mockitokotlin2.spy
 import com.nhaarman.mockitokotlin2.verify
 import com.nhaarman.mockitokotlin2.verifyZeroInteractions
 import org.junit.After
@@ -108,6 +119,22 @@ class DividerBuilderTest {
         verifyZeroInteractions(logger)
     }
 
+    @Test
+    fun `build - colorRes invoked - returns decoration with color`() {
+        scenario = launchThemeActivity(R.style.TestTheme_All)
+
+        val decoration = dividerBuilder()
+            .colorRes(R.color.test_recyclerViewDividerDrawable)
+            .build()
+
+        val provider = (decoration as DividerItemDecoration).drawableProvider
+        assertTrue(provider is DrawableProviderImpl)
+        val providerDrawable = (provider as DrawableProviderImpl).drawable
+        assertTrue(providerDrawable is ColorDrawable)
+        assertEquals(ContextCompat.getColor(context, R.color.test_recyclerViewDividerDrawable), (providerDrawable as ColorDrawable).color)
+        verifyZeroInteractions(logger)
+    }
+
     @Test
     fun `build - color invoked - returns decoration with color`() {
         scenario = launchThemeActivity(R.style.TestTheme_All)
@@ -124,6 +151,38 @@ class DividerBuilderTest {
         verifyZeroInteractions(logger)
     }
 
+    @Test
+    fun `build - drawableRes invoked - returns decoration with drawable`() {
+        scenario = launchThemeActivity(R.style.TestTheme_All)
+        val expectedDrawable = requireNotNull(ContextCompat.getDrawable(context, R.drawable.test_recycler_view_drawable_not_solid))
+
+        val decoration = dividerBuilder()
+            .drawableRes(R.drawable.test_recycler_view_drawable_not_solid)
+            .build()
+
+        val provider = (decoration as DividerItemDecoration).drawableProvider
+        assertTrue(provider is DrawableProviderImpl)
+        val providerDrawable = (provider as DrawableProviderImpl).drawable
+        assertTrue(providerDrawable is GradientDrawable)
+        assertTrue(expectedDrawable.getBitmap().sameAs(providerDrawable.getBitmap()))
+        verifyZeroInteractions(logger)
+    }
+
+    @Test(expected = NullPointerException::class)
+    fun `build - drawableRes invoked with invalid Drawable - throws NullPointerException`() {
+        val resources = mock<Resources> {
+            @Suppress("DEPRECATION")
+            on(it.getDrawable(any())) doReturn null
+            if (Build.VERSION.SDK_INT >= 21) {
+                on(it.getDrawable(any(), anyOrNull())) doReturn null
+            }
+        }
+        val context = spy(context) {
+            on(it.resources) doReturn resources
+        }
+        DividerBuilder(context).drawableRes(R.drawable.test_recycler_view_drawable_not_solid)
+    }
+
     @Test
     fun `build - drawable invoked - returns decoration with drawable`() {
         scenario = launchThemeActivity(R.style.TestTheme_All)
@@ -651,4 +710,16 @@ class DividerBuilderTest {
     } else {
         DividerBuilder(context)
     }
+
+    private fun Drawable.getBitmap(): Bitmap = if (this is BitmapDrawable) {
+        bitmap
+    } else {
+        val width = intrinsicWidth.takeIf { it >= 0 } ?: 1
+        val height = intrinsicHeight.takeIf { it >= 0 } ?: 1
+        val bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888)
+        val canvas = Canvas(bitmap)
+        setBounds(0, 0, canvas.width, canvas.height)
+        draw(canvas)
+        bitmap
+    }
 }

recycler-view-divider/src/test/kotlin/com/fondesa/recyclerviewdivider/StaggeredDividerBuilderTest.kt

@@ -111,6 +111,20 @@ class StaggeredDividerBuilderTest {
         verifyZeroInteractions(logger)
     }
 
+    @Test
+    fun `build - colorRes invoked - returns decoration with color`() {
+        scenario = launchThemeActivity(R.style.TestTheme_All)
+
+        val decoration = staggeredDividerBuilder()
+            .colorRes(R.color.test_recyclerViewDividerDrawable)
+            .build()
+
+        val drawable = (decoration as StaggeredDividerItemDecoration).drawable
+        assertTrue(drawable is ColorDrawable)
+        assertEquals(ContextCompat.getColor(context, R.color.test_recyclerViewDividerDrawable), (drawable as ColorDrawable).color)
+        verifyZeroInteractions(logger)
+    }
+
     @Test
     fun `build - color invoked - returns decoration with color`() {
         scenario = launchThemeActivity(R.style.TestTheme_All)