Handle color selector in DeferredColor.resolve (#32)

* Improve attribute resolution error messages
* Add KDoc warnings about attribute color selectors

deferred-resources/src/androidTest/java/com/backbase/deferredresources/DeferredColorTest.kt

@@ -1,44 +1,73 @@
 package com.backbase.deferredresources
 
 import android.graphics.Color
+import androidx.test.filters.SdkSuppress
 import com.backbase.deferredresources.test.R
 import com.google.common.truth.Truth.assertThat
 import org.junit.Test
 
 class DeferredColorTest {
 
- @Test fun constant_withIntValue_returnsSameValue() {
+ //region Constant
+ @Test fun constantResolve_withIntValue_returnsSameValue() {
  val deferred = DeferredColor.Constant(Color.MAGENTA)
  assertThat(deferred.resolve(context)).isEqualTo(Color.MAGENTA)
  }
 
- @Test fun constant_withStringValue_returnsParsedValue() {
+ @Test fun constantResolve_withStringValue_returnsParsedValue() {
  val deferred = DeferredColor.Constant("#00FF00")
  assertThat(deferred.resolve(context)).isEqualTo(Color.GREEN)
  }
+ //endregion
 
- @Test fun resource_resolvesWithContext() {
+ //region Resource
+ @Test fun resourceResolve_withStandardColor_resolvesColor() {
  val deferred = DeferredColor.Resource(R.color.blue)
  assertThat(deferred.resolve(context)).isEqualTo(Color.BLUE)
  }
 
- @Test fun attribute_resolvesWithContext() {
+ @Test fun resourceResolve_withSelectorColor_resolvesDefaultColor() {
+ val deferred = DeferredColor.Resource(R.color.stateful_color_without_attr)
+ assertThat(deferred.resolve(AppCompatContext())).isEqualTo(Color.parseColor("#aaaaaa"))
+ }
+
+ @SdkSuppress(minSdkVersion = 23)
+ @Test fun resourceResolve_withSelectorColorWithAttribute_resolvesDefaultColor() {
+ val deferred = DeferredColor.Resource(R.color.stateful_color_with_attr)
+ assertThat(deferred.resolve(AppCompatContext())).isEqualTo(Color.parseColor("#987654"))
+ }
+ //endregion
+
+ //region Attribute
+ @Test fun attributeResolve_withStandardColor_resolvesColor() {
  val deferred = DeferredColor.Attribute(R.attr.colorPrimary)
- assertThat(deferred.resolve(AppCompatContext())).isEqualTo(Color.parseColor("#212121"))
+ assertThat(deferred.resolve(AppCompatContext())).isEqualTo(Color.parseColor("#987654"))
+ }
+
+ @Test fun attributeResolve_withSelectorColor_resolvesDefaultColor() {
+ val deferred = DeferredColor.Attribute(R.attr.subtitleTextColor)
+ assertThat(deferred.resolve(AppCompatContext())).isEqualTo(Color.parseColor("#aaaaaa"))
+ }
+
+ @SdkSuppress(minSdkVersion = 23)
+ @Test fun attributeResolve_withSelectorColorWithAttributeDefault_resolvesDefaultColor() {
+ val deferred = DeferredColor.Attribute(R.attr.titleTextColor)
+ assertThat(deferred.resolve(AppCompatContext())).isEqualTo(Color.parseColor("#987654"))
  }
 
  @Test(expected = IllegalArgumentException::class)
- fun attribute_withUnknownAttribute_throwsException() {
+ fun attributeResolve_withUnknownAttribute_throwsException() {
  val deferred = DeferredColor.Attribute(R.attr.colorPrimary)
 
  // Default-theme context does not have <colorPrimary> attribute:
  deferred.resolve(context)
  }
 
  @Test(expected = IllegalArgumentException::class)
- fun attribute_withWrongAttributeType_throwsException() {
+ fun attributeResolve_withWrongAttributeType_throwsException() {
  val deferred = DeferredColor.Attribute(R.attr.isLightTheme)
 
  deferred.resolve(AppCompatContext())
  }
+ //endregion
 }

deferred-resources/src/androidTest/java/com/backbase/deferredresources/TestContext.kt

@@ -25,7 +25,7 @@ internal fun AppCompatContext(
  light: Boolean = false
 ): Context = ContextThemeWrapper(
  context,
- if (light) R.style.Theme_AppCompat_Light else R.style.Theme_AppCompat
+ if (light) R.style.TestTheme_Light else R.style.TestTheme
 )
 
 //region Configuration

deferred-resources/src/androidTest/res/color/stateful_color_with_attr.xml

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="utf-8"?>
+<selector xmlns:android="http://schemas.android.com/apk/res/android">
+
+ <item android:color="#dbdbdb" android:state_enabled="false" />
+
+ <item android:color="@android:color/darker_gray" android:state_checked="true" />
+
+ <item android:color="?colorPrimary" />
+
+</selector>

deferred-resources/src/androidTest/res/color/stateful_color_without_attr.xml

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="utf-8"?>
+<selector xmlns:android="http://schemas.android.com/apk/res/android">
+
+ <item android:color="#dbdbdb" android:state_enabled="false" />
+
+ <item android:color="@android:color/darker_gray" />
+
+</selector>

deferred-resources/src/androidTest/res/values/test_theme.xml

@@ -0,0 +1,14 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+ <style name="TestTheme" parent="Theme.AppCompat">
+ <item name="colorPrimary">#987654</item>
+ <item name="titleTextColor">@color/stateful_color_with_attr</item>
+ <item name="subtitleTextColor">@color/stateful_color_without_attr</item>
+ </style>
+
+ <style name="TestTheme.Light" parent="Theme.AppCompat.Light">
+ <item name="colorPrimary">#987654</item>
+ <item name="titleTextColor">@color/stateful_color_with_attr</item>
+ <item name="subtitleTextColor">@color/stateful_color_without_attr</item>
+ </style>
+</resources>

deferred-resources/src/main/java/com/backbase/deferredresources/DeferredColor.kt

@@ -1,6 +1,7 @@
 package com.backbase.deferredresources
 
 import android.content.Context
+import android.content.res.ColorStateList
 import android.graphics.Color
 import android.util.TypedValue
 import androidx.annotation.AttrRes
@@ -45,7 +46,12 @@ interface DeferredColor {
  @ColorRes private val resId: Int
  ) : DeferredColor {
  /**
- * Resolve [resId] to a [ColorInt] with the given [context].
+ * Resolve [resId] to a [ColorInt] with the given [context]. If [resId] resolves to a color selector resource,
+ * resolves the default color of that selector.
+ *
+ * Warning: On API < 23, resolving a color selector with [context]'s theme is unsupported. Thus, a color
+ * selector with an attribute reference as its default color will not resolve to the correct color on API 22 and
+ * below. A color selector with a resource reference as its default color will resolve correctly.
  */
  @ColorInt override fun resolve(context: Context): Int = ContextCompat.getColor(context, resId)
  }
@@ -61,19 +67,39 @@ interface DeferredColor {
  private val reusedTypedValue = TypedValue()
 
  /**
- * Resolve [resId] to a [ColorInt] with the given [context]'s theme.
+ * Resolve [resId] to a [ColorInt] with the given [context]'s theme. If [resId] would resolve a color selector,
+ * resolves to the default color of that selector.
+ *
+ * Warning: On API < 23, resolving a color selector with [context]'s theme is unsupported. Thus, a color
+ * selector with an attribute reference as its default color will not resolve to the correct color on API 22 and
+ * below. A color selector with a resource reference as its default color will resolve correctly.
  *
  * @throws IllegalArgumentException if [resId] cannot be resolved to a color.
  */
- @ColorInt override fun resolve(context: Context): Int = context.resolveColorAttribute(resId)
-
- @ColorInt private fun Context.resolveColorAttribute(@AttrRes resId: Int): Int =
- resolveAttribute(
- resId, "color", reusedTypedValue,
- TypedValue.TYPE_INT_COLOR_RGB8, TypedValue.TYPE_INT_COLOR_ARGB8,
- TypedValue.TYPE_INT_COLOR_RGB4, TypedValue.TYPE_INT_COLOR_ARGB4
- ) {
+ @ColorInt override fun resolve(context: Context): Int = context.resolveColorAttribute {
+ if (type == TypedValue.TYPE_STRING)
+ context.resolveColorStateList().defaultColor
+ else
  data
- }
+ }
+
+ private inline fun <T> Context.resolveColorAttribute(
+ toTypeSafeResult: TypedValue.() -> T
+ ): T = resolveAttribute(
+ resId, "color", reusedTypedValue,
+ TypedValue.TYPE_INT_COLOR_RGB8, TypedValue.TYPE_INT_COLOR_ARGB8,
+ TypedValue.TYPE_INT_COLOR_RGB4, TypedValue.TYPE_INT_COLOR_ARGB4,
+ TypedValue.TYPE_STRING,
+ toTypeSafeResult = toTypeSafeResult
+ )
+
+ private fun Context.resolveColorStateList(): ColorStateList = resolveAttribute(
+ resId, "reference", reusedTypedValue,
+ TypedValue.TYPE_REFERENCE,
+ resolveRefs = false
+ ) {
+ val colorSelectorResId = data
+ ContextCompat.getColorStateList(this@resolveColorStateList, colorSelectorResId)!!
+ }
  }
 }

deferred-resources/src/main/java/com/backbase/deferredresources/internal/Context.kt

@@ -28,10 +28,11 @@ internal inline fun <T> Context.resolveAttribute(
  attributeTypeName: String,
  reusedTypedValue: TypedValue,
  vararg expectedTypes: Int,
+ resolveRefs: Boolean = true,
  toTypeSafeResult: TypedValue.() -> T
 ): T {
  try {
- val isResolved = theme.resolveAttribute(resId, reusedTypedValue, true)
+ val isResolved = theme.resolveAttribute(resId, reusedTypedValue, resolveRefs)
  if (isResolved && expectedTypes.contains(reusedTypedValue.type))
  return reusedTypedValue.toTypeSafeResult()
  else
@@ -53,13 +54,13 @@ private fun Context.createErrorMessage(
 ) = try {
  val name = resources.getResourceEntryName(resId)
  val couldNotResolve = "Could not resolve attribute <$name>"
- val withContext = "with <$this>"
+ val withContext = "with context <$this>"
  if (isResolved)
  "$couldNotResolve to a $attributeTypeName $withContext"
  else
  "$couldNotResolve $withContext"
 } catch (notFoundException: Resources.NotFoundException) {
- "Attribute <$resId> could not be found with <$this>"
+ "Attribute <$resId> could not be found with context <$this>"
 }
 
 /**