Add optional color with default value for LabelChipView.kt

app/src/androidTest/java/ch/protonmail/android/ui/view/MultiLineLabelChipGroupViewTest.kt

@@ -91,7 +91,8 @@ class MultiLineLabelChipGroupViewTest : ViewTest<MultiLineLabelChipGroupView>(::
 
         // then
         for (label in labels) {
-            onView(withText(label.name.s)).check(matches(withBackgroundColor(label.color)))
+            val labelColor = checkNotNull(label.color)
+            onView(withText(label.name.s)).check(matches(withBackgroundColor(labelColor)))
         }
     }
 

app/src/androidTest/java/ch/protonmail/android/ui/view/SingleLineLabelChipGroupViewTest.kt

@@ -104,9 +104,12 @@ class SingleLineLabelChipGroupViewTest : ViewTest<SingleLineLabelChipGroupView>(
         chipGroupView.setLabels(labels)
 
         // then
+        val (expectedLabelName, expectedLabelColor) = with(labels.first()) {
+            name.s to checkNotNull(color)
+        }
         onLabelView()
-            .check(matches(withText(testLabelsList.first().name.s)))
-            .check(matches(withBackgroundColor(testLabelsList.first().color)))
+            .check(matches(withText(expectedLabelName)))
+            .check(matches(withBackgroundColor(expectedLabelColor)))
     }
 
     @Test

app/src/main/java/ch/protonmail/android/ui/view/LabelChipView.kt

@@ -24,6 +24,7 @@ import android.content.res.ColorStateList
 import android.graphics.Color
 import android.text.TextUtils
 import android.util.AttributeSet
+import androidx.annotation.ColorInt
 import androidx.appcompat.widget.AppCompatTextView
 import androidx.core.content.withStyledAttributes
 import androidx.recyclerview.widget.DiffUtil
@@ -44,6 +45,10 @@ class LabelChipView @JvmOverloads constructor(
     defStyleAttr: Int = android.R.attr.textViewStyle
 ) : AppCompatTextView(context, attrs, defStyleAttr) {
 
+    @get:ColorInt
+    private val defaultBackgroundTint: Int get() =
+        context.getColor(R.color.shade_60)
+
     init {
         // Padding
         val horizontalPadding = resources.getDimensionPixelSize(R.dimen.padding_m)
@@ -72,8 +77,8 @@ class LabelChipView @JvmOverloads constructor(
             .apply { fillColor = color }
     }
 
-    fun setLabelColor(color: Int) {
-        setLabelColor(ColorStateList.valueOf(color))
+    fun setLabelColor(@ColorInt color: Int?) {
+        setLabelColor(ColorStateList.valueOf(color ?: defaultBackgroundTint))
     }
 
     private fun buildBackgroundShape() = ShapeAppearanceModel
@@ -88,10 +93,16 @@ class LabelChipView @JvmOverloads constructor(
     }
 }
 
+/**
+ * Ui Model for [LabelChipView]
+ * @property color is the [ColorInt] that will be applied as background.
+ *  if `null` a default background will be used, for ensure readability of the text
+ */
 data class LabelChipUiModel(
     val id: Id,
     val name: Name,
-    val color: Int
+    @ColorInt
+    val color: Int?
 ) {
 
     companion object {