Make "Up" and "Overflow" menu icons more visible in AccountProfile (#3272)

* Make "Up" and "Overflow" menu icons more visible in AccountProfile

The toolbar in AccountProfile is transparent, so any profile image the user
has chosen is shown under it.

This makes the "Up" and "Overflow" menu icons also have transparent
backgrouns.

Consequently, they can be hard to spot, or possibly invisible, on backgrounds
that are very dark or very light.

Fix this by compositing the icons in a LayerDrawable, with a circular
background identical to the surface colour. This ensures they stand out
against the background image, and blend in when the user scrolls.

* Get and reuse the background drawable

* Apply a smidgen of transparency

app/src/main/java/com/keylesspalace/tusky/components/account/AccountActivity.kt

@@ -22,6 +22,7 @@ import android.content.Context
 import android.content.Intent
 import android.content.res.ColorStateList
 import android.graphics.Color
+import android.graphics.drawable.LayerDrawable
 import android.os.Bundle
 import android.text.Editable
 import android.view.Menu
@@ -32,6 +33,7 @@ import androidx.activity.viewModels
 import androidx.annotation.ColorInt
 import androidx.annotation.Px
 import androidx.appcompat.app.AlertDialog
+import androidx.appcompat.content.res.AppCompatResources
 import androidx.core.app.ActivityOptionsCompat
 import androidx.core.view.ViewCompat
 import androidx.core.view.WindowCompat
@@ -299,6 +301,23 @@ class AccountActivity : BottomSheetActivity(), ActionButtonActivity, HasAndroidI
         toolbarBackground.fillColor = ColorStateList.valueOf(Color.TRANSPARENT)
         binding.accountToolbar.background = toolbarBackground
 
+        // Provide a non-transparent background to the navigation and overflow icons to ensure
+        // they remain visible over whatever the profile background image might be.
+        val backgroundCircle = AppCompatResources.getDrawable(this, R.drawable.background_circle)!!
+        backgroundCircle.alpha = 210 // Any lower than this and the backgrounds interfere
+        binding.accountToolbar.navigationIcon = LayerDrawable(
+            arrayOf(
+                backgroundCircle,
+                binding.accountToolbar.navigationIcon
+            )
+        )
+        binding.accountToolbar.overflowIcon = LayerDrawable(
+            arrayOf(
+                backgroundCircle,
+                binding.accountToolbar.overflowIcon
+            )
+        )
+
         binding.accountHeaderInfoContainer.background = MaterialShapeDrawable.createWithElevationOverlay(this, appBarElevation)
 
         val avatarBackground = MaterialShapeDrawable.createWithElevationOverlay(this, appBarElevation).apply {

app/src/main/res/drawable/background_circle.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<shape xmlns:android="http://schemas.android.com/apk/res/android"
+    android:shape="oval">
+    <solid android:color="?attr/colorSurface" />
+</shape>