Early implementation of custom icon handling

As requested by #86, this feature allows the user to be able to select
an icon from icon packs, replacing the default and/or existing icons
provided by the current icon pack.

This implementation caches the icon into a PNG, saving it to the
launcher's files directory. This means that it is not saved to a backup,
but it will persist even if the source of this icon (the icon pack where
icon came from) is removed.

At the moment, there should be a consideration on the use of simple
index instead of having to cache an entire file to save on space, but
this works for now.

app/src/main/java/mono/hg/helpers/LauncherIconHelper.kt

@@ -7,6 +7,7 @@ import android.content.pm.LauncherApps
 import android.content.pm.PackageManager
 import android.content.res.Resources
 import android.graphics.Bitmap
+import android.graphics.BitmapFactory
 import android.graphics.BlurMaskFilter
 import android.graphics.Canvas
 import android.graphics.Color
@@ -26,6 +27,8 @@ import mono.hg.utils.Utils.LogLevel
 import org.xmlpull.v1.XmlPullParser
 import org.xmlpull.v1.XmlPullParserException
 import org.xmlpull.v1.XmlPullParserFactory
+import java.io.File
+import java.io.FileOutputStream
 import java.io.IOException
 import java.util.*
 
@@ -97,6 +100,29 @@ object LauncherIconHelper {
         return getDefaultIconDrawable(activity, componentName, user)
     }
 
+    /**
+     * Caches an icon to the launcher's files directory.
+     *
+     * This is only used for custom icon.
+     * Most icons are not cached to save on space.
+     *
+     * @param context       Context required to retrieve the path to the files directory.
+     * @param bitmap        The Bitmap to cache.
+     * @param componentName The component name that will use this cached Bitmap.
+     *                      This component name will be reduced to package name.
+     */
+    fun cacheIcon(context: Context, bitmap: Bitmap, componentName: String) {
+        try {
+            FileOutputStream(context.filesDir.path + File.separatorChar + componentName).apply {
+                bitmap.compress(Bitmap.CompressFormat.PNG, 100, this) // Quality is unused here.
+                flush()
+                close()
+            }
+        } catch (e: Exception) {
+            Utils.sendLog(3, e.toString())
+        }
+    }
+
     private fun drawAdaptiveShadow(resources: Resources, icon: Drawable): BitmapDrawable {
         return BitmapDrawable(resources, addShadow(icon, icon.intrinsicHeight, icon.intrinsicWidth))
     }
@@ -324,8 +350,21 @@ object LauncherIconHelper {
         val iconPackageName =
             PreferenceHelper.preference.getString("icon_pack", "default") ?: "default"
         val defaultIcon: Drawable? = getDefaultIconDrawable(activity, appPackageName, user)
+        val customIconPath =
+            activity.filesDir.path + File.separatorChar + AppUtils.getPackageName(appPackageName)
 
         try {
+            // If there is a custom icon set, use that over the default one.
+            with(File(customIconPath)) {
+                if (exists() && ! isDirectory) {
+                    BitmapFactory.Options().apply {
+                        inPreferredConfig = Bitmap.Config.ARGB_8888
+                    }.also {
+                        return BitmapDrawable(activity.resources, BitmapFactory.decodeFile(this.path, it))
+                    }
+                }
+            }
+
             val iconRes = if ("default" != iconPackageName) {
                 packageManager.getResourcesForApplication(iconPackageName)
             } else {
@@ -430,7 +469,11 @@ object LauncherIconHelper {
         return BitmapDrawable(resources, result)
     }
 
-    private fun getDefaultIconDrawable(activity: Activity, appPackageName: String, user:Long): Drawable? {
+    private fun getDefaultIconDrawable(
+        activity: Activity,
+        appPackageName: String,
+        user: Long
+    ): Drawable? {
         return if (Utils.atLeastLollipop()) {
             try {
                 val launcher =

app/src/main/java/mono/hg/pages/AppsListPage.kt

@@ -1,12 +1,15 @@
 package mono.hg.pages
 
+import android.app.Activity.RESULT_OK
 import android.content.BroadcastReceiver
 import android.content.Context
 import android.content.Intent
 import android.content.IntentFilter
 import android.content.pm.LauncherApps
 import android.content.pm.PackageManager
 import android.content.res.ColorStateList
+import android.graphics.Bitmap
+import android.graphics.drawable.BitmapDrawable
 import android.net.Uri
 import android.os.Bundle
 import android.os.UserManager
@@ -58,6 +61,11 @@ import kotlin.collections.ArrayList
  * This is the generic implementation of an app list that handles the required features.
  */
 class AppsListPage : GenericPage() {
+    /*
+     * Index of an app that is currently being edited.
+     */
+    private var editingAppPosition: Int = -1
+
     /*
      * Adapter for installed apps.
      */
@@ -309,6 +317,29 @@ class AppsListPage : GenericPage() {
         }
     }
 
+    override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
+        super.onActivityResult(requestCode, resultCode, data)
+
+        // Update the icon on the selected app.
+        if (resultCode == RESULT_OK && requestCode == SET_ICON_REQUEST) {
+            data?.getParcelableExtra<Bitmap>("icon")?.let { bitmap ->
+                appsAdapter.getItem(editingAppPosition).apply {
+                    this?.packageName?.let {
+                        LauncherIconHelper.cacheIcon(
+                            requireContext(),
+                            bitmap,
+                            AppUtils.getPackageName(it)
+                        )
+                    }
+                    this?.icon = BitmapDrawable(resources, bitmap)
+                }?.let { appsAdapter.updateItem(it) }
+            }
+
+            // Reset the index once we're done.
+            editingAppPosition = -1
+        }
+    }
+
     override fun isAcceptingSearch(): Boolean {
         return true
     }
@@ -363,6 +394,20 @@ class AppsListPage : GenericPage() {
             show()
             setOnMenuItemClickListener { item ->
                 when (item.itemId) {
+                    R.id.action_icon -> {
+                        // Update the index first.
+                        editingAppPosition = appsAdapter.getGlobalPositionOf(app)
+
+                        // Load the picker intent.
+                        // TODO: We should use more intent actions here.
+                        Intent("org.adw.launcher.icons.ACTION_PICK_ICON").apply {
+                            startActivityForResult(
+                                Intent.createChooser(
+                                    this, getString(R.string.dialog_title_set_icon)
+                                ), SET_ICON_REQUEST
+                            )
+                        }
+                    }
                     R.id.action_pin -> getLauncherActivity().pinAppHere(app.userPackageName, user)
                     R.id.action_info -> AppUtils.openAppDetails(
                         requireActivity(),
@@ -494,7 +539,8 @@ class AppsListPage : GenericPage() {
     private fun addApp(list: MutableList<App>, componentName: String, user: Long) {
         // Don't add the app if it has the launcher's package name or if it's hidden.
         if (componentName.contains(requireContext().packageName) ||
-            excludedAppsList.contains(componentName)) {
+            excludedAppsList.contains(componentName)
+        ) {
             return
         }
 
@@ -631,5 +677,6 @@ class AppsListPage : GenericPage() {
 
     companion object {
         private const val SHORTCUT_MENU_GROUP = 247
+        private const val SET_ICON_REQUEST = 8000
     }
 }

app/src/main/res/menu/menu_app.xml

@@ -10,6 +10,11 @@
         android:title="@string/action_actions">
 
         <menu android:id="@+id/menu_app_actions">
+            <item
+                android:id="@+id/action_icon"
+                android:orderInCategory="100"
+                android:title="@string/action_icon"
+                app:showAsAction="never" />
 
             <item
                 android:id="@+id/action_unpin"

app/src/main/res/values/strings.xml

@@ -15,6 +15,7 @@
     <string name="action_web_provider_add">Add</string>
     <string name="action_web_provider_reset">Reset</string>
     <!-- App menu actions -->
+    <string name="action_icon">Icon</string>
     <string name="action_pin">Pin</string>
     <string name="action_unpin">Unpin</string>
     <string name="action_hide">Hide</string>
@@ -29,9 +30,12 @@
     <string name="search_web_hint">Search for \'%1$s\' online</string>
     <string name="search_web_button_prompt">With</string>
     <string name="search_web_button">Go</string>
+    <!-- Dialog titles -->
     <string name="dialog_title_add_provider">Add provider</string>
     <string name="dialog_title_edit_provider">Edit provider</string>
     <string name="dialog_title_shorthand">Set shorthand</string>
+    <string name="dialog_title_set_icon">Select icon pack</string>
+    <!-- Dialog actions -->
     <string name="dialog_action_close">Close</string>
     <string name="dialog_action_add">Add</string>
     <string name="dialog_action_edit">Edit</string>
@@ -40,7 +44,7 @@
     <string name="err_invalid_url">Invalid URL.</string>
     <string name="err_provider_exists">Search engine name must be unique.</string>
     <string name="err_no_method_panel">This is only possible on newer Android.</string>
-    <!-- Start up dialogue, shown to new user -->
+    <!-- Start up dialog, shown to new user -->
     <string name="dialog_start_hint_title">Welcome!</string>
     <string name="dialog_start_hint_message_one">This is your desktop. In here, you can…\n
         • Tap to open the app list\n