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 can't be saved to when
backing up the launcher configuration,
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