Add GPU Driver Configuration preference

This preference launches `GpuDriverActivity` for managing custom gpu drivers. When the device has an incompatible GPU, the preference will be disabled and greyed out.

app/src/main/java/emu/skyline/preference/GpuDriverPreference.kt

@@ -0,0 +1,52 @@
+/*
+ * SPDX-License-Identifier: MPL-2.0
+ * Copyright © 2020 Skyline Team and Contributors (https://github.com/skyline-emu/)
+ */
+
+package emu.skyline.preference
+
+import android.content.Context
+import android.content.Intent
+import android.util.AttributeSet
+import androidx.activity.ComponentActivity
+import androidx.activity.result.contract.ActivityResultContracts
+import androidx.preference.Preference
+import androidx.preference.Preference.SummaryProvider
+import androidx.preference.R
+import emu.skyline.utils.GpuDriverHelper
+import emu.skyline.utils.PreferenceSettings
+import emu.skyline.R as SkylineR
+
+/**
+ * This preference is used to launch [GpuDriverActivity] using a preference
+ */
+class GpuDriverPreference @JvmOverloads constructor(context : Context, attrs : AttributeSet? = null, defStyleAttr : Int = R.attr.preferenceStyle) : Preference(context, attrs, defStyleAttr) {
+    private val driverCallback = (context as ComponentActivity).registerForActivityResult(ActivityResultContracts.StartActivityForResult()) {
+        notifyChanged()
+    }
+
+    init {
+        val supportsCustomDriverLoading = GpuDriverHelper.supportsCustomDriverLoading()
+        if (supportsCustomDriverLoading) {
+            summaryProvider = SummaryProvider<GpuDriverPreference> {
+                sharedPreferences?.getString(key, PreferenceSettings.SYSTEM_GPU_DRIVER)?.let {
+                    var driver = it
+                    if (it == PreferenceSettings.SYSTEM_GPU_DRIVER)
+                        driver = context.getString(SkylineR.string.system_driver)
+
+                    context.getString(SkylineR.string.gpu_driver_config_desc, driver)
+                }
+            }
+        } else {
+            isEnabled = false
+            summaryProvider = SummaryProvider<GpuDriverPreference> {
+                context.getString(SkylineR.string.gpu_driver_config_desc_unsupported)
+            }
+        }
+    }
+
+    /**
+     * This launches [GpuDriverActivity] on click to manage driver packages
+     */
+    override fun onClick() = driverCallback.launch(Intent(context, GpuDriverActivity::class.java))
+}

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

@@ -37,6 +37,8 @@
     <string name="perf_stats_desc_on">Performance Statistics will be shown in the top-left corner</string>
     <string name="log_level">Log Level</string>
     <string name="gpu_driver_config">GPU Driver Configuration</string>
+    <string name="gpu_driver_config_desc">Active driver: %1$s</string>
+    <string name="gpu_driver_config_desc_unsupported">Your GPU is not supported</string>
     <!-- Settings - System -->
     <string name="system">System</string>
     <string name="use_docked">Use Docked Mode</string>

app/src/main/res/xml/preferences.xml

@@ -40,6 +40,9 @@
             app:key="log_level"
             app:title="@string/log_level"
             app:useSimpleSummaryProvider="true" />
+        <emu.skyline.preference.GpuDriverPreference
+            app:key="gpu_driver"
+            app:title="@string/gpu_driver_config" />
     </PreferenceCategory>
     <PreferenceCategory
         android:key="category_keys"