🔒 Fix permission

app/build.gradle

@@ -25,7 +25,8 @@ dependencies {
     implementation fileTree(dir: 'libs', include: ['*.jar'])
     implementation 'androidx.legacy:legacy-support-v4:1.0.0'
     implementation 'androidx.constraintlayout:constraintlayout:2.0.2'
-    implementation "androidx.activity:activity:1.1.0"
+    implementation "androidx.activity:activity-ktx:1.2.0-beta01"
+    implementation 'androidx.fragment:fragment-ktx:1.3.0-beta01'
     androidTestImplementation('androidx.test.espresso:espresso-core:3.1.0', {
         exclude group: 'com.android.support', module: 'support-annotations'
     })

app/src/main/AndroidManifest.xml

@@ -10,11 +10,12 @@
 
     <application
         android:debuggable="false"
+        android:requestLegacyExternalStorage="true"
         android:allowBackup="true"
         android:icon="@mipmap/ic_launcher"
         android:label="@string/app_name"
         android:supportsRtl="true"
-        android:theme="@style/AppTheme">
+        android:theme="@style/Theme.AppCompat">
         <activity android:name=".ChooseDeckActivity"
 			android:screenOrientation="landscape"></activity>
         <activity android:name=".ChooseGuestActivity"

app/src/main/java/sma/rhythmtapper/MainActivity.kt

@@ -1,17 +1,40 @@
 package sma.rhythmtapper
 
-import android.app.Activity
+import android.Manifest
 import android.content.Intent
+import android.content.pm.PackageManager
 import android.os.Bundle
+import android.os.Environment
+import android.provider.Settings
+import androidx.activity.result.contract.ActivityResultContracts
+import androidx.appcompat.app.AppCompatActivity
+import androidx.core.content.ContextCompat
 import kotlinx.android.synthetic.main.activity_main.*
+import java.io.File
 
-class MainActivity : Activity() {
+class MainActivity : AppCompatActivity() {
+    val requestPermissionLauncher =
+            registerForActivityResult(ActivityResultContracts.RequestPermission()
+            ) { isGranted: Boolean ->
+                if (isGranted) {
+                    // Permission is granted. Continue the action or workflow in your
+                    // app.
+                } else {
+                    // Explain to the user that the feature is unavailable because the
+                    // features requires a permission that the user has denied. At the
+                    // same time, respect the user's decision. Don't link to system
+                    // settings in an effort to convince the user to change their
+                    // decision.
+                }
+            }
+
+    val sdcardFile = Environment.getExternalStorageDirectory()
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         setContentView(R.layout.activity_main)
         main_btn_start.setOnClickListener {
             var text = etPath.text.toString()
-            if (text.isEmpty()) text = "/sdcard/Android/data/com.nomansland.tempestwave/files/"
+            if (text.isEmpty()) text = File(sdcardFile, "Android/data/com.nomansland.tempestwave/files/").canonicalPath
             val i = Intent(this@MainActivity, DifficultySelectionActivity::class.java)
             i.putExtra("path", text)
             this@MainActivity.startActivity(i)
@@ -24,7 +47,29 @@ class MainActivity : Activity() {
             val i = Intent(this@MainActivity, AboutActivity::class.java)
             this@MainActivity.startActivity(i)
         }
+        when {
+            ContextCompat.checkSelfPermission(
+                    applicationContext,
+                    Manifest.permission.READ_EXTERNAL_STORAGE
+            ) == PackageManager.PERMISSION_GRANTED -> {
+                // You can use the API that requires the permission.
+            }
+            else -> {
+                // You can directly ask for the permission.
+                // The registered ActivityResultCallback gets the result of this request.
+                requestPermissionLauncher.launch(
+                        Manifest.permission.READ_EXTERNAL_STORAGE)
+            }
+        }
 
+        if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.R) {
+            if (!Environment.isExternalStorageManager()) {
+                startActivity(Intent(Settings.ACTION_MANAGE_ALL_FILES_ACCESS_PERMISSION))
+            }
+        } else {
+//            TODO("VERSION.SDK_INT < R")
+
+        }
 //        requestPermission
     }
 }