Add new "Enable /sdcard" menu option that requests the

WRITE_EXTERNAL_STORAGE permission even if it's already been requested
once before on startup, because changing from SDK 30 to SDK 29 appears to
clear it.

app/build.gradle

@@ -25,7 +25,7 @@ android {
     defaultConfig {
         applicationId "org.galexander.sshd"
         minSdkVersion 17
-        targetSdkVersion 30
+        targetSdkVersion 29
 
         versionCode 26
         versionName "26"

app/src/main/AndroidManifest.xml

@@ -10,7 +10,8 @@
     <uses-feature android:name="android.hardware.touchscreen" android:required="false" />
     <application android:label="SimpleSSHD" android:icon="@drawable/icon"
 	  android:allowBackup="false" android:banner="@drawable/tvbanner"
-	  android:usesCleartextTraffic="true">
+	  android:usesCleartextTraffic="true"
+	  android:requestLegacyExternalStorage="true">
         <activity android:name="SimpleSSHD" android:label="SimpleSSHD"
 	    android:launchMode="singleTask">
             <intent-filter>

app/src/main/java/org/galexander/sshd/SimpleSSHD.java

@@ -53,7 +53,7 @@ public class SimpleSSHD extends Activity
 		synchronized (lock) {
 			curr = this;
 		}
-		permission();
+		permission_startup();
 		update_startstop_prime();
 		updater = new UpdaterThread();
 		updater.start();
@@ -88,6 +88,9 @@ public class SimpleSSHD extends Activity
 			case R.id.resetkeys:
 				resetkeys_clicked(null);
 				return true;
+			case R.id.trypermission:
+				permission_clicked(null);
+				return true;
 			case R.id.doc:
 				doc_clicked(null);
 				return true;
@@ -111,6 +114,9 @@ public class SimpleSSHD extends Activity
 	public void resetkeys_clicked(View v) {
 		reset_keys();
 	}
+	public void permission_clicked(View v) {
+		permission_menu();
+	}
 	public void doc_clicked(View v) {
 		try {
 			Intent i = new Intent(Intent.ACTION_VIEW);
@@ -312,7 +318,7 @@ public class SimpleSSHD extends Activity
 		}
 	}
 
-	public void permission() {
+	private void permission_startup() {
 		if (android.os.Build.VERSION.SDK_INT < 23) {
 			return;
 		}
@@ -325,6 +331,22 @@ public class SimpleSSHD extends Activity
 		requestPermissions(new String[] { Manifest.permission.WRITE_EXTERNAL_STORAGE }, 0);
 	}
 
+	private void toast(String s) {
+		Toast.makeText(this, s, Toast.LENGTH_LONG).show();
+	}
+
+	private void permission_menu() {
+		if (android.os.Build.VERSION.SDK_INT < 23) {
+			toast("Your phone uses an Android version that grants external storage access by default.");
+			return;
+		}
+		if (checkSelfPermission(Manifest.permission.WRITE_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED) {
+			toast("External storage permission already granted.");
+			return;
+		}
+		requestPermissions(new String[] { Manifest.permission.WRITE_EXTERNAL_STORAGE }, 0);
+	}
+
 	public void onRequestPermissionsResult(int code, String[] perms, int[] results) {
 		Prefs.set_requested();	/* whatever result, don't ask again */
 	}

app/src/main/res/layout/main_tv.xml

@@ -61,9 +61,12 @@
 	    android:text="Reset Keys"
 	    android:onClick="resetkeys_clicked" />
 	<Button style="@style/tv_button" android:id="@+id/option4"
+	    android:text="Enable /sdcard"
+	    android:onClick="permission_clicked" />
+	<Button style="@style/tv_button" android:id="@+id/option5"
 	    android:text="Documentation"
 	    android:onClick="doc_clicked" />
-	<Button style="@style/tv_button" android:id="@+id/option5"
+	<Button style="@style/tv_button" android:id="@+id/option6"
 	    android:nextFocusDown="@+id/startstop"
 	    android:text="About"
 	    android:onClick="about_clicked" />

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

@@ -10,6 +10,8 @@ button list in res/layout/main_tv.xml -->
     <item android:id="@+id/resetkeys"
           android:icon="@android:drawable/ic_secure"
           android:title="Reset Keys" />
+    <item android:id="@+id/trypermission"
+          android:title="Enable /sdcard" />
     <item android:id="@+id/doc"
           android:icon="@android:drawable/ic_menu_help"
           android:title="Documentation" />