Add workaround for Alt+Shift+6

Re #321

Author: gujjwal00

app/src/androidTest/java/com/gaurav/avnc/ui/vnc/KeyHandlerTest.kt

@@ -141,6 +141,17 @@ class KeyHandlerTest {
         assertEquals('A'.code, dispatchedKeyDowns[1])
     }
 
+    @Test
+    fun altShift6() {
+        sendDown(KeyEvent.KEYCODE_SHIFT_LEFT)
+        sendDown(KeyEvent.KEYCODE_ALT_LEFT)
+        sendKeyWithMeta(KeyEvent.KEYCODE_6, KeyEvent.META_SHIFT_ON or KeyEvent.META_ALT_ON)
+        assertEquals(XKeySym.XK_Shift_L, dispatchedKeyDowns[0])
+        assertEquals(XKeySym.XK_Alt_L, dispatchedKeyDowns[1])
+        assertEquals('^'.code, dispatchedKeyDowns[2])
+        assertEquals('^'.code, dispatchedKeyUps[0])
+    }
+
     @Test
     fun charWithCapslock() {
         sendKeyWithMeta(KeyEvent.KEYCODE_A, KeyEvent.META_CAPS_LOCK_ON)

app/src/main/java/com/gaurav/avnc/ui/vnc/KeyHandler.kt

@@ -444,7 +444,12 @@ class KeyHandler(private val dispatcher: Dispatcher, prefs: AppPreferences) {
      */
     private fun getUnicodeChar(event: KeyEvent): Int {
         var metaState = event.metaState or vkMetaState
-        val uChar = event.getUnicodeChar(metaState)
+        var uChar = event.getUnicodeChar(metaState)
+
+        // Fix for Alt+Shift+6 (Android generates ACCENT_CIRCUMFLEX, but we want '^')
+        if (event.keyCode == KeyEvent.KEYCODE_6 && metaState != 0 && (uChar and KeyCharacterMap.COMBINING_ACCENT) != 0)
+            uChar = '^'.code
+
         if (uChar != 0 || metaState == 0)
             return uChar