make arrow keys repeatable (#932)

only applies to keyboard keys, not in toolbar

app/src/main/java/helium314/keyboard/keyboard/Key.java

@@ -1171,13 +1171,17 @@ public class Key implements Comparable<Key> {
             if (mCode <= Constants.CODE_SPACE && mCode != KeyCode.MULTIPLE_CODE_POINTS && mIconName == null)
                 actionFlags |= ACTION_FLAGS_NO_KEY_PREVIEW;
             switch (mCode) {
-                case KeyCode.DELETE, KeyCode.SHIFT, Constants.CODE_ENTER, KeyCode.SHIFT_ENTER, KeyCode.ALPHA, Constants.CODE_SPACE, KeyCode.NUMPAD,
+            case KeyCode.DELETE, KeyCode.ARROW_LEFT, KeyCode.ARROW_RIGHT, KeyCode.ARROW_UP, KeyCode.ARROW_DOWN:
-                        KeyCode.SYMBOL, KeyCode.SYMBOL_ALPHA, KeyCode.LANGUAGE_SWITCH, KeyCode.EMOJI, KeyCode.CLIPBOARD -> actionFlags |= ACTION_FLAGS_NO_KEY_PREVIEW; // no preview even if icon!
+                // repeating is disabled if a key is configured with pop-ups
+                if (mPopupKeys == null)
+                    actionFlags |= ACTION_FLAGS_IS_REPEATABLE;
+                // fallthrough
+            case KeyCode.SHIFT, Constants.CODE_ENTER, KeyCode.SHIFT_ENTER, KeyCode.ALPHA, Constants.CODE_SPACE, KeyCode.NUMPAD,
+                    KeyCode.SYMBOL, KeyCode.SYMBOL_ALPHA, KeyCode.LANGUAGE_SWITCH, KeyCode.EMOJI, KeyCode.CLIPBOARD:
+                actionFlags |= ACTION_FLAGS_NO_KEY_PREVIEW; // no preview even if icon!
             }
             if (mCode == KeyCode.SETTINGS || mCode == KeyCode.LANGUAGE_SWITCH)
                 actionFlags |= ACTION_FLAGS_ALT_CODE_WHILE_TYPING;
-            if (mCode == KeyCode.DELETE)
-                actionFlags |= ACTION_FLAGS_IS_REPEATABLE;
             mActionFlags = actionFlags;
 
             final int altCodeInAttr; // settings and language switch keys have alt code space, all others nothing

app/src/main/java/helium314/keyboard/latin/LatinIME.java

@@ -1731,9 +1731,16 @@ public class LatinIME extends InputMethodService implements
             return;
         }
         if (repeatCount > 0) {
-            if (code == KeyCode.DELETE && !mInputLogic.mConnection.canDeleteCharacters()) {
+            // No need to feedback when repeat delete/cursor keys will have no effect.
-                // No need to feedback when repeat delete key will have no effect.
+            switch (code) {
+            case KeyCode.DELETE, KeyCode.ARROW_LEFT, KeyCode.ARROW_UP:
+                if (!mInputLogic.mConnection.canDeleteCharacters())
                     return;
+                break;
+            case KeyCode.ARROW_RIGHT, KeyCode.ARROW_DOWN:
+                if (!mInputLogic.mConnection.canForwardDeleteCharacters())
+                    return;
+                break;
             }
             // TODO: Use event time that the last feedback has been generated instead of relying on
             // a repeat count to thin out feedback.

app/src/main/java/helium314/keyboard/latin/RichInputConnection.java

@@ -363,6 +363,11 @@ public final class RichInputConnection implements PrivateCommandPerformer {
         return mExpectedSelStart > 0;
     }
 
+    public boolean canForwardDeleteCharacters() {
+        final CharSequence after = getTextAfterCursor(1, 0);
+        return !TextUtils.isEmpty(after);
+    }
+
     /**
      * Gets the caps modes we should be in after this specific string.
      * <p>

layouts.md

@@ -62,6 +62,7 @@ If the layout has exactly 2 keys in the bottom row, these keys will replace comm
 * `popup`: list of keys to add in the popup, e.g. `"label": ")", "popup": {"relevant": [{  "label": "." }]}` is a `)` key with a `.` popup
   * Note that in popup keys, properties are ignored with the exception of `$`, `code`, `codePoints`, and `label`
   * When specifying a _selector_ key class in a popup key, it will be evaluated correctly (e.g. for changing popups dependent on shift state)
+  * If popups are added to repeating keys (e.g. delete, arrow keys), repetition will be disabled.
 * `width`: width of the key in units of screen width, e.g. a key with `"width": 0.1` has a width of 10% of the screen, defaults to `0`
   * A special value is `-1`, which means the key expands to the available space not already used by other keys (e.g. the space bar)
   * `0` is interpreted as follows