combining characters are now displayed with an empty-circle base for better readability

app/src/main/java/io/github/sspanak/tt9/ui/main/keys/SoftKeyNumber2to9.java

@@ -15,6 +15,7 @@ import io.github.sspanak.tt9.languages.LanguageKind;
 import io.github.sspanak.tt9.preferences.settings.SettingsStore;
 import io.github.sspanak.tt9.util.Logger;
 import io.github.sspanak.tt9.util.TextTools;
+import io.github.sspanak.tt9.util.chars.Characters;
 
 public class SoftKeyNumber2to9 extends SoftKeyNumber {
 	public SoftKeyNumber2to9(Context context) { super(context); }
@@ -88,16 +89,17 @@ public class SoftKeyNumber2to9 extends SoftKeyNumber {
 	 * In some languages there are many characters for a single key. Naturally, they can not all fit
 	 * on one key. As suggested by the community, we could display them as "A-Z".
 	 * @see <a href="https://github.com/sspanak/tt9/issues/628">Issue #628</a>
+	 * Additionally, for combining characters, we want to add a dummy base, to ensure they look properly.
 	 */
 	private String abbreviateCharList(String chars, Locale locale, boolean isUppercase) {
 		String firstLetter = chars.substring(0, 1);
-		String lastLetter = chars.substring(chars.length() - 1);
+		firstLetter = TextTools.isCombining(firstLetter) ? Characters.COMBINING_ZERO_BASE + firstLetter : firstLetter;
-		boolean containsCombiningChars = TextTools.isCombining(firstLetter) || TextTools.isCombining(lastLetter);
 
-		return
+		String lastLetter = chars.substring(chars.length() - 1);
-			(isUppercase ? firstLetter.toUpperCase(locale) : firstLetter)
+		lastLetter = TextTools.isCombining(lastLetter) ? Characters.COMBINING_ZERO_BASE + lastLetter : lastLetter;
-			+ (containsCombiningChars ? "–  " : "–")
+
-			+ (isUppercase ? lastLetter.toUpperCase(locale) : lastLetter);
+		String list = firstLetter + "–" + lastLetter;
+		return isUppercase ? list.toUpperCase(locale) : list;
 	}
 
 

app/src/main/java/io/github/sspanak/tt9/ui/tray/SuggestionsBar.java

@@ -22,6 +22,7 @@ import io.github.sspanak.tt9.R;
 import io.github.sspanak.tt9.preferences.settings.SettingsStore;
 import io.github.sspanak.tt9.ui.Vibration;
 import io.github.sspanak.tt9.ui.main.ResizableMainView;
+import io.github.sspanak.tt9.util.TextTools;
 import io.github.sspanak.tt9.util.chars.Characters;
 
 public class SuggestionsBar {
@@ -141,19 +142,24 @@ public class SuggestionsBar {
 
 		String suggestion = suggestions.get(id);
 
-		if (suggestion.endsWith(STEM_SUFFIX)) {
+		if (Characters.ZWJ_GRAPHIC.equals(suggestion)) return Characters.ZWJ;
-			return stem;
+		if (Characters.ZWNJ_GRAPHIC.equals(suggestion)) return Characters.ZWNJ;
-		} else if (suggestion.startsWith(STEM_VARIATION_PREFIX)) {
+		if (suggestion.equals(Characters.NEW_LINE)) return "\n";
-			return stem + suggestion.substring(STEM_VARIATION_PREFIX.length());
+
-		} else if (suggestion.startsWith(STEM_PUNCTUATION_VARIATION_PREFIX)) {
+		int endIndex = suggestion.indexOf(STEM_SUFFIX);
-			return stem + suggestion.substring(STEM_PUNCTUATION_VARIATION_PREFIX.length());
+		endIndex = endIndex == -1 ? suggestion.length() : endIndex;
+
+		int startIndex = 0;
+		String[] prefixes = {STEM_VARIATION_PREFIX, STEM_PUNCTUATION_VARIATION_PREFIX, Characters.COMBINING_ZERO_BASE};
+    for (String prefix : prefixes) {
+			startIndex = Math.max(startIndex, suggestion.indexOf(prefix) + 1);
+    }
+
+		if (startIndex == 0 && endIndex == suggestion.length()) {
+			return suggestion;
 		}
 
-		return switch (suggestion) {
+		return stem + suggestion.substring(startIndex, endIndex);
-			case Characters.ZWJ_GRAPHIC -> Characters.ZWJ;
-			case Characters.ZWNJ_GRAPHIC -> Characters.ZWNJ;
-			default -> suggestion.equals(Characters.NEW_LINE) ? "\n" : suggestion;
-		};
 	}
 
 
@@ -232,6 +238,10 @@ public class SuggestionsBar {
 
 
 	private String formatUnreadableSuggestion(String suggestion) {
+		if (TextTools.isCombining(suggestion)) {
+			return Characters.COMBINING_ZERO_BASE + suggestion;
+		}
+
 		return switch (suggestion) {
 			case "\n" -> Characters.NEW_LINE;
 			case Characters.ZWJ -> Characters.ZWJ_GRAPHIC;

app/src/main/java/io/github/sspanak/tt9/util/chars/Characters.java

@@ -6,6 +6,8 @@ import java.util.Arrays;
 import io.github.sspanak.tt9.languages.Language;
 
 public class Characters extends Emoji {
+	public static final String COMBINING_ZERO_BASE = "◌";
+
 	final public static ArrayList<String> Currency = new ArrayList<>(Arrays.asList(
 		"$", "€", "₿", "¢", "¤", "₱", "¥", "£"
 	));