Add source-key action target slides

CHANGELOG.md

@@ -14,6 +14,10 @@ and this project uses [Semantic Versioning](https://semver.org/spec/v2.0.0.html)
 
 ## [Unreleased]
 
+### Added
+- **Source-key action targets** — slide from the Enter/action key into a temporary action target
+  panel for existing actions like `JOIN_NEXT`, `FORCE_NEXT_SPACE`, and `UNDO_WORD`. (#37)
+
 ## [3.9.1] - 2026-06-11
 
 ### Fixed

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

@@ -684,6 +684,19 @@ private PopupKeysPanel showPopupKeysKeyboard(@NonNull final Key key,
         return popupKeysKeyboardView;
     }
 
+    @Override
+    @Nullable
+    public PopupKeysPanel showSourceKeyActionKeyboard(@NonNull final Key key,
+            @NonNull final PointerTracker tracker, @NonNull final PopupKeySpec[] popupKeys) {
+        if (popupKeys.length == 0) {
+            return null;
+        }
+        final Key popupParentKey = Key.copyWithShortcutPopupKeys(key, popupKeys);
+        final int fixedKeyWidth = popupKeys.length > 0 ? key.getWidth() : 0;
+        return showPopupKeysKeyboard(popupParentKey, tracker, false,
+                PopupKeysKeyboardView.NO_ROW_ALIGN, fixedKeyWidth);
+    }
+
     @Override
     @Nullable
     public PopupKeysPanel showShortcutRowKeyboard(@NonNull final Key key,

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

@@ -28,6 +28,7 @@
 import helium314.keyboard.keyboard.internal.GestureStrokeRecognitionParams;
 import helium314.keyboard.keyboard.internal.PointerTrackerQueue;
 import helium314.keyboard.keyboard.internal.TimerProxy;
+import helium314.keyboard.keyboard.internal.PopupKeySpec;
 import helium314.keyboard.keyboard.internal.TypingTimeRecorder;
 import helium314.keyboard.keyboard.internal.keyboard_parser.floris.KeyCode;
 import helium314.keyboard.latin.R;
@@ -40,6 +41,7 @@
 import helium314.keyboard.latin.utils.KtxKt;
 import helium314.keyboard.latin.utils.LayoutType;
 import helium314.keyboard.latin.utils.Log;
+import helium314.keyboard.latin.utils.SourceKeyActionTargets;
 
 import java.util.ArrayList;
 import java.util.Locale;
@@ -215,6 +217,8 @@ public static int consumeGestureSeedCodepoint() {
     private boolean mShortcutBottomRowSwipeAllowed = false;
     private boolean mInShortcutRowSwipe = false;
     private static boolean sInShortcutRowSwipe = false;
+    private boolean mSourceKeyActionAllowed = false;
+    private boolean mInSourceKeyAction = false;
 
     // Touchpad mode for cursor control
     public static boolean sPersistentTouchpadModeActive = false;
@@ -969,6 +973,7 @@ private void dismissPopupKeysPanel() {
             mInShortcutRowSwipe = false;
             sInShortcutRowSwipe = false;
         }
+        mInSourceKeyAction = false;
     }
 
     private void onDownEventInternal(final int x, final int y, final long eventTime) {
@@ -987,6 +992,10 @@ private void onDownEventInternal(final int x, final int y, final long eventTime)
             mKeySwipeAllowed = true;
             sInKeySwipe = true;
         }
+        mSourceKeyActionAllowed = key != null && !sInGesture && !mKeySwipeAllowed
+                && SourceKeyActionTargets.hasTargetsForSource(
+                        key.getCode(), Settings.getValues().mSourceKeyActionTargets);
+        mInSourceKeyAction = false;
         mShortcutTopRowSwipeAllowed = isShortcutRowSource(key, true);
         mShortcutBottomRowSwipeAllowed = isShortcutRowSource(key, false);
         mInShortcutRowSwipe = false;
@@ -1340,6 +1349,37 @@ private void onKeySwipe(final int code, final int x, final int y, final long eve
         }
     }
 
+    private boolean tryStartSourceKeyAction(final int x, final int y, final long eventTime) {
+        if (!mSourceKeyActionAllowed || mInSourceKeyAction || isShowingPopupKeysPanel()
+                || sInGesture || mCurrentKey == null) {
+            return mInSourceKeyAction;
+        }
+        final int dX = x - mStartX;
+        final int dY = y - mStartY;
+        if (abs(dX) < sPointerStep && abs(dY) < sPointerStep) {
+            return false;
+        }
+        final PopupKeySpec[] popupKeys = SourceKeyActionTargets.popupKeysForSource(
+                mCurrentKey.getCode(), Settings.getValues().mSourceKeyActionTargets, Locale.getDefault());
+        if (popupKeys == null || popupKeys.length == 0) {
+            return false;
+        }
+        final PopupKeysPanel popupKeysPanel = sDrawingProxy.showSourceKeyActionKeyboard(
+                mCurrentKey, this, popupKeys);
+        if (popupKeysPanel == null) {
+            return false;
+        }
+        sTimerProxy.cancelKeyTimersOf(this);
+        mIsDetectingGesture = false;
+        setReleasedKeyGraphics(mCurrentKey, true);
+        final int translatedX = popupKeysPanel.translateX(x);
+        final int translatedY = popupKeysPanel.translateY(y);
+        popupKeysPanel.onDownEvent(translatedX, translatedY, mPointerId, eventTime);
+        mPopupKeysPanel = popupKeysPanel;
+        mInSourceKeyAction = true;
+        return true;
+    }
+
     private boolean isShortcutRowSource(final Key key, final boolean topRow) {
         final SettingsValues sv = Settings.getValues();
         if (!sv.mShortcutRowsEnabled
@@ -1409,6 +1449,9 @@ private void onMoveEventInternal(final int x, final int y, final long eventTime)
             onKeySwipe(oldKey.getCode(), x, y, eventTime);
             return;
         }
+        if (tryStartSourceKeyAction(x, y, eventTime)) {
+            return;
+        }
 
         final Key newKey = onMoveKey(x, y);
         final int lastX = mLastX;

app/src/main/java/helium314/keyboard/keyboard/internal/DrawingProxy.java

@@ -42,6 +42,10 @@ public interface DrawingProxy {
     PopupKeysPanel showShortcutRowKeyboard(@NonNull Key key, @NonNull PointerTracker tracker,
             @NonNull LayoutType layoutType, boolean belowSourceKey);
 
+    @Nullable
+    PopupKeysPanel showSourceKeyActionKeyboard(@NonNull Key key, @NonNull PointerTracker tracker,
+            @NonNull PopupKeySpec[] popupKeys);
+
     /**
      * Start a while-typing-animation.
      * @param fadeInOrOut {@link #FADE_IN} starts while-typing-fade-in animation.

app/src/main/java/helium314/keyboard/latin/settings/Defaults.kt

@@ -181,6 +181,7 @@ object Defaults {
     const val PREF_MORE_POPUP_KEYS = "main"
     const val PREF_SPACE_TO_CHANGE_LANG = true
     const val PREF_LANGUAGE_SWIPE_DISTANCE = 5
+    const val PREF_SOURCE_KEY_ACTION_TARGETS = "ACTION=JOIN_NEXT,FORCE_NEXT_SPACE,UNDO_WORD"
     const val PREF_TOUCHPAD_SENSITIVITY = 50
     const val PREF_TOUCHPAD_EDGE_SCROLL = false
     const val PREF_FORCE_AUTO_CAPS = false

app/src/main/java/helium314/keyboard/latin/settings/Settings.java

@@ -214,6 +214,7 @@ public final class Settings implements SharedPreferences.OnSharedPreferenceChang
 
     public static final String PREF_SPACE_TO_CHANGE_LANG = "prefs_long_press_keyboard_to_change_lang";
     public static final String PREF_LANGUAGE_SWIPE_DISTANCE = "language_swipe_distance";
+    public static final String PREF_SOURCE_KEY_ACTION_TARGETS = "source_key_action_targets";
     public static final String PREF_TOUCHPAD_SENSITIVITY = "touchpad_sensitivity";
     public static final String PREF_TOUCHPAD_EDGE_SCROLL = "touchpad_edge_scroll";
     public static final String PREF_PERSIST_FLOATING_KEYBOARD = "persist_floating_keyboard";

app/src/main/java/helium314/keyboard/latin/settings/SettingsValues.java

@@ -81,6 +81,7 @@ public class SettingsValues {
         public final int mSpaceSwipeHorizontal;
         public final int mSpaceSwipeVertical;
         public final int mLanguageSwipeDistance;
+        public final String mSourceKeyActionTargets;
         public final int mTouchpadSensitivity;
         public final boolean mTouchpadEdgeScroll;
         public final boolean mForceAutoCaps;
@@ -435,6 +436,8 @@ public SettingsValues(final Context context, final SharedPreferences prefs, fina
                 mSpaceSwipeVertical = Settings.readVerticalSpaceSwipe(prefs);
                 mLanguageSwipeDistance = prefs.getInt(Settings.PREF_LANGUAGE_SWIPE_DISTANCE,
                                 Defaults.PREF_LANGUAGE_SWIPE_DISTANCE);
+                mSourceKeyActionTargets = prefs.getString(Settings.PREF_SOURCE_KEY_ACTION_TARGETS,
+                                Defaults.PREF_SOURCE_KEY_ACTION_TARGETS);
                 mTouchpadSensitivity = prefs.getInt(Settings.PREF_TOUCHPAD_SENSITIVITY,
                                 Defaults.PREF_TOUCHPAD_SENSITIVITY);
                 mTouchpadEdgeScroll = prefs.getBoolean(Settings.PREF_TOUCHPAD_EDGE_SCROLL,

app/src/main/java/helium314/keyboard/latin/utils/SourceKeyActionTargets.kt

@@ -0,0 +1,79 @@
+package helium314.keyboard.latin.utils
+
+import helium314.keyboard.keyboard.internal.KeyboardIconsSet
+import helium314.keyboard.keyboard.internal.KeyboardCodesSet
+import helium314.keyboard.keyboard.internal.PopupKeySpec
+import helium314.keyboard.keyboard.internal.keyboard_parser.floris.KeyCode
+import helium314.keyboard.latin.common.Constants
+import java.util.EnumMap
+import java.util.Locale
+
+object SourceKeyActionTargets {
+    enum class SourceKey { ACTION_KEY, PERIOD, COMMA }
+
+    private var cachedSpec: String? = null
+    private var cachedTargets: Map<SourceKey, List<ToolbarKey>> = emptyMap()
+
+    @JvmStatic
+    fun hasTargetsForSource(code: Int, spec: String): Boolean {
+        val source = sourceKeyForCode(code) ?: return false
+        return targets(spec)[source]?.isNotEmpty() == true
+    }
+
+    @JvmStatic
+    fun popupKeysForSource(code: Int, spec: String, locale: Locale): Array<PopupKeySpec>? {
+        val source = sourceKeyForCode(code) ?: return null
+        val keys = targets(spec)[source].orEmpty()
+        if (keys.isEmpty()) return null
+        return keys.map { toolbarKey ->
+            val keyName = toolbarKeyStrings[toolbarKey] ?: toolbarKey.name.lowercase(Locale.US)
+            PopupKeySpec(
+                "${KeyboardIconsSet.PREFIX_ICON}$keyName|${KeyboardCodesSet.PREFIX_CODE}${getCodeForToolbarKey(toolbarKey)}",
+                false,
+                locale,
+            )
+        }.toTypedArray()
+    }
+
+    fun parse(spec: String): Map<SourceKey, List<ToolbarKey>> = targets(spec)
+
+    @JvmStatic
+    fun clearCache() {
+        cachedSpec = null
+        cachedTargets = emptyMap()
+    }
+
+    private fun targets(spec: String): Map<SourceKey, List<ToolbarKey>> {
+        if (spec == cachedSpec) return cachedTargets
+        val parsed = EnumMap<SourceKey, MutableList<ToolbarKey>>(SourceKey::class.java)
+        spec.split(';').forEach { entry ->
+            val trimmed = entry.trim()
+            if (trimmed.isEmpty()) return@forEach
+            val source = sourceKeyForName(trimmed.substringBefore('=', missingDelimiterValue = "")) ?: return@forEach
+            val actions = trimmed.substringAfter('=', missingDelimiterValue = "")
+                .split(',')
+                .mapNotNull { it.enumValueOrNull<ToolbarKey>() }
+            if (actions.isNotEmpty()) parsed[source] = actions.toMutableList()
+        }
+        cachedSpec = spec
+        cachedTargets = parsed
+        return cachedTargets
+    }
+
+    private fun sourceKeyForName(name: String): SourceKey? = when (name.trim().uppercase()) {
+        "ACTION", "ACTION_KEY", "ENTER" -> SourceKey.ACTION_KEY
+        "PERIOD", "." -> SourceKey.PERIOD
+        "COMMA", "," -> SourceKey.COMMA
+        else -> null
+    }
+
+    private fun sourceKeyForCode(code: Int): SourceKey? = when (code) {
+        Constants.CODE_ENTER, KeyCode.SHIFT_ENTER, KeyCode.ACTION_NEXT, KeyCode.ACTION_PREVIOUS -> SourceKey.ACTION_KEY
+        Constants.CODE_PERIOD -> SourceKey.PERIOD
+        ','.code -> SourceKey.COMMA
+        else -> null
+    }
+
+    private inline fun <reified T : Enum<T>> String.enumValueOrNull(): T? =
+        runCatching { enumValueOf<T>(trim().uppercase()) }.getOrNull()
+}

app/src/main/java/helium314/keyboard/settings/screens/AdvancedScreen.kt

@@ -89,6 +89,7 @@ fun AdvancedSettingsScreen(
             || Settings.readVerticalSpaceSwipe(prefs) == KeyboardActionListener.SWIPE_SWITCH_LANGUAGE)
             Settings.PREF_LANGUAGE_SWIPE_DISTANCE else null,
         Settings.PREF_SPACE_TO_CHANGE_LANG,
+        Settings.PREF_SOURCE_KEY_ACTION_TARGETS,
         Settings.PREFS_LONG_PRESS_SYMBOLS_FOR_NUMPAD,
         Settings.PREF_ENABLE_EMOJI_ALT_PHYSICAL_KEY,
         if (Build.VERSION.SDK_INT < Build.VERSION_CODES.Q) Settings.PREF_SHOW_SETUP_WIZARD_ICON else null,
@@ -195,6 +196,26 @@ fun createAdvancedSettings(context: Context) = listOfNotNull(
             )
         }
     },
+    Setting(context, Settings.PREF_SOURCE_KEY_ACTION_TARGETS, R.string.source_key_action_targets, R.string.source_key_action_targets_summary) { setting ->
+        var showDialog by rememberSaveable { mutableStateOf(false) }
+        Preference(
+            name = setting.title,
+            description = setting.description,
+            onClick = { showDialog = true }
+        )
+        if (showDialog) {
+            val prefs = LocalContext.current.prefs()
+            TextInputDialog(
+                onDismissRequest = { showDialog = false },
+                textInputLabel = { Text(stringResource(R.string.source_key_action_targets_hint)) },
+                initialText = prefs.getString(setting.key, Defaults.PREF_SOURCE_KEY_ACTION_TARGETS)!!,
+                onConfirmed = { prefs.edit { putString(setting.key, it) } },
+                title = { Text(stringResource(R.string.source_key_action_targets)) },
+                neutralButtonText = if (prefs.contains(setting.key)) stringResource(R.string.button_default) else null,
+                onNeutral = { prefs.edit { remove(setting.key) } },
+            )
+        }
+    },
     Setting(context, Settings.PREF_MORE_POPUP_KEYS, R.string.show_popup_keys_title) {
         val items = listOf(POPUP_KEYS_NORMAL, POPUP_KEYS_MAIN, POPUP_KEYS_MORE, POPUP_KEYS_ALL).map { setting ->
             stringResource(morePopupKeysResId(setting)) to setting

app/src/main/res/values/strings.xml

@@ -468,6 +468,12 @@
     <string name="show_popup_keys_all">Add all available variants</string>
     <!-- Preferences item for enabling URL detection -->
     <string name="url_detection_title">URL detection</string>
+    <!-- Preferences item for source-key action target layers -->
+    <string name="source_key_action_targets">Source-key action targets</string>
+    <!-- Description for "source_key_action_targets" setting -->
+    <string name="source_key_action_targets_summary">Slide from Enter, period, or comma to choose existing toolbar actions</string>
+    <!-- Input hint for "source_key_action_targets" setting -->
+    <string name="source_key_action_targets_hint">Example: ACTION=JOIN_NEXT,FORCE_NEXT_SPACE,UNDO_WORD;PERIOD=UNDO_WORD</string>
     <!-- Description for "url_detection_title" option. -->
     <string name="url_detection_summary">Try to detect URLs and similar as a single word</string>
     <!-- Preferences item for disabling word learning -->

app/src/test/java/helium314/keyboard/latin/utils/SourceKeyActionTargetsTest.kt

@@ -0,0 +1,81 @@
+package helium314.keyboard.latin.utils
+
+import android.content.Context
+import androidx.test.core.app.ApplicationProvider
+import helium314.keyboard.latin.settings.Settings
+import helium314.keyboard.latin.common.Constants
+import helium314.keyboard.latin.utils.SourceKeyActionTargets.SourceKey
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertFalse
+import org.junit.Assert.assertNotNull
+import org.junit.Assert.assertTrue
+import org.junit.Before
+import org.junit.runner.RunWith
+import org.robolectric.RobolectricTestRunner
+import org.robolectric.annotation.Config
+import org.junit.Test
+import java.util.Locale
+@RunWith(RobolectricTestRunner::class)
+@Config(sdk = [33])
+class SourceKeyActionTargetsTest {
+    @Before
+    fun setup() {
+        Settings.init(ApplicationProvider.getApplicationContext<Context>())
+        SourceKeyActionTargets.clearCache()
+    }
+    @Test
+    fun parseAcceptsTargetListsForSourceKeys() {
+        val targets = SourceKeyActionTargets.parse(
+            "ACTION=JOIN_NEXT,FORCE_NEXT_SPACE,UNDO_WORD;PERIOD=UNDO_WORD;COMMA=EMOJI,SETTINGS"
+        )
+
+        assertEquals(
+            listOf(ToolbarKey.JOIN_NEXT, ToolbarKey.FORCE_NEXT_SPACE, ToolbarKey.UNDO_WORD),
+            targets[SourceKey.ACTION_KEY],
+        )
+        assertEquals(listOf(ToolbarKey.UNDO_WORD), targets[SourceKey.PERIOD])
+        assertEquals(listOf(ToolbarKey.EMOJI, ToolbarKey.SETTINGS), targets[SourceKey.COMMA])
+    }
+
+    @Test
+    fun parseAcceptsUserFriendlySourceAliases() {
+        val targets = SourceKeyActionTargets.parse("ENTER=JOIN_NEXT;.=UNDO_WORD;,=FORCE_NEXT_SPACE")
+
+        assertEquals(listOf(ToolbarKey.JOIN_NEXT), targets[SourceKey.ACTION_KEY])
+        assertEquals(listOf(ToolbarKey.UNDO_WORD), targets[SourceKey.PERIOD])
+        assertEquals(listOf(ToolbarKey.FORCE_NEXT_SPACE), targets[SourceKey.COMMA])
+    }
+
+    @Test
+    fun parseSkipsMalformedEntriesAndUnknownActions() {
+        val targets = SourceKeyActionTargets.parse(
+            "ACTION=JOIN_NEXT,NO_SUCH_ACTION;BAD=JOIN_NEXT;PERIOD=NO_SUCH_ACTION;garbage"
+        )
+
+        assertEquals(mapOf(SourceKey.ACTION_KEY to listOf(ToolbarKey.JOIN_NEXT)), targets)
+    }
+
+    @Test
+    fun hasTargetsCanonicalizesSupportedSourceCodes() {
+        val spec = "ACTION=JOIN_NEXT;PERIOD=UNDO_WORD;COMMA=FORCE_NEXT_SPACE"
+
+        assertTrue(SourceKeyActionTargets.hasTargetsForSource(Constants.CODE_ENTER, spec))
+        assertTrue(SourceKeyActionTargets.hasTargetsForSource(Constants.CODE_PERIOD, spec))
+        assertTrue(SourceKeyActionTargets.hasTargetsForSource(','.code, spec))
+        assertFalse(SourceKeyActionTargets.hasTargetsForSource('a'.code, spec))
+    }
+
+    @Test
+    fun popupKeysResolveTargetsToExistingToolbarKeyCodes() {
+        val popupKeys = SourceKeyActionTargets.popupKeysForSource(
+            Constants.CODE_ENTER,
+            "ACTION=JOIN_NEXT,FORCE_NEXT_SPACE",
+            Locale.US,
+        )
+
+        assertNotNull(popupKeys)
+        assertEquals(2, popupKeys!!.size)
+        assertEquals(getCodeForToolbarKey(ToolbarKey.JOIN_NEXT), popupKeys[0].mCode)
+        assertEquals(getCodeForToolbarKey(ToolbarKey.FORCE_NEXT_SPACE), popupKeys[1].mCode)
+    }
+}