fixed Backspace swiping for the 3rd time with stricter checks for pressing

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

@@ -89,6 +89,7 @@ public class SoftKey extends androidx.appcompat.widget.AppCompatButton implement
 		} else if (action == MotionEvent.ACTION_UP) {
 			if (!repeat || hold) {
 				hold = false;
+				repeat = false;
 				boolean result = handleRelease();
 				lastPressedKey = ignoreLastPressedKey ? -1 : getId();
 				return result;

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

@@ -12,8 +12,11 @@ import io.github.sspanak.tt9.ui.Vibration;
 
 public class SoftKeyBackspace extends SwipeableKey {
 	private int repeat = 0;
+
+	private boolean isActionPerformed = false;
 	private final Handler waitForSwipe = new Handler();
 
+
 	public SoftKeyBackspace(Context context) {
 		super(context);
 	}
@@ -63,20 +66,36 @@ public class SoftKeyBackspace extends SwipeableKey {
 	@Override
 	final protected boolean handlePress() {
 		super.handlePress();
-		waitForSwipe.postDelayed(this::handlePressDebounced, 15);
+		isActionPerformed = false;
+		waitForSwipe.postDelayed(this::handlePressDebounced, 1 + getAverageSwipeProcessingTime());
 		return true;
 	}
 
 
+	/**
+	 * Avoids deleting text twice when swiping - first, when the user touches the screen, and then,
+	 * when they finish the swipe gesture.
+	 */
 	private void handlePressDebounced() {
-		if (notSwiped()) {
+		if (!isActionPerformed) {
+			isActionPerformed = true;
 			deleteText();
 		}
 	}
 
 
+	@Override
+	protected void handleStartSwipeX(float position, float delta) {
+		if (!isActionPerformed && validateTT9Handler()) {
+			isActionPerformed = true;
+			tt9.onBackspace(SettingsStore.BACKSPACE_ACCELERATION_REPEAT_DEBOUNCE);
+		}
+	}
+
+
 	@Override
 	final protected void handleHold() {
+		isActionPerformed = true;
 		repeat++;
 		deleteText();
 	}
@@ -86,24 +105,11 @@ public class SoftKeyBackspace extends SwipeableKey {
 	final protected boolean handleRelease() {
 		vibrate(repeat > 0 ? Vibration.getReleaseVibration() : Vibration.getNoVibration());
 		repeat = 0;
+
 		return true;
 	}
 
 
-	@Override
-	protected void handleStartSwipeX(float position, float delta) {
-		waitForSwipe.removeCallbacksAndMessages(null);
-	}
-
-
-	@Override
-	protected void handleEndSwipeX(float position, float delta) {
-		if (validateTT9Handler()) {
-			tt9.onBackspace(SettingsStore.BACKSPACE_ACCELERATION_REPEAT_DEBOUNCE);
-		}
-	}
-
-
 	private void deleteText() {
 		if (validateTT9Handler() && !tt9.onBackspace(repeat)) {
 			// Limited or special numeric field (e.g. formatted money or dates) cannot always return

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

@@ -7,8 +7,11 @@ import android.view.View;
 
 import io.github.sspanak.tt9.R;
 import io.github.sspanak.tt9.preferences.settings.SettingsStore;
+import io.github.sspanak.tt9.util.Timer;
 
 abstract public class SwipeableKey extends SoftKey {
+	private static final String LOG_TAG = SwipeableKey.class.getSimpleName();
+
 	private float HOLD_DURATION_THRESHOLD;
 	protected float SWIPE_X_THRESHOLD;
 	protected float SWIPE_Y_THRESHOLD;
@@ -22,6 +25,10 @@ abstract public class SwipeableKey extends SoftKey {
 	private float startY;
 	private long startTime;
 
+	private int swipeCount = 0;
+	private long swipeProcessingTime = 0;
+	private long swipeProcessingTimeAverage = 40;
+
 
 	public SwipeableKey(Context context) {
 		super(context);
@@ -53,10 +60,31 @@ abstract public class SwipeableKey extends SoftKey {
 	protected float getSwipeYThreshold(Context context) { return context.getResources().getDimensionPixelSize(R.dimen.numpad_key_height) / 10.0f; }
 
 
+	private void updateSwipeTimingStats() {
+		long time = Timer.get(LOG_TAG);
+
+		long deltaT = time - swipeProcessingTimeAverage;
+		if (deltaT < -swipeProcessingTimeAverage || deltaT > 5) {
+			swipeCount = 0;
+			swipeProcessingTime = 0;
+		}
+
+		swipeCount++;
+		swipeProcessingTime += time;
+		swipeProcessingTimeAverage = swipeProcessingTime / swipeCount;
+	}
+
+
+	protected long getAverageSwipeProcessingTime() {
+		return swipeProcessingTimeAverage;
+	}
+
+
 	@Override
 	public boolean onTouch(View v, MotionEvent event) {
 		switch(event.getAction() & MotionEvent.ACTION_MASK) {
 			case MotionEvent.ACTION_DOWN:
+				Timer.start(LOG_TAG);
 				onPress(event);
 				break;
 			case MotionEvent.ACTION_MOVE:
@@ -107,9 +135,11 @@ abstract public class SwipeableKey extends SoftKey {
 			handleSwipeX(event.getRawX(), deltaX);
 		} else if (Math.abs(deltaY) >= SWIPE_Y_THRESHOLD) {
 			isSwipingY = true;
+			updateSwipeTimingStats();
 			handleStartSwipeY(event.getRawY(), deltaY);
 		} else if (Math.abs(deltaX) >= SWIPE_X_THRESHOLD) {
 			isSwipingX = true;
+			updateSwipeTimingStats();
 			handleStartSwipeX(event.getRawX(), deltaX);
 		} else if (!isHolding && Math.abs(deltaX) < SWIPE_X_THRESHOLD && Math.abs(deltaY) < SWIPE_Y_THRESHOLD) {
 			onLongClick(v);