新增键盘删除长按删除

CustomKeyboard/View/KBKeyboardView.m

@@ -26,6 +26,11 @@ static const CGFloat kKBBackspaceClearLabelCornerRadius = 8.0;
 static const CGFloat kKBBackspaceClearLabelHeight = 26.0;
 static const CGFloat kKBBackspaceClearLabelPaddingX = 10.0;
 static const CGFloat kKBBackspaceClearLabelTopGap = 6.0;
+static const NSInteger kKBBackspaceClearBatchSize = 24;
+static const NSTimeInterval kKBBackspaceClearBatchInterval = 0.005;
+static const NSInteger kKBBackspaceClearMaxDeletes = 10000;
+static const NSInteger kKBBackspaceClearEmptyContextMaxRounds = 40;
+static const NSInteger kKBBackspaceClearMaxStep = 80;
 
 static const NSTimeInterval kKBPreviewShowDuration = 0.08;
 static const NSTimeInterval kKBPreviewHideDuration = 0.06;
@@ -56,6 +61,10 @@ typedef NS_ENUM(NSInteger, KBBackspaceChunkClass) {
 @property (nonatomic, assign) NSTimeInterval backspaceHoldStartTime;
 @property (nonatomic, assign) BOOL backspaceChunkModeActive;
 @property (nonatomic, assign) BOOL backspaceClearHighlighted;
+@property (nonatomic, assign) NSUInteger backspaceHoldToken;
+@property (nonatomic, assign) BOOL backspaceHasLastTouchPoint;
+@property (nonatomic, assign) CGPoint backspaceLastTouchPointInSelf;
+@property (nonatomic, assign) NSUInteger backspaceClearToken;
 @property (nonatomic, weak) KBKeyButton *backspaceButton;
 @property (nonatomic, strong) UILabel *backspaceClearLabel;
 @property (nonatomic, strong) KBKeyPreviewView *previewView;
@@ -696,14 +705,22 @@ edgeSpacerMultiplier:(CGFloat)edgeSpacerMultiplier {
 
 // 长按退格：先连续单删，稍后切换为按段删除；松手停止。（不使用 NSTimer/DisplayLink）
 - (void)onBackspaceLongPress:(UILongPressGestureRecognizer *)gr {
+    if (gr) {
+        self.backspaceLastTouchPointInSelf = [gr locationInView:self];
+        self.backspaceHasLastTouchPoint = YES;
+    }
     switch (gr.state) {
         case UIGestureRecognizerStateBegan: {
+            // 递增 token：使上一次长按（可能尚未触发的 dispatch_after）立即失效，
+            // 避免“第一次长按后第二次长按失效/异常加速”等并发问题。
+            self.backspaceHoldToken += 1;
+            NSUInteger token = self.backspaceHoldToken;
             self.backspaceHoldActive = YES;
             self.backspaceHoldStartTime = [NSDate date].timeIntervalSinceReferenceDate;
             self.backspaceChunkModeActive = NO;
             [self kb_setBackspaceClearHighlighted:NO];
             [self kb_hideBackspaceClearLabel];
-            [self kb_backspaceStep];
+            [self kb_backspaceStepForToken:token];
         } break;
         case UIGestureRecognizerStateChanged: {
             [self kb_handleBackspaceLongPressChanged:gr];
@@ -720,15 +737,18 @@ edgeSpacerMultiplier:(CGFloat)edgeSpacerMultiplier {
 #pragma mark - Helpers
 
 // 单步删除并在需要时安排下一次，直到松手或无内容
-- (void)kb_backspaceStep {
+- (void)kb_backspaceStepForToken:(NSUInteger)token {
     if (!self.backspaceHoldActive) { return; }
+    if (token != self.backspaceHoldToken) { return; }
     UIInputViewController *ivc = KBFindInputViewController(self);
     if (!ivc) { self.backspaceHoldActive = NO; return; }
     id<UITextDocumentProxy> proxy = ivc.textDocumentProxy;
     NSString *before = proxy.documentContextBeforeInput ?: @"";
-    if (before.length <= 0) { self.backspaceHoldActive = NO; return; }
     NSTimeInterval elapsed = [NSDate date].timeIntervalSinceReferenceDate - self.backspaceHoldStartTime;
-    NSInteger deleteCount = [self kb_backspaceDeleteCountForContext:before elapsed:elapsed];
+    NSInteger deleteCount = 1;
+    if (before.length > 0) {
+        deleteCount = [self kb_backspaceDeleteCountForContext:before elapsed:elapsed];
+    }
     if (!self.backspaceChunkModeActive && elapsed >= kKBBackspaceChunkStartDelay) {
         self.backspaceChunkModeActive = YES;
         [self kb_showBackspaceClearLabelIfNeeded];
@@ -743,7 +763,7 @@ edgeSpacerMultiplier:(CGFloat)edgeSpacerMultiplier {
                                  (int64_t)(interval * NSEC_PER_SEC)),
                    dispatch_get_main_queue(), ^{
         __strong typeof(weakSelf) selfStrong = weakSelf;
-        [selfStrong kb_backspaceStep];
+        [selfStrong kb_backspaceStepForToken:token];
     });
 }
 
@@ -808,24 +828,86 @@ edgeSpacerMultiplier:(CGFloat)edgeSpacerMultiplier {
     return MAX(deleteCount, 1);
 }
 
+- (NSInteger)kb_clearDeleteCountForContext:(NSString *)context
+                               hitBoundary:(BOOL *)hitBoundary {
+    if (context.length == 0) { return kKBBackspaceClearBatchSize; }
+
+    static NSCharacterSet *sentenceBoundarySet = nil;
+    static NSCharacterSet *whitespaceSet = nil;
+    static dispatch_once_t onceToken;
+    dispatch_once(&onceToken, ^{
+        sentenceBoundarySet = [NSCharacterSet characterSetWithCharactersInString:@".!?;。！？；…\n"];
+        whitespaceSet = [NSCharacterSet whitespaceAndNewlineCharacterSet];
+    });
+
+    NSInteger length = context.length;
+    NSInteger end = length;
+    while (end > 0) {
+        unichar ch = [context characterAtIndex:end - 1];
+        if ([whitespaceSet characterIsMember:ch]) {
+            end -= 1;
+        } else {
+            break;
+        }
+    }
+    NSInteger searchEnd = end;
+    while (searchEnd > 0) {
+        unichar ch = [context characterAtIndex:searchEnd - 1];
+        if ([sentenceBoundarySet characterIsMember:ch]) {
+            searchEnd -= 1;
+        } else {
+            break;
+        }
+    }
+
+    NSInteger boundaryIndex = NSNotFound;
+    for (NSInteger i = searchEnd - 1; i >= 0; i--) {
+        unichar ch = [context characterAtIndex:i];
+        if ([sentenceBoundarySet characterIsMember:ch]) {
+            boundaryIndex = i;
+            break;
+        }
+    }
+
+    BOOL boundaryFound = (boundaryIndex != NSNotFound);
+    NSInteger deleteCount = length;
+    if (boundaryIndex != NSNotFound) {
+        deleteCount = length - (boundaryIndex + 1);
+    }
+    deleteCount = MAX(deleteCount, 1);
+    if (hitBoundary) {
+        *hitBoundary = boundaryFound;
+    }
+    return MIN(deleteCount, kKBBackspaceClearMaxStep);
+}
+
 - (void)kb_handleBackspaceLongPressChanged:(UILongPressGestureRecognizer *)gr {
     if (!self.backspaceHoldActive) { return; }
     NSTimeInterval elapsed = [NSDate date].timeIntervalSinceReferenceDate - self.backspaceHoldStartTime;
     if (elapsed < kKBBackspaceChunkStartDelay) { return; }
     [self kb_showBackspaceClearLabelIfNeeded];
     CGPoint point = [gr locationInView:self];
+    self.backspaceLastTouchPointInSelf = point;
+    self.backspaceHasLastTouchPoint = YES;
     BOOL inside = [self kb_isPointInsideBackspaceClearLabel:point];
     [self kb_setBackspaceClearHighlighted:inside];
 }
 
 - (void)kb_handleBackspaceLongPressEnded:(UILongPressGestureRecognizer *)gr {
     BOOL shouldClear = self.backspaceClearHighlighted;
-    if (!shouldClear && gr) {
+    if (!shouldClear) {
-        CGPoint point = [gr locationInView:self];
+        CGPoint point = CGPointZero;
+        if (gr) {
+            point = [gr locationInView:self];
+        } else if (self.backspaceHasLastTouchPoint) {
+            point = self.backspaceLastTouchPointInSelf;
+        }
         shouldClear = [self kb_isPointInsideBackspaceClearLabel:point];
     }
     self.backspaceHoldActive = NO;
     self.backspaceChunkModeActive = NO;
+    self.backspaceHoldToken += 1; // 结束/取消时也使剩余回调失效
+    self.backspaceHasLastTouchPoint = NO;
     [self kb_hideBackspaceClearLabel];
     if (shouldClear) {
         [self kb_clearAllInput];
@@ -876,8 +958,9 @@ edgeSpacerMultiplier:(CGFloat)edgeSpacerMultiplier {
 
 - (BOOL)kb_isPointInsideBackspaceClearLabel:(CGPoint)point {
     if (!self.backspaceClearLabel || self.backspaceClearLabel.hidden) { return NO; }
-    [self layoutIfNeeded];
+    [self kb_updateBackspaceClearLabelFrame];
-    return CGRectContainsPoint(self.backspaceClearLabel.frame, point);
+    CGRect hitFrame = CGRectInset(self.backspaceClearLabel.frame, -12.0, -10.0);
+    return CGRectContainsPoint(hitFrame, point);
 }
 
 - (void)kb_setBackspaceClearHighlighted:(BOOL)highlighted {
@@ -922,19 +1005,61 @@ edgeSpacerMultiplier:(CGFloat)edgeSpacerMultiplier {
 }
 
 - (void)kb_clearAllInput {
+    self.backspaceClearToken += 1;
+    NSUInteger token = self.backspaceClearToken;
+    [self kb_clearAllInputStepForToken:token guard:0 emptyRounds:0];
+}
+
+- (void)kb_clearAllInputStepForToken:(NSUInteger)token
+                               guard:(NSInteger)guard
+                         emptyRounds:(NSInteger)emptyRounds {
+    if (token != self.backspaceClearToken) { return; }
     UIInputViewController *ivc = KBFindInputViewController(self);
     if (!ivc) { return; }
     id<UITextDocumentProxy> proxy = ivc.textDocumentProxy;
-    NSInteger guard = 0; // 上限保护，避免极端情况下长时间阻塞
-    while (guard < 10000) {
     NSString *before = proxy.documentContextBeforeInput ?: @"";
     NSInteger count = before.length;
-        if (count <= 0) { break; }
+    NSInteger batch = 0;
-        for (NSInteger i = 0; i < count; i++) {
+    NSInteger nextEmptyRounds = emptyRounds;
+    BOOL hitBoundary = NO;
+    if (count > 0) {
+        batch = [self kb_clearDeleteCountForContext:before hitBoundary:&hitBoundary];
+        nextEmptyRounds = 0;
+    } else {
+        batch = kKBBackspaceClearBatchSize;
+        nextEmptyRounds = emptyRounds + 1;
+    }
+    if (batch <= 0) { batch = 1; }
+
+    if (guard >= kKBBackspaceClearMaxDeletes ||
+        nextEmptyRounds > kKBBackspaceClearEmptyContextMaxRounds) {
+        return;
+    }
+
+    for (NSInteger i = 0; i < batch; i++) {
         [proxy deleteBackward];
     }
-        guard += count;
+
+    NSInteger nextGuard = guard + batch;
+    BOOL shouldContinue = NO;
+    if (count > 0 && !hitBoundary) {
+        if (count > batch) {
+            shouldContinue = YES;
+        } else if ([proxy hasText]) {
+            shouldContinue = YES;
         }
+    }
+
+    if (!shouldContinue) { return; }
+    __weak typeof(self) weakSelf = self;
+    dispatch_after(dispatch_time(DISPATCH_TIME_NOW,
+                                 (int64_t)(kKBBackspaceClearBatchInterval * NSEC_PER_SEC)),
+                   dispatch_get_main_queue(), ^{
+        __strong typeof(weakSelf) selfStrong = weakSelf;
+        [selfStrong kb_clearAllInputStepForToken:token
+                                           guard:nextGuard
+                                     emptyRounds:nextEmptyRounds];
+    });
 }
 
 #pragma mark - Layout