修改 我已经退出界面，然后从新进入界面弹起键盘，为什么撤销删除按钮显示？

CustomKeyboard/KeyboardViewController.m

@@ -65,6 +65,8 @@ static void KBSkinInstallNotificationCallback(CFNotificationCenterRef center,
 
 - (void)viewDidLoad {
     [super viewDidLoad];
+    // 撤销删除是“上一段删除操作”的临时状态；键盘被系统回收/重建或跨页面回来时应当清空，避免误显示。
+    [[KBBackspaceUndoManager shared] registerNonClearAction];
     [self setupUI];
     self.suggestionEngine = [KBSuggestionEngine shared];
     self.currentWord = @"";
@@ -93,11 +95,20 @@ static void KBSkinInstallNotificationCallback(CFNotificationCenterRef center,
 
 - (void)viewWillAppear:(BOOL)animated{
     [super viewWillAppear:animated];
+    // 进入/重新进入输入界面时，清理上一次会话残留的撤销状态与缓存，避免显示“撤销删除”但实际上已不可撤销。
+    [[KBBackspaceUndoManager shared] registerNonClearAction];
+    [[KBInputBufferManager shared] resetWithText:@""];
     [[KBLocalizationManager shared] reloadFromSharedStorageIfNeeded];
-    [[KBInputBufferManager shared] seedIfEmptyWithContextBefore:self.textDocumentProxy.documentContextBeforeInput
+    // 注意：微信/QQ 等宿主的 documentContext 可能是“截断窗口”，这里只更新 liveText，不要把它当作全文 manualSnapshot。
+    [[KBInputBufferManager shared] updateFromExternalContextBefore:self.textDocumentProxy.documentContextBeforeInput
                                                              after:self.textDocumentProxy.documentContextAfterInput];
 }
 
+- (void)viewWillDisappear:(BOOL)animated {
+    [super viewWillDisappear:animated];
+    [[KBBackspaceUndoManager shared] registerNonClearAction];
+}
+
 - (void)textDidChange:(id<UITextInput>)textInput {
     [super textDidChange:textInput];
     [[KBInputBufferManager shared] updateFromExternalContextBefore:self.textDocumentProxy.documentContextBeforeInput

CustomKeyboard/Utils/KBBackspaceLongPressHandler.m

@@ -11,11 +11,11 @@
 
 static const NSTimeInterval kKBBackspaceLongPressMinDuration = 0.35;
 static const NSTimeInterval kKBBackspaceRepeatInterval = 0.06;
-static const NSTimeInterval kKBBackspaceChunkStartDelay = 1.0;
+static const NSTimeInterval kKBBackspaceChunkStartDelay = 0.6;
 static const NSTimeInterval kKBBackspaceChunkRepeatInterval = 0.1;
-static const NSTimeInterval kKBBackspaceChunkFastDelay = 1.4;
+static const NSTimeInterval kKBBackspaceChunkFastDelay = 1.2;
-static const NSInteger kKBBackspaceChunkSize = 6;
+static const NSInteger kKBBackspaceChunkSize = 8;
-static const NSInteger kKBBackspaceChunkSizeFast = 12;
+static const NSInteger kKBBackspaceChunkSizeFast = 16;
 static const CGFloat kKBBackspaceClearLabelCornerRadius = 8.0;
 static const CGFloat kKBBackspaceClearLabelHeight = 26.0;
 static const CGFloat kKBBackspaceClearLabelPaddingX = 10.0;
@@ -210,34 +210,77 @@ typedef NS_ENUM(NSInteger, KBClearPhase) {
         whitespaceSet = [NSCharacterSet whitespaceAndNewlineCharacterSet];
         asciiWordSet = [NSCharacterSet characterSetWithCharactersInString:
                         @"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_"];
-        punctuationSet = [NSCharacterSet punctuationCharacterSet];
+        NSMutableCharacterSet *punct = [[NSCharacterSet punctuationCharacterSet] mutableCopy];
+        // 补齐常见中文/全角标点（避免 chunk 总是只删 1 个符号）
+        [punct addCharactersInString:@"，。！？；：、（）【】《》“”‘’·…—"];
+        punctuationSet = [punct copy];
     });
 
     __block NSInteger deleteCount = 0;
-    __block KBBackspaceChunkClass chunkClass = KBBackspaceChunkClassUnknown;
+    typedef NS_ENUM(NSInteger, KBBackspaceChunkPhase) {
+        KBBackspaceChunkPhaseWhitespace = 0,
+        KBBackspaceChunkPhasePunctuation,
+        KBBackspaceChunkPhaseCore
+    };
+    __block KBBackspaceChunkPhase phase = KBBackspaceChunkPhaseWhitespace;
+    __block KBBackspaceChunkClass coreClass = KBBackspaceChunkClassUnknown;
+
     [context enumerateSubstringsInRange:NSMakeRange(0, context.length)
                                 options:NSStringEnumerationByComposedCharacterSequences | NSStringEnumerationReverse
                              usingBlock:^(NSString *substring, __unused NSRange substringRange, __unused NSRange enclosingRange, BOOL *stop) {
         if (substring.length == 0) { return; }
-        KBBackspaceChunkClass currentClass = KBBackspaceChunkClassOther;
+        if (deleteCount >= maxCount) {
-        if ([substring rangeOfCharacterFromSet:whitespaceSet].location != NSNotFound) {
-            currentClass = KBBackspaceChunkClassWhitespace;
-        } else if ([substring rangeOfCharacterFromSet:asciiWordSet].location != NSNotFound) {
-            currentClass = KBBackspaceChunkClassASCIIWord;
-        } else if ([substring rangeOfCharacterFromSet:punctuationSet].location != NSNotFound) {
-            currentClass = KBBackspaceChunkClassPunctuation;
-        }
-
-        if (chunkClass == KBBackspaceChunkClassUnknown) {
-            chunkClass = currentClass;
-        } else if (chunkClass != currentClass) {
             *stop = YES;
             return;
         }
 
+        KBBackspaceChunkClass currentClass = KBBackspaceChunkClassOther;
+        if ([substring rangeOfCharacterFromSet:whitespaceSet].location != NSNotFound) {
+            currentClass = KBBackspaceChunkClassWhitespace;
+        } else if ([substring rangeOfCharacterFromSet:punctuationSet].location != NSNotFound) {
+            currentClass = KBBackspaceChunkClassPunctuation;
+        } else if ([substring rangeOfCharacterFromSet:asciiWordSet].location != NSNotFound) {
+            currentClass = KBBackspaceChunkClassASCIIWord;
+        }
+
+        BOOL consumed = NO;
+        while (!consumed) {
+            if (phase == KBBackspaceChunkPhaseWhitespace) {
+                if (currentClass == KBBackspaceChunkClassWhitespace) {
                     deleteCount += 1;
+                    consumed = YES;
+                } else {
+                    phase = KBBackspaceChunkPhasePunctuation;
+                }
+                continue;
+            }
+
+            if (phase == KBBackspaceChunkPhasePunctuation) {
+                if (currentClass == KBBackspaceChunkClassPunctuation) {
+                    deleteCount += 1;
+                    consumed = YES;
+                } else {
+                    phase = KBBackspaceChunkPhaseCore;
+                }
+                continue;
+            }
+
+            // phase == Core：连续删同一类（ASCII 单词 / 其它），让效果更像微信“几个字一组”
+            if (coreClass == KBBackspaceChunkClassUnknown) {
+                coreClass = currentClass;
+            }
+            if (currentClass != coreClass) {
+                *stop = YES;
+                consumed = YES;
+                continue;
+            }
+            deleteCount += 1;
+            consumed = YES;
+        }
+
         if (deleteCount >= maxCount) {
             *stop = YES;
+            return;
         }
     }];
 
@@ -480,12 +523,23 @@ typedef NS_ENUM(NSInteger, KBClearPhase) {
     if (!ivc) { return; }
     id<UITextDocumentProxy> proxy = ivc.textDocumentProxy;
     NSInteger nextEmptyRounds = emptyRounds;
-    static NSCharacterSet *sentenceBoundarySet = nil;
+    static NSCharacterSet *stopBoundarySet = nil;
-    static NSCharacterSet *whitespaceSet = nil;
+    static NSCharacterSet *trailingBoundarySet = nil;
+    static NSCharacterSet *trailingWhitespaceSet = nil;
     static dispatch_once_t onceToken;
     dispatch_once(&onceToken, ^{
-        sentenceBoundarySet = [NSCharacterSet characterSetWithCharactersInString:@".!?。！？"];
+        // stopBoundary: 遇到这些符号就停（不删除它）
-        whitespaceSet = [NSCharacterSet whitespaceAndNewlineCharacterSet];
+        // - 句末符号：. ! ? 。！？
+        // - 省略号：…（中文里“……”常用作句/段落的停顿）
+        // - 换行：\n \r（段落边界，避免一次“清空”跨段把全文删完）
+        stopBoundarySet = [NSCharacterSet characterSetWithCharactersInString:@".!?。！？…\n\r\u2028\u2029"];
+
+        // trailingBoundary: 允许作为“尾部句末符号”先删掉，再继续删上一句（更接近微信体验）
+        // 注意：不要把换行/省略号放进来，否则可能跨段/跨停顿继续删。
+        trailingBoundarySet = [NSCharacterSet characterSetWithCharactersInString:@".!?。！？"];
+
+        // trailingWhitespace: 只跳过空格/Tab（不包含换行，换行由 stopBoundarySet 处理）
+        trailingWhitespaceSet = [NSCharacterSet whitespaceCharacterSet];
     });
     KBClearPhase phase = self.backspaceClearPhase;
 
@@ -496,10 +550,9 @@ typedef NS_ENUM(NSInteger, KBClearPhase) {
         NSString *before = proxy.documentContextBeforeInput ?: @"";
         if (before.length == 0) {
             nextEmptyRounds += 1;
-            // 即使 context 为空，也尝试删一次（某些宿主延迟更新）
+            // 宿主（微信/QQ 等）可能在长文本场景下返回空 context，即使还有很多内容。
-            [[KBBackspaceUndoManager shared] captureAndDeleteBackwardFromProxy:proxy count:1];
+            // 为了避免一次“清空”误删全文：一旦拿不到 before，就立刻停止本次清空。
-            [[KBInputBufferManager shared] applyClearDeleteCount:1];
+            shouldStop = YES;
-            deletedThisTick += 1;
             break;
         }
         nextEmptyRounds = 0;
@@ -520,8 +573,9 @@ typedef NS_ENUM(NSInteger, KBClearPhase) {
         }];
         if (lastChar.length == 0) { break; }
 
-        BOOL isWhitespace = ([lastChar rangeOfCharacterFromSet:whitespaceSet].location != NSNotFound);
+        BOOL isWhitespace = ([lastChar rangeOfCharacterFromSet:trailingWhitespaceSet].location != NSNotFound);
-        BOOL isBoundary = ([lastChar rangeOfCharacterFromSet:sentenceBoundarySet].location != NSNotFound);
+        BOOL isStopBoundary = ([lastChar rangeOfCharacterFromSet:stopBoundarySet].location != NSNotFound);
+        BOOL isTrailingBoundary = ([lastChar rangeOfCharacterFromSet:trailingBoundarySet].location != NSNotFound);
 
         if (phase == KBClearPhaseSkipWhitespace) {
             if (isWhitespace) {
@@ -534,7 +588,7 @@ typedef NS_ENUM(NSInteger, KBClearPhase) {
         }
 
         if (phase == KBClearPhaseSkipTrailingBoundary) {
-            if (isBoundary) {
+            if (isTrailingBoundary) {
                 [[KBBackspaceUndoManager shared] captureAndDeleteBackwardFromProxy:proxy count:1];
                 [[KBInputBufferManager shared] applyClearDeleteCount:1];
                 deletedThisTick += 1;
@@ -544,7 +598,7 @@ typedef NS_ENUM(NSInteger, KBClearPhase) {
         }
 
         // phase == DeleteUntilBoundary
-        if (isBoundary) {
+        if (isStopBoundary) {
             shouldStop = YES; // 保留该句末符号
             break;
         }