添加按钮文字预览提示

CustomKeyboard/View/KBKeyboardView.m

@@ -8,6 +8,7 @@
 #import "KBKey.h"
 #import "KBResponderUtils.h" // 封装的响应链工具
 #import "KBSkinManager.h"
+#import "KBKeyPreviewView.h"
 
 @interface KBKeyboardView ()
 @property (nonatomic, strong) UIView *row1;
@@ -17,6 +18,7 @@
 @property (nonatomic, strong) NSArray<NSArray<KBKey *> *> *keysForRows;
 // 长按退格的一次次删除控制标记（不使用 NSTimer，仅用 GCD 递归调度）
 @property (nonatomic, assign) BOOL backspaceHoldActive;
+@property (nonatomic, strong) KBKeyPreviewView *previewView;
 @end
 
 @implementation KBKeyboardView
@@ -463,6 +465,53 @@
     }
 }
 
+// 在字符键按下时，显示一个上方气泡预览（类似系统键盘）。
+- (void)showPreviewForButton:(KBKeyButton *)button {
+    KBKey *key = button.key;
+    if (key.type != KBKeyTypeCharacter) return;
+
+    if (!self.previewView) {
+        self.previewView = [[KBKeyPreviewView alloc] initWithFrame:CGRectZero];
+        self.previewView.hidden = YES;
+        [self addSubview:self.previewView];
+    }
+
+    [self.previewView configureWithKey:key icon:button.iconView.image];
+
+    // 计算预览视图位置：在按钮上方稍微偏上
+    CGRect btnFrameInSelf = [button convertRect:button.bounds toView:self];
+    CGFloat previewWidth  = MAX(CGRectGetWidth(btnFrameInSelf) * 1.4, 42.0);
+    CGFloat previewHeight = CGRectGetHeight(btnFrameInSelf) * 1.2;
+    CGFloat centerX = CGRectGetMidX(btnFrameInSelf);
+    CGFloat centerY = CGRectGetMinY(btnFrameInSelf) - previewHeight * 0.6;
+
+    self.previewView.frame = CGRectMake(0, 0, previewWidth, previewHeight);
+    self.previewView.center = CGPointMake(centerX, centerY);
+    self.previewView.alpha = 0.0;
+    self.previewView.hidden = NO;
+
+    [UIView animateWithDuration:0.08
+                          delay:0
+                        options:UIViewAnimationOptionBeginFromCurrentState | UIViewAnimationOptionCurveEaseOut
+                     animations:^{
+                         self.previewView.alpha = 1.0;
+                     }
+                     completion:nil];
+}
+
+- (void)hidePreview {
+    if (!self.previewView || self.previewView.isHidden) return;
+    [UIView animateWithDuration:0.06
+                          delay:0
+                        options:UIViewAnimationOptionBeginFromCurrentState | UIViewAnimationOptionCurveEaseIn
+                     animations:^{
+                         self.previewView.alpha = 0.0;
+                     }
+                     completion:^(BOOL finished) {
+                         self.previewView.hidden = YES;
+                     }];
+}
+
 // 长按退格：按住时以小间隔逐个删除；松手停止。（不使用 NSTimer/DisplayLink）
 - (void)onBackspaceLongPress:(UILongPressGestureRecognizer *)gr {
     switch (gr.state) {