修改功能

CustomKeyboard/View/KBFunctionView.m

@@ -232,9 +232,39 @@ static NSString * const kKBFunctionTagCellId = @"KBFunctionTagCellId";
         }
     }
 }
-- (void)onTapDelete { NSLog(@"点击：删除"); }
-- (void)onTapClear { NSLog(@"点击：清空"); }
-- (void)onTapSend { NSLog(@"点击：发送"); }
+- (void)onTapDelete {
+    NSLog(@"点击：删除");
+    // 单次删除一个字符（从宿主 App 的文本框光标前）
+    UIInputViewController *ivc = [self findInputViewController];
+    id<UITextDocumentProxy> proxy = ivc.textDocumentProxy;
+    [proxy deleteBackward];
+}
+- (void)onTapClear {
+    NSLog(@"点击：清空");
+    // 连续删除，直到当前输入位置之前无文本
+    UIInputViewController *ivc = [self findInputViewController];
+    id<UITextDocumentProxy> proxy = ivc.textDocumentProxy;
+    // 为避免极端情况下的长时间阻塞，按块删除
+    NSInteger guard = 0;
+    while (proxy.hasText && guard < 10000) { // 合理的上限保护
+        NSString *before = proxy.documentContextBeforeInput ?: @"";
+        // 优先批量删除当前可见的 before 字符数
+        NSInteger count = before.length > 0 ? before.length : 1;
+        for (NSInteger i = 0; i < count; i++) {
+            [proxy deleteBackward];
+        }
+        guard += count;
+    }
+    // 同步重置功能区里的占位文案
+    self.pasteView.placeholderLabel.text = @"点击粘贴TA的话";
+}
+- (void)onTapSend {
+    NSLog(@"点击：发送");
+    // 发送：插入换行。大多数聊天类 App 会把回车视为“发送”
+    UIInputViewController *ivc = [self findInputViewController];
+    id<UITextDocumentProxy> proxy = ivc.textDocumentProxy;
+    [proxy insertText:@"\n"];
+}
 
 #pragma mark - Lazy
 
@@ -354,4 +384,18 @@ static NSString * const kKBFunctionTagCellId = @"KBFunctionTagCellId";
 - (UIButton *)clearButton { return self.clearButtonInternal; }
 - (UIButton *)sendButton { return self.sendButtonInternal; }
 
+#pragma mark - Find Owner Controller
+
+// 在视图的响应链中查找宿主 UIInputViewController（KeyboardViewController）
+- (UIInputViewController *)findInputViewController {
+    UIResponder *responder = self;
+    while (responder) {
+        if ([responder isKindOfClass:[UIInputViewController class]]) {
+            return (UIInputViewController *)responder;
+        }
+        responder = responder.nextResponder;
+    }
+    return nil;
+}
+
 @end