修改UI

CustomKeyboard/View/KBStreamTextView.m

@@ -346,10 +346,28 @@ static inline NSString *KBTrimRight(NSString *s) {
     if (ivc) {
         id<UITextDocumentProxy> proxy = ivc.textDocumentProxy;
         if ([proxy conformsToProtocol:@protocol(UITextDocumentProxy)]) {
-            NSString *context = proxy.documentContextBeforeInput ?: @"";
-            for (NSUInteger i = 0; i < context.length; i++) {
-                [proxy deleteBackward];
+            // 若用户把光标放在中间，需要同时删掉光标前后的内容再插入分片
+            BOOL canAdjustCaret = [proxy respondsToSelector:@selector(adjustTextPositionByCharacterOffset:)];
+            if (canAdjustCaret) {
+                NSString *contextAfter = proxy.documentContextAfterInput ?: @"";
+                while (contextAfter.length > 0) {
+                    NSInteger offset = (NSInteger)contextAfter.length;
+                    [proxy adjustTextPositionByCharacterOffset:offset];
+                    for (NSUInteger i = 0; i < contextAfter.length; i++) {
+                        [proxy deleteBackward];
+                    }
+                    contextAfter = proxy.documentContextAfterInput ?: @"";
+                }
             }
+
+            NSString *contextBefore = proxy.documentContextBeforeInput ?: @"";
+            while (contextBefore.length > 0) {
+                for (NSUInteger i = 0; i < contextBefore.length; i++) {
+                    [proxy deleteBackward];
+                }
+                contextBefore = proxy.documentContextBeforeInput ?: @"";
+            }
+
             if (rawText.length > 0) {
                 [proxy insertText:rawText];
             }