替换UITextView中的文本

Question

我正在尝试编写一个小概念应用程序,当用户在UITextView中键入时读取字符流,当输入某个单词时,它会被替换(有点像自动更正).

我调查使用 -

(BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text;

但到目前为止我没有运气.任何人都可以给我一个提示.

非常感激!

大卫

Answer 1

这是正确的方法.它的对象是否设置为UITextView的委托？

更新: -
固定在上面说"UITextView"(我之前有"UITextField") -
添加了以下代码示例:

此方法实现位于UITextView的委托对象中(例如,其视图控制器或应用程序委托):

// replace "hi" with "hello"
- (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text {

    // create final version of textView after the current text has been inserted
    NSMutableString *updatedText = [[NSMutableString alloc] initWithString:textView.text];
    [updatedText insertString:text atIndex:range.location];

    NSRange replaceRange = range, endRange = range;

    if (text.length > 1) {
        // handle paste
        replaceRange.length = text.length;
    } else {
        // handle normal typing
        replaceRange.length = 2;  // length of "hi" is two characters
        replaceRange.location -= 1; // look back one characters (length of "hi" minus one)
    }

    // replace "hi" with "hello" for the inserted range
    int replaceCount = [updatedText replaceOccurrencesOfString:@"hi" withString:@"hello" options:NSCaseInsensitiveSearch range:replaceRange];

    if (replaceCount > 0) {
        // update the textView's text
        textView.text = updatedText;

        // leave cursor at end of inserted text
        endRange.location += text.length + replaceCount * 3; // length diff of "hello" and "hi" is 3 characters
        textView.selectedRange = endRange; 

        [updatedText release];

        // let the textView know that it should ingore the inserted text
        return NO;
    }

    [updatedText release];

    // let the textView know that it should handle the inserted text
    return YES;
}