textview 占位字

 textview 和 textfield 不同,系统并没有自带占位字符,一种方法当然可以重写系统方法,但是可以采用一个假的方法来实现这个效果.还有计数功能哟!

1.首先创建 textview 注意: 要签订代理,设定代理人.记得把控件加在视图上.

- (UITextView *)remarkTextView {

    if (_remarkTextView == nil) {

        _remarkTextView = [[UITextView alloc] initWithFrame:CGRectMake(15, 15, SCREEN_WIDTH - 30, 100)];

        _remarkTextView.text = @" 请输入您的需求...";

        _remarkTextView.textColor = [UIColor grayColor];

        _remarkTextView.font = [UIFont systemFontOfSize:15];

        _remarkTextView.layer.borderWidth = 0.5f;

        _remarkTextView.layer.cornerRadius = 4.0f;

        _remarkTextView.delegate = self;

    }

    return _remarkTextView;

}

- (UILabel *)numLabel {

    if (_numLabel == nil) {

        _numLabel = [[UILabel alloc] initWithFrame:CGRectMake(0, 120 , SCREEN_WIDTH - 10, 20)];

        _numLabel.textAlignment = NSTextAlignmentRight;

        _numLabel.text = @"0/200";

        _numLabel.textColor = [UIColor grayColor];

        _numLabel.font = [UIFont systemFontOfSize:14];

    }

    return _numLabel;

}

#pragma mark textview 代理

- (void)textViewDidChange:(UITextView *)textView {

    if (self.remarkTextView.text.length > 200) {

        NSString *subString = [self.remarkTextView.text substringToIndex:200];

        self.remarkTextView.text = subString;

        NSLog(@"限制输入200字");

    }

    self.remarkTextView.textColor = [UIColor blackColor];

    self.numLabel.text = [NSString stringWithFormat:@"%ld/200",(unsigned long)textView.text.length];

}

- (void)textViewDidBeginEditing:(UITextView *)textView {

    if ([textView.text isEqualToString:@" 请输入您的需求..."]) {

        textView.text = @"";

    }

}

- (void)textViewDidEndEditing:(UITextView *)textView {

    if (textView.text.length < 1) {

        textView.text = @" 请输入您的需求...";

        textView.textColor = [UIColor grayColor];

    }

}