Question

我有底部文本字段，当我按下那里时，我看到键盘，看看我的滚动视图如何将其所有内容滚动到键盘高度。但是，如果我按“返回”，然后再次点击最后一个文本字段，我的键盘就出现在屏幕上，但滚动视图这次没有滚动，底部文本字段留在键盘下面。

这是我的代码：

    func registerForKeyboardNotifications() {
        NotificationCenter.default.addObserver(self, selector: #selector(keyboardWasShown(_:)), name: NSNotification.Name.UIKeyboardDidShow, object: nil)            
        NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillBeHidden(_:)), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
    }

    @objc
    func keyboardWasShown(_ notification: NSNotification) {
        guard let info = notification.userInfo,
        let keyboardFrameValue = info[UIKeyboardFrameBeginUserInfoKey] as? NSValue else { return }

        let keyboardFrame = keyboardFrameValue.cgRectValue
        let keyboardSize = keyboardFrame.size
        print("keyboardSize: \(keyboardSize)")
        let contentInset = UIEdgeInsetsMake(0.0, 0.0, keyboardSize.height, 0.0)
        print("keyboardSize.height: \(keyboardSize.height)")
        scrollView.contentInset = contentInset
        scrollView.scrollIndicatorInsets = contentInset
    }

    @objc
    func keyboardWillBeHidden(_ notification: NSNotification) {
        let contentInsets = UIEdgeInsets.zero
        scrollView.contentInset = contentInsets
        scrollView.scrollIndicatorInsets = contentInsets
    }
}

extension ViewController: UITextFieldDelegate {

    func textFieldShouldReturn(_ textField: UITextField) -> Bool {
        self.view.endEditing(true)
        return true
    }
}

这是输出：

有人可以解释为什么会这样吗？

谢谢。

Answer 1

你可以尝试自动布局方法，将IBOutlet scrollBotcon说@objc func keyboardWasShown(_ notification: NSNotification) { guard let info = notification.userInfo, let keyboardFrameValue = info[UIKeyboardFrameEndUserInfoKey] as? NSValue else { return } let keyboardFrame = keyboardFrameValue.cgRectValue let keyboardSize = keyboardFrame.size self.scrollBotcon.constant = - keyboardSize.height UIView.animate(withDuration: 0.5, animations: { self.view.layoutIfNeeded() } } @objc func keyboardWillBeHidden(_ notification: NSNotification) { self.scrollBotcon.constant = 0 UIView.animate(withDuration: 0.5, animations: { self.view.layoutIfNeeded() } }

挂钩滚动查看

<html>
<head>
<title>Today's Events at the TRU Union</title>
    <style>
        p {text-align: center;}
        table {display: block; margin: auto;}
        body img{display: block;margin-left:auto;margin-right:auto;}
        h2 {text-align: center; color: red;}
    </style>

</head>
<body background="Back01.jpg" text="black">
    <div id="table"></div>
</body>
<script>
        function determine_picture_day_and_month(){
            var table_content = insert_table();
            table_content += insert_title_rules_and_image();
            return table_content;
        }

        function insert_table(){
            var daily_images = ["Weekend.gif", "Monday.gif", "Tuesday.gif", "Wednesday.gif",
                            "Thursday.gif", "Friday.gif", "Weekend.gif"];
            var days = ["Sunday", "Monday", "Tuesday", "Wednesday",
            "Thursday", "Friday", "Saturday"];
            var months = ["January", "February", "March", "April", "May", "June",
            "July", "August", "September", "October", "November", "December"];
            var dateObject = new Date();

            var current_image = daily_images[dateObject.getDay()];
            var currentday = days[dateObject.getDay()];
            var currentmonth = months[dateObject.getMonth()];

            var table_content = "<table border='1' cellpadding='5'>"
            table_content += "<tr><td width='100'>" + currentday + 
            "</td><td><img src='" + current_image + "' /></td></tr></table>";
            table_content += "<p>Today is " + currentday + ", " + currentmonth +
                " " + dateObject.getDate() + "</p>";
            return table_content;
        }

        function insert_title_rules_and_image(){
            var table_content = "<h2>TRU Student Union Daily Schedule</h2>";
            table_content += "<hr /><img src='Events.gif' /><hr />";
            return table_content;
        }
        document.getElementById("table").innerHTML = determine_picture_day_and_month();
    </script>
</html>

按返回键盘高度会改变

1 个答案: