如何获取 Android 和 iOS 上的键盘高度（Xamarin Forms）？

Question

我想得到( )和( )Keyboard上的高度。AndroidiOSXamarin Forms

当Screen显示有Portraitmode和Landscapemode时，如何获取height值？

我找到了Swift关于的参考资料iOS：

iPhone 屏幕键盘的高度是多少？

如何获取键盘的高度？

不过可以给我源代码吗Xamarin

以及如何获得键盘的高度Android？

请帮我！

Answer 1

适用于 iOS

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有两种方法可以做到这一点！

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第一种方法：如果您的应用程序很小，则为一个 UIViewController 实现它，如下所示：

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第 1 步：添加用于显示和隐藏观察者的字段：

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private NSObject _keyboardObserverWillShow;\nprivate NSObject _keyboardObserverWillHide;\n

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步骤 2：更新 ViewDidLoad 和 ViewDidUnload 覆盖，以便在键盘显示或隐藏时添加/删除观察者：

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public override void ViewDidLoad() {\n    base.ViewDidLoad ();\n    _keyboardObserverWillShow = NSNotificationCenter.DefaultCenter.AddObserver(UIKeyboard.DidShowNotification, KeyboardDidShowNotification);\n    _keyboardObserverWillHide = NSNotificationCenter.DefaultCenter.AddObserver(UIKeyboard.WillHideNotification, KeyboardWillHideNotification);\n}\n    \npublic override void ViewDidUnload() {\n    base.ViewDidUnload();\n    NSNotificationCenter.DefaultCenter.RemoveObserver(_keyboardObserverWillShow);\n    NSNotificationCenter.DefaultCenter.RemoveObserver(_keyboardObserverWillHide);\n}\n

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第 3 步：然后填充为每个观察者执行的函数KeyboardDidShowNotification& 。KeyboardWillHideNotification它相当长，需要我花一些时间来解释每个部分，但您可以在评论中询问我。其过程如下：

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private void KeyboardWillHideNotification (NSNotification notification) \n{\n    UIView activeView = View.FindFirstResponder();\n    if (activeView == null)\n        return;\n    \n    UIScrollView scrollView = activeView.FindSuperviewOfType (this.View, typeof(UIScrollView)) as UIScrollView;\n    if (scrollView == null)\n        return;\n    \n    // Reset the content inset of the scrollView and animate using the current keyboard animation duration\n    double animationDuration = UIKeyboard.AnimationDurationFromNotification(notification);\n    UIEdgeInsets contentInsets = new UIEdgeInsets(0.0f, 0.0f, 0.0f, 0.0f);\n    UIView.Animate(animationDuration, delegate{\n        scrollView.ContentInset = contentInsets;\n        scrollView.ScrollIndicatorInsets = contentInsets;\n    });\n}   \n\nprivate void KeyboardDidShowNotification (NSNotification notification) \n{\n    UIView activeView = View.FindFirstResponder();\n    if (activeView == null)\n        return;\n\n    ((UITextField)activeView).ShowDoneButtonOnKeyboard();\n\n    UIScrollView scrollView = activeView.FindSuperviewOfType(this.View, typeof(UIScrollView)) as UIScrollView;\n    if (scrollView == null)\n        return;\n    \n    RectangleF keyboardBounds = UIKeyboard.BoundsFromNotification(notification);\n    \n    UIEdgeInsets contentInsets = new UIEdgeInsets(0.0f, 0.0f, keyboardBounds.Size.Height, 0.0f);\n    scrollView.ContentInset = contentInsets;\n    scrollView.ScrollIndicatorInsets = contentInsets;\n    \n    // If activeField is hidden by keyboard, scroll it so it\'s visible\n    RectangleF viewRectAboveKeyboard = new RectangleF(this.View.Frame.Location, new SizeF(this.View.Frame.Width, this.View.Frame.Size.Height - keyboardBounds.Size.Height));\n    \n    RectangleF activeFieldAbsoluteFrame = activeView.Superview.ConvertRectToView(activeView.Frame, this.View);\n    // activeFieldAbsoluteFrame is relative to this.View so does not include any scrollView.ContentOffset\n    \n    // Check if the activeField will be partially or entirely covered by the keyboard\n    if (!viewRectAboveKeyboard.Contains(activeFieldAbsoluteFrame)) {\n        // Scroll to the activeField Y position + activeField.Height + current scrollView.ContentOffset.Y - the keyboard Height\n        PointF scrollPoint = new PointF(0.0f, activeFieldAbsoluteFrame.Location.Y + activeFieldAbsoluteFrame.Height + scrollView.ContentOffset.Y - viewRectAboveKeyboard.Height);\n        scrollView.SetContentOffset(scrollPoint, true);\n    }\n}\n

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第二种方法：创建一个键盘处理程序，您可以通过BaseViewController将其用于每个页面

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对于安卓：

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您可以按照此处 stackOverflow Xamarin 解决方案中提到的解决方案进行操作((Activity)Forms.Context).Window.SetSoftInputMode(SoftInput.AdjustPan);。有时，\xe2\x80\x99 不起作用，因此您可以使用它来修复它。PS：没有\xe2\x80\x99复制这些答案，因为\xe2\x80\x99没有重写答案的意义。

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