xamarin表格：根据键盘高度向上移动视图

Question

我正在使用xamarin表单。我在xaml中设计了一个登录表单页面。我想在出现键盘时向上移动登录表单视图，以便在平台Android和IOS的情况下都可以看到文本字段和登录按钮。如何计算键盘高度并通过动态计算键盘高度来向上移动登录表单视图。

下面是我的XAML代码：

<ContentPage> 
    <ScrollView> 
     <AbsoluteLayout HorizontalOptions="FillAndExpand" VerticalOptions="FillAndExpand"> 
      <Grid Padding="20, 30, 20, 20" RowSpacing="20" AbsoluteLayout.LayoutFlags="All" AbsoluteLayout.LayoutBounds="0,0,1,1"> 
       <Grid.RowDefinitions> 
        <RowDefinition Height="Auto" /> 
        <RowDefinition Height="Auto" /> 
        <RowDefinition Height="Auto" /> 
        <RowDefinition Height="Auto" /> 
        <RowDefinition Height="Auto" /> 
        <RowDefinition Height="Auto" /> 
       </Grid.RowDefinitions> 

       <Image Grid.Row="0" Source="login.png" HorizontalOptions="Center" VerticalOptions="Center"/> 

       <Entry Grid.Row="2" x:Name="entryUserName" HorizontalOptions="Fill" Placeholder="Username" PlaceholderColor="#707070" Text="{Binding UserName,Mode=TwoWay}" Margin="5"/> 

       <BoxView Grid.Row="2" HeightRequest="1" HorizontalOptions="Fill" BackgroundColor="#707070" VerticalOptions="End"/> 

       <Entry Grid.Row="3" x:Name="entryPassword" Text="{Binding Password,Mode=TwoWay}" Placeholder="Password" PlaceholderColor="#707070" Margin="5" HorizontalOptions="Fill" IsPassword="True"/> 

       <BoxView Grid.Row="3" HeightRequest="1" HorizontalOptions="Fill" BackgroundColor="#707070" VerticalOptions="End"/> 

       <Button Grid.Row="5" HorizontalOptions="Center" VerticalOptions="Center" Text="Login" Command="{Binding doLoginCommand}" CommandParameter="entryUserName,entryPassword" /> 

      </Grid>   
     </AbsoluteLayout> 
    </ScrollView> 
</ContentPage> 

我不想执行任何种类的页面定制渲染。是否有任何资源可以通过它编写依赖项服务来计算不同移动视图跨平台的键盘高度。 我经历了this，但它有一些我不想要的自定义渲染。

Answer 1

选项1：

安卓 添加到您的清单：

<activity //Your MainActivity 
     android:windowSoftInputMode="stateVisible|adjustResize" ... > 
     ... 
</activity> 

iOS设备上： 加入这个NuGet包： https://www.nuget.org/packages/Xam.Plugins.Forms.KeyboardOverlap/

和初始化它：

Xamarin.Forms.Init();//platform specific init 
KeyboardOverlapRenderer.Init(); 

选项2：

将此代码添加到您的网页类：

 protected override void OnAppearing() 
     { 
      base.OnAppearing(); 
      entryUserName.Focused += InputFocused; 
      entryPassword.Focused += InputFocused; 
      entryUserName.Unfocused += InputUnfocused; 
      entryPassword.Unfocused += InputUnfocused; 
     } 

     protected override void OnDisappearing() 
     { 
      base.OnDisappearing(); 
      entryUserName.Focused -= InputFocused; 
      entryPassword.Focused -= InputFocused; 
      entryUserName.Unfocused -= InputUnfocused; 
      entryPassword.Unfocused -= InputUnfocused; 
     } 
     void InputFocused(object sender, EventArgs args){ 
      Content.LayoutTo(new Rectangle(0,-360, Content.Bounds.Width, Content.Bounds.Height)); 
     } 

     void InputUnfocused(object sender, EventArgs args){ 
      Content.LayoutTo(new Rectangle(0,0, Content.Bounds.Width, Content.Bounds.Height)); 
     } 

Answer 2

这里是一个进入渲染迫使Android上SoftInputMode，希望这有助于：

using System; 
using Xamarin.Forms; 
using Xamarin.Forms.Platform.Android; 
using Android.Widget; 
using Android.Util; 
using Android.OS; 
using Android.Views.InputMethods; 
using System.Threading; 
using Android.Views; 
using Android.App; 

[assembly: ExportRenderer(typeof(FormsEntry), typeof(DroidEntryRenderer))] 
namespace XXX 
{ 
    public class DroidEntryRenderer : EntryRenderer, IEntryMessages 
    { 
     private bool _inititialized = false; 
     EditText editText; 

     protected override void OnElementChanged(ElementChangedEventArgs<Entry> e) 
     { 
      base.OnElementChanged(e); 
      if (e.OldElement != null) 
      { 
       // unhook old events 
      } 
      if (e.NewElement != null) 
      { 
       // hook new events 
       editText = (EditText)Control; 
       var entry = e.NewElement as FormsEntry; 

       (this.Element as FormsEntry).OnShowKeyboard += DroidEntryRenderer_showKeyboard; 
       (this.Element as FormsEntry).OnChangeIme += DroidEntryRenderer_changeIme; 

       if(entry.KeyboardInputMode == SoftInputMode.AdjustNothing) 
        (Forms.Context as Activity).Window.SetSoftInputMode(SoftInput.AdjustNothing); 
       else if(entry.KeyboardInputMode == SoftInputMode.AdjustResize) 
        (Forms.Context as Activity).Window.SetSoftInputMode(SoftInput.AdjustResize); 
       else 
        (Forms.Context as Activity).Window.SetSoftInputMode(SoftInput.AdjustPan); 

       if(entry.SetImeToNext){ 
        Control.ImeOptions = Android.Views.InputMethods.ImeAction.Next; 
        Control.SetImeActionLabel("Next", Android.Views.InputMethods.ImeAction.Next); 

        switch(entry.CustomImeAction){ 
         case ImeAction.Email: 
          editText.EditorAction += (object sender, TextView.EditorActionEventArgs args) => 
          { 
           MessagingCenter.Send<IEntryMessages>(this, "Email"); 
          }; 
          break; 
         case ImeAction.Password: 
          editText.EditorAction += (object sender, TextView.EditorActionEventArgs args) => 
          { 
           MessagingCenter.Send<IEntryMessages>(this, "Password"); 
          }; 
          break; 
        } 
       } 

       if (entry.HasBorder) 
       { 
        editText.SetBackgroundResource(Resource.Drawable.BorderEntry); 
       } 

       // edit properties 
       if (entry.Font != Font.Default) 
       { 
        RendererHelper.SetTextViewFont(editText, entry.Font); 
       } 
       if (entry.PlaceholderColor != Color.Default) 
        editText.SetHintTextColor(entry.PlaceholderColor.ToAndroid()); 

       switch (entry.XAlign) 
       { 
       case Xamarin.Forms.TextAlignment.Start: 
        editText.Gravity = Android.Views.GravityFlags.CenterVertical | Android.Views.GravityFlags.Left; 
        break; 

       case Xamarin.Forms.TextAlignment.Center: 
        editText.Gravity = Android.Views.GravityFlags.Center; 
        break; 

       case Xamarin.Forms.TextAlignment.End: 
        editText.Gravity = Android.Views.GravityFlags.CenterVertical | Android.Views.GravityFlags.Right; 
        editText.SetPadding(0, editText.PaddingTop, 0, editText.PaddingBottom); 
        break; 
       } 

       if (entry.ReturnKeyType == KeyboardType.Done) 
        editText.ImeOptions = global::Android.Views.InputMethods.ImeAction.Done; 
       else if (entry.ReturnKeyType == KeyboardType.Next) 
        editText.ImeOptions = global::Android.Views.InputMethods.ImeAction.Next; 

      } 
     } 

     void DroidEntryRenderer_showKeyboard() 
     { 
      ShowKeyboard(); 
     } 

     void DroidEntryRenderer_changeIme() 
     { 
      ChangeIme(); 
     } 

     public void ChangeIme(){ 
      Control.ImeOptions = Android.Views.InputMethods.ImeAction.Next; 
      Control.SetImeActionLabel("Next", Android.Views.InputMethods.ImeAction.Next); 
     } 

     public void ShowKeyboard() 
     { 
      Device.BeginInvokeOnMainThread(() => 
      { 
       this.Control.RequestFocus(); 
       InputMethodManager inputMethodManager = this.Control.Context. 
       GetSystemService(Android.Content.Context.InputMethodService) as InputMethodManager; 
       inputMethodManager.ShowSoftInput(this.Control, ShowFlags.Forced); 
       inputMethodManager.ToggleSoftInput(ShowFlags.Forced, HideSoftInputFlags.ImplicitOnly); 
      }); 
     } 

    } 
}