Xamarin社区工具包选项卡点击条目时查看切换选项卡

Question

我对TabView有一个奇怪的行为。视图：

<?xml version="1.0" encoding="UTF-8"?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms" 
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
x:Class="PLUTester.Test.View.Home"
xmlns:view="clr-namespace:PLUTester.Test.View"
xmlns:controls2="clr-namespace:MarcTron.Plugin.Controls;assembly=Plugin.MtAdmob"
xmlns:local="clr-namespace:PLUTester;assembly=PLUTester"
xmlns:xtc="http://xamarin.com/schemas/2020/toolkit"
xmlns:localfonts="clr-namespace:PLUTester.AppFonts"
BackgroundColor="White">
<ContentPage.Resources>
<Style TargetType="xtc:TabViewItem">
<Setter Property="VerticalOptions" Value="Center"/>
<Setter Property="FontSize" Value="30" />
<Setter Property="FontSizeSelected" Value="35"/>
<Setter Property="FontFamily" Value="MyIcon"/>
<Setter Property="VerticalOptions" Value="FillAndExpand" />
<Setter Property="TextColor" Value="Gray" />
<Setter Property="TextColorSelected" Value="Black" />
<Setter Property="FontAttributesSelected" Value="Bold" />
<Setter Property="BadgeTextColor" Value="Black"/>
</Style>
<Style x:Key="CustomTabStyle" TargetType="xtc:TabView">
<!--<Setter Property="IsTabTransitionEnabled" Value="True" />-->
<Setter Property="TabStripHeight" Value="50" />
<Setter Property="TabContentBackgroundColor" Value="White" />
<Setter Property="TabIndicatorPlacement" Value="Bottom"/>
<Setter Property="TabIndicatorColor" Value="Black"/>
<Setter Property="TabStripPlacement" Value="Bottom" />
</Style>
</ContentPage.Resources>
<ContentPage.Content>
<Grid>
<xtc:TabView Style="{StaticResource CustomTabStyle}" IsSwipeEnabled="False">
<xtc:TabView.TabStripBackgroundView>
<Frame BackgroundColor="White" BorderColor="Gray" CornerRadius="0" Margin="-1,0,-1,0"/>
</xtc:TabView.TabStripBackgroundView>
<xtc:TabViewItem Text="{x:Static localfonts:FontIcon.SchoolOutline}">
<Grid>
<ContentView Content="{Binding TestView}"/>
</Grid>
</xtc:TabViewItem>
<xtc:TabViewItem Text="{x:Static localfonts:FontIcon.CardsOutline}">
<Grid>
<ContentView Content="{Binding LernView}"/>
</Grid>
</xtc:TabViewItem>
<xtc:TabViewItem Text="{x:Static localfonts:FontIcon.ChartLine}">
<Grid>
<ContentView Content="{Binding StatisticsView}"/>
</Grid>
</xtc:TabViewItem>
<xtc:TabViewItem Text="{x:Static localfonts:FontIcon.Podium}">
<Grid>
<ContentView Content="{Binding HighscoreView}"/>
</Grid>
</xtc:TabViewItem>
<xtc:TabViewItem Text="{x:Static localfonts:FontIcon.Tune}">
<Grid>
<ContentView>
<view:Settings/>
</ContentView>
</Grid>
</xtc:TabViewItem>
</xtc:TabView>           
</Grid>        
</ContentPage.Content>
</ContentPage>

视图模型：

private ContentView _TestView;
public ContentView TestView
{
get { return _TestView; }
set { _TestView = value;
OnPropertyChanged(nameof(TestView));
}
}
private ContentView _LernView;
public ContentView LernView
{
get { return _LernView; }
set { _LernView = value;
OnPropertyChanged(nameof(LernView));
}
}
private ContentView _StatisticsView;
public ContentView StatisticsView
{
get { return _StatisticsView; }
set { _StatisticsView = value;
OnPropertyChanged(nameof(StatisticsView));
}
}
private ContentView _HighscoreView;
public ContentView HighscoreView
{
get { return _HighscoreView; }
set { _HighscoreView = value;
OnPropertyChanged(nameof(HighscoreView));
}
}

第二个页面(LernView(包含一些条目，当我点击条目时，选项卡视图会切换回第一个页面，因此无法输入一些数据。奇怪的是，当我改变页面的位置时；LernView"；在"；TestView"；在TabView中；LernView"；工作如预期，但"；TestView"；把我踢回第一个站点。与picker的行为相同。

以下是调试窗口的输出，当点击一个条目时：

[ViewRootImpl@b8ac428[MainActivity]] ViewPostIme pointer 0
[ViewRootImpl@b8ac428[MainActivity]] ViewPostIme pointer 1
[InputMethodManager] prepareNavigationBarInfo() DecorView@add6a19[MainActivity]
[InputMethodManager] getNavigationBarColor() -16711423
[InputMethodManager] Starting input: tba=com.modev.plutester ic=com.android.internal.widget.EditableInputConnection@4a24c5d mNaviBarColor -16711423 mIsGetNaviBarColorSuccess true , NavVisible : true , NavTrans : false
[InputMethodManager] startInputInner - Id : 0
[InputMethodManager] startInputInner - mService.startInputOrWindowGainedFocus
[InputTransport] Input channel constructed: 'ClientS', fd=231
[InputTransport] Input channel destroyed: 'ClientS', fd=226
[InputMethodManager] SSI - flag : 0 Pid : 28689 view : com.modev.plutester
[InputMethodManager] prepareNavigationBarInfo() DecorView@add6a19[MainActivity]
[InputMethodManager] getNavigationBarColor() -16711423
[InputMethodManager] prepareNavigationBarInfo() DecorView@add6a19[MainActivity]
[InputMethodManager] getNavigationBarColor() -16711423
[InputMethodManager] Starting input: tba=com.modev.plutester ic=null mNaviBarColor -16711423 mIsGetNaviBarColorSuccess true , NavVisible : true , NavTrans : false
[InputMethodManager] startInputInner - Id : 0
[InputMethodManager] startInputInner - mService.startInputOrWindowGainedFocus
[InputTransport] Input channel constructed: 'ClientS', fd=230
[InputTransport] Input channel destroyed: 'ClientS', fd=231
[IInputConnectionWrapper] getExtractedText on inactive InputConnection
[IInputConnectionWrapper] requestCursorAnchorInfo on inactive InputConnection
[InsetsSourceConsumer] setRequestedVisible: visible=true, type=13, host=com.modev.plutester/crc64abfcbdcb04412aea.MainActivity, from=android.view.InsetsSourceConsumer.show:229 android.view.InsetsController.showDirectly:1437 android.view.InsetsController.controlAnimationUnchecked:1110 android.view.InsetsController.applyAnimation:1417 android.view.InsetsController.show:962 android.view.ViewRootImpl$ViewRootHandler.handleMessage:6098 android.os.Handler.dispatchMessage:106 android.os.Looper.loop:246 android.app.ActivityThread.main:8506 java.lang.reflect.Method.invoke:-2 
[SurfaceControl] hide : mNativeObject = 480531777920 - sc.mNativeObject = 480531879648 - Surface(name=Surface(name=5fb0fa1 InputMethod)/@0x49804dd - animation-leash)/@0x1b84285
[SurfaceControl] nativeSetFlags Done : Surface(name=Surface(name=5fb0fa1 InputMethod)/@0x49804dd - animation-leash)/@0x1b84285
[SurfaceControl] hide : mNativeObject = 480531777920 - sc.mNativeObject = 480531879648 - Surface(name=Surface(name=5fb0fa1 InputMethod)/@0x49804dd - animation-leash)/@0x1b84285
[SurfaceControl] nativeSetFlags Done : Surface(name=Surface(name=5fb0fa1 InputMethod)/@0x49804dd - animation-leash)/@0x1b84285
[SurfaceControl] release : mNativeObject = 480531879648 - Surface(name=Surface(name=5fb0fa1 InputMethod)/@0x49804dd - animation-leash)/@0x1b84285 / android.view.-$$Lambda$Rl1VZmNJ0VZDLK0BAbaVGis0rrA.accept:2 android.view.InsetsSourceControl.release:170 android.view.InsetsAnimationThreadControlRunner.releaseControls:119 android.view.InsetsAnimationThreadControlRunner.access$200:40 
[SurfaceControl] nativeRelease nativeObject s[480531879648]
[SurfaceControl] nativeRelease nativeObject e[480531879648]

上述条目：

<Entry Text="{Binding MaxPLU}" Keyboard="Numeric" FontSize="Medium" VerticalOptions="EndAndExpand" WidthRequest="80" HorizontalTextAlignment="Center" HorizontalOptions="Start">
<Entry.Behaviors>
<controls:NumberValidationBehavior/>
</Entry.Behaviors>
</Entry>

数字验证行为：

public class NumberValidationBehavior : Behavior<Entry>
{
protected override void OnAttachedTo(Entry entry)
{
entry.TextChanged += OnEntryTextChanged;
base.OnAttachedTo(entry);
}
protected override void OnDetachingFrom(Entry entry)
{
entry.TextChanged -= OnEntryTextChanged;
base.OnDetachingFrom(entry);
}
private static void OnEntryTextChanged(object sender, TextChangedEventArgs args)
{
if (!string.IsNullOrWhiteSpace(args.NewTextValue))
{
bool isValid = args.NewTextValue.ToCharArray().All(x => char.IsDigit(x)); //Make sure all characters are numbers
((Entry)sender).Text = isValid ? args.NewTextValue : args.NewTextValue.Remove(args.NewTextValue.Length - 1);
}
}
}

一些澄清：选项卡视图

1. MyPage1->一切如预期
2. MyPage2->点击条目会让我回到MyPage1

现在我切换页面：选项卡视图

1. MyPage2->一切如预期
2. MyPage1->点击条目会让我回到MyPage2

我做错了什么？

更新：如果我设置了条目的HorizontalTextAlignment，就会发生这种奇怪的行为。如果未设置，则条目将按预期工作

Answer 1

另一个解决方案是禁用所有在离开选项卡时打开虚拟键盘的控件(输入/编辑器(，并在其处于活动选项卡时启用。

奇怪的是，当您专注于一个条目/编辑器并浏览选项卡时，以及当您在控件聚焦后导航回一页时，它将触发Focused事件，选项卡将调整为至少在条目或编辑器上显示光标。

private bool _isLernViewActive;
public bool IsLernViewActive
{
get { return _isLernViewActive; }
set { _isLernViewActive = value;
OnPropertyChanged(nameof(IsLernViewActive));
}
}

Xaml:

<Entry Text="{Binding MaxPLU}" Keyboard="Numeric" FontSize="Medium" VerticalOptions="EndAndExpand" WidthRequest="80" 
IsEnabled={Binding IsLernViewActive} HorizontalTextAlignment="Center" HorizontalOptions="Start">
<Entry.Behaviors>
<controls:NumberValidationBehavior/>
</Entry.Behaviors>
</Entry>