Wpf 如何在文本框中正确显示文本作为背景?
我有一个文本框和一个文本提示,显示为背景: 但是作为背景的文本的位置不正确,它不是基本文本框文本的一部分。 xaml: 我期望:Wpf 如何在文本框中正确显示文本作为背景?,wpf,xaml,wpf-controls,Wpf,Xaml,Wpf Controls,我有一个文本框和一个文本提示,显示为背景: 但是作为背景的文本的位置不正确,它不是基本文本框文本的一部分。 xaml: 我期望: 如何显示自动完成。按预期提示?谢谢您的帮助 解决这个问题的一种方法是使用文本框作为视觉,而不是文本块。此TextBox必须具有与原始TextBoxBase相同的边框厚度和大小。因此,您的AutocompleteText方法应该更改如下: private static void AutocompleteText(object sender) { TextBox
如何显示自动完成。按预期提示?谢谢您的帮助 解决这个问题的一种方法是使用
文本框
作为视觉
,而不是文本块
。此TextBox
必须具有与原始TextBoxBase
相同的边框厚度和大小。因此,您的AutocompleteText
方法应该更改如下:
private static void AutocompleteText(object sender)
{
TextBoxBase txtBase = (TextBoxBase)sender;
if (txtBase != null && txtBase.Focus())
{
// Show Autocomplete hint
var visual = new TextBox()
{
BorderThickness = txtBase.BorderThickness,
BorderBrush = Brushes.Transparent,
Width = txtBase.ActualWidth,
Height = txtBase.ActualHeight,
Text = hintText,
Foreground = Brushes.Gray
};
txtBase.Background = new VisualBrush(visual)
{
Stretch = Stretch.None,
};
}
else
{
// Hide Autocomplete hint
txtBase.Background = null;
}
}
尝试将Padding=“0”
添加到文本框中。它将文本向上和向左移动了一点。@Dave,谢谢你的回复。现在看起来很棒!
namespace WpfApplication2
{
public static class Autocomplete
{
#region Hint
public static string GetHint(DependencyObject obj)
{
return (string)obj.GetValue(HintProperty);
}
public static void SetHint(DependencyObject obj, string value)
{
obj.SetValue(HintProperty, value);
}
public static readonly DependencyProperty HintProperty =
DependencyProperty.RegisterAttached("Hint", typeof(string), typeof(Autocomplete), new PropertyMetadata(string.Empty, OnTextBoxBaseFocus));
private static string hintText = string.Empty;
private static void OnTextBoxBaseFocus(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
TextBoxBase txtBase = (TextBoxBase)d;
hintText = GetHint(d);
if (txtBase == null)
return;
if ((string)e.NewValue != null && !GetHint(d).Contains(" "))
{
txtBase.GotFocus += txtBase_GotFocus;
txtBase.LostFocus += txtBase_LostFocus;
}
else
txtBase.TextChanged -= OnChanged;
}
static void txtBase_GotFocus(object sender, RoutedEventArgs e)
{
AutocompleteText(sender);
}
static void txtBase_LostFocus(object sender, RoutedEventArgs e)
{
TextBoxBase txtBase = (TextBoxBase)sender;
// Hide Autocomplete hint
txtBase.Background = null;
}
private static void OnChanged(object sender, TextChangedEventArgs e)
{
AutocompleteText(sender);
}
private static void AutocompleteText(object sender)
{
TextBoxBase txtBase = (TextBoxBase)sender;
if (txtBase != null && txtBase.Focus())
{
// Show Autocomplete hint
var visual = new TextBlock()
{
FontStyle = FontStyles.Normal,
Text = hintText,
Foreground = Brushes.Gray
};
txtBase.Background = new VisualBrush(visual)
{
Stretch = Stretch.None,
AlignmentX = AlignmentX.Left,
AlignmentY = AlignmentY.Center,
Transform = new TranslateTransform(3, 0)
};
}
else
{
// Hide Autocomplete hint
txtBase.Background = null;
}
}
#endregion
}
}
private static void AutocompleteText(object sender)
{
TextBoxBase txtBase = (TextBoxBase)sender;
if (txtBase != null && txtBase.Focus())
{
// Show Autocomplete hint
var visual = new TextBox()
{
BorderThickness = txtBase.BorderThickness,
BorderBrush = Brushes.Transparent,
Width = txtBase.ActualWidth,
Height = txtBase.ActualHeight,
Text = hintText,
Foreground = Brushes.Gray
};
txtBase.Background = new VisualBrush(visual)
{
Stretch = Stretch.None,
};
}
else
{
// Hide Autocomplete hint
txtBase.Background = null;
}
}