如何实现“无限规模”?画布效果在WPF
本文关键字：无限规模 布效果 WPF 何实现 实现 无限 | 更新日期: 2023-09-27 18:16:57
我的目标是创建一个画布，在那里你可以通过移动整个画布将子元素转换到你想要的地方(例如在rhino的grasshopper插件中)。我尝试了"translateTransform"，但问题出现了，画布的高度或宽度不够大，无法再次包括整个窗口。我试图解决这个问题，添加宽度和高度的画布，每当它被拖动，但画布的大小似乎没有改变。
这是我的window。xaml:
<Window x:Name="Window" x:Class="Oolong.Windows.Project.ProjectPlan"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:Oolong.Windows.Project"
mc:Ignorable="d"
Title="Projektplan" Height="{DynamicResource {x:Static SystemParameters.PrimaryScreenHeightKey}}" Width="{DynamicResource {x:Static SystemParameters.PrimaryScreenWidthKey}}" WindowStartupLocation="CenterOwner" ShowInTaskbar="False" Icon="/Oolong;component/Resources/Images/icon2.png">
<Window.Background>
<ImageBrush ImageSource="/Oolong;component/Resources/Images/ui/canvas_bg.png" TileMode="FlipY" Stretch="Uniform" AlignmentY="Top" Viewport="0,0,150,50" ViewportUnits="Absolute" />
</Window.Background>
<Canvas x:Name="Grid" ScrollViewer.HorizontalScrollBarVisibility="Auto" ScrollViewer.VerticalScrollBarVisibility="Auto" MouseLeftButtonDown="Grid_OnMouseLeftButtonDown" MouseDown="Grid_MouseDown" MouseMove="Grid_MouseMove" MouseUp="Grid_MouseUp" MouseWheel="Grid_OnMouseWheel" Width="{DynamicResource {x:Static SystemParameters.MaximizedPrimaryScreenWidthKey}}" Height="{DynamicResource {x:Static SystemParameters.MaximizedPrimaryScreenHeightKey}}">
<Rectangle x:Name="NewTaskRectangle" Fill="#FFF4F4F5" HorizontalAlignment="Left" Height="87" Margin="0,0,0,0" Stroke="Black" VerticalAlignment="Top" Width="208" Visibility="Hidden"/>
<Label x:Name="NewTaskLabel" Content="Gib den Namen der Aufgabe ein..." HorizontalAlignment="Left" Margin="10,17,0,0" VerticalAlignment="Top" Visibility="Hidden"/>
<TextBox x:Name="NewTaskTextBox" HorizontalAlignment="Left" Height="23" Margin="10,48,0,0" TextWrapping="Wrap" VerticalAlignment="Top" Width="189" Visibility="Hidden" KeyUp="NewTaskTextBox_OnKeyUp"/>
<Border x:Name="NewTaskTemplate" BorderBrush="Black" BorderThickness="2.5" HorizontalAlignment="Left" Height="30" Margin="0" VerticalAlignment="Top" Background="#FFE2C027" Padding="5" Focusable="True" CornerRadius="6" Width="15" Visibility="Hidden" MinWidth="150" MinHeight="30" MouseRightButtonUp="NewTaskTemplate_OnMouseRightButtonUp">
<Border.ContextMenu>
<ContextMenu x:Name="NewTaskContextMenu">
<MenuItem x:Name="AddIssueMenuItem" Header="Arbeitsschritt hinzufügen" Click="AddIssueMenuItem_OnClick"/>
<MenuItem x:Name="DeleteMenuItem" Header="Löschen" Click="DeleteMenuItem_OnClick"/>
</ContextMenu>
</Border.ContextMenu>
</Border>
<Canvas.RenderTransform>
<TransformGroup>
<ScaleTransform x:Name="ScaleTransform"/>
<TranslateTransform x:Name="Tt" />
</TransformGroup>
</Canvas.RenderTransform>
</Canvas>
</Window>
和这里相关的c#代码:
private void NewTaskTemplate_OnMouseRightButtonUp(object sender, MouseButtonEventArgs e)
{
Point position = e.GetPosition(Grid);
bool hasClickedOnTask = false;
if (App.ProjectPlan.Tasks != null)
{
var tasks = App.ProjectPlan.Tasks.DistinctBy(task => task.Position);
var selectedTasks =
tasks.Where(
(task =>
Math.Abs(task.Position.X - position.X + 10) < task.Title.Length*13 &&
Math.Abs(task.Position.Y - position.Y) < 20));
IEnumerable<Task> enumerable = selectedTasks as Task[] ?? selectedTasks.ToArray();
if (enumerable.Any())
{
_selectedTask = enumerable.Last();
hasClickedOnTask = true;
}
}
if (!hasClickedOnTask) return;
NewTaskContextMenu.IsOpen = true;
e.Handled = true;
SetGridSize();
}
Point _mStart;
Vector _mStartOffset;
private void SetGridSize()
{
Grid.Width += 250;
Grid.Height += 250;
Grid.UpdateLayout();
}
private void Grid_MouseDown(object sender, MouseButtonEventArgs e)
{
Grid.Cursor = Cursors.ScrollAll;
_mStart = e.GetPosition(Window);
_mStartOffset = new Vector(Tt.X, Tt.Y);
Grid.CaptureMouse();
}
private void Grid_MouseMove(object sender, MouseEventArgs e)
{
if (Grid.IsMouseCaptured)
{
Vector offset = Point.Subtract(e.GetPosition(Window), _mStart);
Tt.X = _mStartOffset.X + offset.X;
Tt.Y = _mStartOffset.Y + offset.Y;
SetGridSize();
}
}
private void Grid_MouseUp(object sender, MouseButtonEventArgs e)
{
Grid.ReleaseMouseCapture();
Grid.Cursor = Cursors.Arrow;
}
private void Grid_OnMouseWheel(object sender, MouseWheelEventArgs e)
{
Point position = e.GetPosition(Window);
ScaleTransform.CenterX = position.X;
ScaleTransform.CenterY = position.Y;
_gridZoom = _gridZoom + e.Delta / 2400.00;
ScaleTransform.ScaleX = _gridZoom;
ScaleTransform.ScaleY = _gridZoom;
if (e.Delta > 0)
{
SetGridSize();
}
e.Handled = true;
}
画布在开始时是一个网格，但这也不起作用。它可以在画布上移动，当然包括所有元素，但如果你把它放在窗外，你就不能再移动任何东西了，因为画布已经不在那里了。我该如何解决这个问题，让用户觉得画布是无限的?
在这种情况下，你应该用ScrollView包围你的Grid，并编辑Width和Height属性，每次在' Grid'外面拖拽元素后。像这样:
private void UIElement_OnPreviewMouseMove(object sender, MouseEventArgs e)
{
if (canmove) //field is used to define whether element dragged or not
{
var c = (Control) sender;
c.SetValue(Canvas.LeftProperty, e.GetPosition(Canvas).X - p.X);
c.SetValue(Canvas.TopProperty, e.GetPosition(Canvas).Y - p.Y);
var leftprop = Convert.ToDouble(c.GetValue(Canvas.LeftProperty));
if (leftprop > Canvas.Width)
Canvas.Width = leftprop + c.Width+10;
}
}