I have set a Grid's background brush as an ImageBrush.
But when I set the Grid's FlowDirection to RightToLeft, the image is flipped horizontically.
Is it possible to (un)flip the grid background ImageBrush using a certain Transition or any other way?
Not much you can do about that with sensible means (there same means that are far from sensible).
Instead place an Image element as the first item in the Grid with Grid.RowSpan, Grid.ColumnSpan to cover all the cells. Use Stretch="Fill" on the Image since thats how a background typically behaves.
Well, i do understand that my comment is outdated, but this question is popping up one of the first in Google search, so here is my solution:
I was localizing the application for the right-to-left culture. The simple decision to set FlowDirection=RTL comes with unexpected drawbacks like the background containing the company logo is flipped. I have applied the matrix transformation for the image brush used to render the background:
var mbgBrush = TryFindResource("MainBackground") as Brush;
if (mbgBrush == null) return null;
if (FlowDirection == FlowDirection.LeftToRight) return mbgBrush;
var mainBgImageBrush = mbgBrush as ImageBrush;
if (mainBgImageBrush == null) return mbgBrush;
var flipXaxis = new MatrixTransform(-1.0, 0, 0, 1.0, 1, 0);
var flippedBrush = new ImageBrush
{
Stretch = Stretch.None,
Opacity = 1.0,
ImageSource = mainBgImageBrush.ImageSource,
RelativeTransform = flipXaxis
};
return flippedBrush;
Related
I'd like to know if it's possible to:
I have window (Window1) with listview. Double click on element (Element1) of this listview open little popup window (Window2).
I'd like to set Element1 and Window2 opacity to 1, but Window1 to 0.2
Window2 is open as topmost with ShowDialog().HasValue, like
this.Opacity = 0.2;
selected.opacity = 1;
Window2.opacity = 1;
if(Window2.ShowDialog().HasValue())
this.Opacity = 1;
#EDIT:
main window, called "Window1":
private void Border_PreviewMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
if (e.ClickCount == 2)
{
if (popup != null)
popup.Close();
popup = new PopupWindow(ListView.SelectedItem as SelectedItem, sender as Border, this);
popup.Topmost = true;
((Border)sender).Opacity = 1;
this.Opacity = 0.2;
popup.Opacity = 1;
if (popup.ShowDialog().HasValue)
{
this.Opacity = 1;
}
}
}
Unfortunately, what you are trying to achieve cannot be directly accomplished with WPF because Opacity values are kind of inherited by child controls. From the UIElement.Opacity Property page on MSDN:
Opacity is applied from parent elements on down the element tree to child elements, but the visible effects of the nested opacity settings aren't indicated in the property value of individual child elements. For instance, if a list has a 50% (0.5) opacity and one of its list items has its own opacity set to 20% (0.2), the net visible opacity for that list item will be rendered as if it were 10% (0.1), but the property value of the list item Opacity property would still be 0.2 when queried.
However, it is possible to fake your desired look by making certain elements within the Window semi opaque, while still having Opacity="1.0" for child elements. So, try removing the Opacity setting from the Window and instead set the Background to a see through colour like this:
window.Background = new SolidColorBrush(Color.FromArgb(0, 0, 0, 0));
Or even simpler:
window.Background = Brushes.Transparent;
Using a combination of transparent colours and low Opacity values on certain UI elements should get you what you want eventually.
I have a canvas with a background image:
var bi = new BitmapImage(new Uri(imgLocFull));
var ib = new ImageBrush(bi) {Stretch = Stretch.UniformToFill};
MyCanvas.Background = ib;
I am overlaying various shapes on the image, and want the position of the shapes relative to the background image to be fixed.
If my application window is resized, the amount of the image that is cropped, horizontally and vertically, changes, and when my shapes are redrawn, they do not appear in the same position on the background image.
How can I determine how much of the image has been cropped (to apply an adjustment factor to the overlaid objects' positions?) Or is there a better way of fixing the location of a shape relative to the background image?
Here is my present drawing code:
var l = new Ellipse();
var scb = new SolidColorBrush();
scb.Color = Color.FromRgb(rCol, gCol, bCol);
l.Fill = scb;
l.StrokeThickness = 0;
l.Width = 3;
l.Height = 3;
Canvas.SetBottom(l, point.Y); // * clipping factor here?
Canvas.SetLeft(l, point.X); // * clipping factor here?
MyCanvas.Children.Add(l);
EDIT: Further Clarification
Here's a concrete example of what I am trying to achieve. My image is an aerial photograph, and I want to mark a particular geographical feature (with, say, an ellipse.)
When the window is resized, the ellipse doesn't stay on the feature, it stays relative to the left and top of the canvas.
I can get it closer to the right place by moving it using a factor (newx = newheight/oldheight * oldx) but this doesn't quite work because of the UniformToFill stretch mode, which sees some of the image clipped off the canvas.
The Top and Left of the Canvas are 'anchored', while the Bottom and Right move when resizing... try setting the Canvas.Top Attached Property instead, along with the Canvas.Left Attached Property as you are:
var l = new Ellipse();
var scb = new SolidColorBrush();
scb.Color = Color.FromRgb(rCol, gCol, bCol);
l.Fill = scb;
l.StrokeThickness = 0;
l.Width = 3;
l.Height = 3;
Canvas.SetTop(l, point.Y); // * clipping factor here?
Canvas.SetLeft(l, point.X); // * clipping factor here?
MyCanvas.Children.Add(l);
UPDATE >>>
You asked Or is there a better way of fixing the location of a shape relative to the background image?
I answered this question, so I don't understand why you would need to do anything else... your objects will not move when the screen in resized *if you only set the Grid.Top and Grid.Left properties.
Im working on flowchart kind of application in asp.net using silverlight.. Im a beginner in Silvelight, Creating the elements (Rectangle,Ellipse,Line.. ) dynamically using SHAPE and LINE Objects in codebehind (c#)
These shapes will be generated dynamically, meaning I'll be calling a Web service on the backend to determine how many objects/shapes need to be created. Once this is determined, I'll need to have the objects/shapes connected together.
how to connect dynamically created shapes with a line in Silverlight like a flowchart.
I read the below article, but its not working for me, actualHeight & actualWidth of shapes values are 0.
Connecting two shapes together, Silverlight 2
here is my MainPage.xaml
<UserControl x:Class="LightTest1.MainPage">
<Canvas x:Name="LayoutRoot" Background="White">
<Canvas x:Name="MyCanvas" Background="Red"></Canvas>
<Button x:Name="btnPush" Content="AddRectangle" Height="20" Width="80" Margin="12,268,348,12" Click="btnPush_Click"></Button>
</Canvas>
code behind MainPage.xaml.cs
StackPanel sp1 = new StackPanel();
public MainPage()
{
InitializeComponent();
sp1.Orientation = Orientation.Vertical;
MyCanvas.Children.Add(sp1);
}
Rectangle rect1;
Rectangle rect2;
Line line1;
private void btnPush_Click(object sender, RoutedEventArgs e)
{
rect1 = new Rectangle()
{
Height = 30,
Width = 30,
StrokeThickness = 3,
Stroke = new SolidColorBrush(Colors.Red),
};
sp1.Children.Add(rect1);
rect2 = new Rectangle()
{
Height = 30,
Width = 30,
StrokeThickness = 3,
Stroke = new SolidColorBrush(Colors.Red),
};
sp1.Children.Add(rect2);
connectShapes(rect1, rect2);
}
private void connectShapes(Shape s1, Shape s2)
{
var transform1 = s1.TransformToVisual(s1.Parent as UIElement);
var transform2 = s2.TransformToVisual(s2.Parent as UIElement);
var lineGeometry = new LineGeometry()
{
StartPoint = transform1.Transform(new Point(1, s1.ActualHeight / 2.0)),
EndPoint = transform2.Transform(new Point(s2.ActualWidth, s2.ActualHeight / 2.0))
};
var path = new Path()
{
Data = lineGeometry,
Stroke = new SolidColorBrush(Colors.Green),
};
sp1.Children.Add(path);
}
what I am doing in button click event is just adding two rectangle shapes and tring to connect them with a line (like flowchart).
Please suggest what is wrong in my code..
Try replacing the line
connectShapes(rect1, rect2);
with
Dispatcher.BeginInvoke(() => connectShapes(rect1, rect2));
I'm not sure of the exact reason why this works, but I believe the shapes are only rendered once control passes out of your code, and only once they are rendered do the ActualWidth and ActualHeight properties have a useful value. Calling Dispatcher.BeginInvoke calls your code a short time later; in fact, you may notice the lines being drawn slightly after the rectangles.
The TransformToVisual method behaves in much the same way as the ActualWidth and ActualHeight properties. It will return an identity transformation if the shape hasn't been rendered. Even if your lines were being drawn with a definite width and height, they would end up being drawn all on top of one another at the top-left.
I also found that I needed to add the lines to the Canvas, not the StackPanel, in order for them to be drawn over the rectangles. Otherwise the StackPanel quickly filled up with lines with a lot of space above them.
I need help in unifying size of elements in stackpanel
void MainPageLoaded(object sender, RoutedEventArgs e)
{
var random = new Random();
for (var i = 0; i < 5; i++)
{
var grid = new Grid();
var border = new Border()
{
Height = random.Next(50, 150),
Width = random.Next(50, 150),
Margin = new Thickness(10),
BorderBrush = new SolidColorBrush(Colors.White),
BorderThickness = new Thickness(1)
};
grid.Children.Add(border);
imageBoxesStackPanel.Children.Add(grid);
}
var h = imageBoxesStackPanel.Children.Max(n => n.DesiredSize.Height);
what I am trying to achieve is to find max height and max width of each grid in stackpanel and apply it to all of them. The problem is that desired size is always wrong.
You can only do this in a custom way after a measure/arrange pass, before that the sizes won't be visible.
After that (in the OnLoaded event, which you have), you can use the ActualHeight and ActualWidth of the grids.
In short:
var h = imageBoxesStackPanel.Children.Max(n => n.ActualHeight);
This is however bad for performance and will trigger another layout pass.
Remarks:
In WPF the best solution would be a SharedSizeGroup or a UniformGrid. This is not implemented in Silverlight, but there are people who have implemented it.
In WPF there is the UniformGrid to do this job, but unfortunately it's not implemented for Silverlight by default. There are several alternatives for it, e.g. this one
I a grid on my silverlight control, I am programatically adding a canvas, and in the canvas I am loading and displaying Image.
I'm also adding a rotation to the canvas. The problem is that by default the CenterX and CenterY of the rotation is the top left of the canvas. What I want is the rotation to happen around the centre of the canvas.
To do this, I've tried setting the CenterX and CenterY of the Rotation to the Images ActualWidth / 2 and ActualHeight / 2, however I've discovered that ActualWidth and ActualHeight are not always populated, at least not right away. How can I force them to get updated?
Even using the DownloadProgress event on the image doesn't seem to guarantee the ActualWidth and ActualHeight are populated, and neither does using this.Dispatcher.BeginInvoke()...
Image imgTest = new Image();
Canvas cnvTest = new Canvas();
Uri uriImage = new Uri("myurl", UriKind.RelativeOrAbsolute);
System.Windows.Media.Imaging.BitmapImage bmpDisplay = new System.Windows.Media.Imaging.BitmapImage(uriImage);
bmpDisplay.DownloadProgress += new EventHandler<System.Windows.Media.Imaging.DownloadProgressEventArgs>(this.GetActualDimensionsAfterDownload);
imgTest.Source = bmpDisplay;
imgTest.Stretch = Stretch.Uniform;
imgTest.HorizontalAlignment = HorizontalAlignment.Center;
imgTest.VerticalAlignment = VerticalAlignment.Center;
cnvTest.Children.Add(imgTest);
this.grdLayout.Children.Add(imgTest);
this.Dispatcher.BeginInvoke(new Action(GetActualDimensions));
To update the ActualWidth and ActualHeight of a FrameworkElement you will have to call UpdateLayout.
Unfortunately, calling updateLayout doesn't always work either depending on your situation.
I've had better luck doing something like:
whateverUIElement.Dispatcher.BeginInvoke(()
{
//code that needs width/height here
}
);
but even that fails too often.
Most reliable method I found is to use DependencyPropertyDescriptor AddValueChanged listeners of ActualWidth and ActualHeight instead of OnLayoutUpdated to get element sizes after rendering
DependencyPropertyDescriptor descriptor = DependencyPropertyDescriptor.FromProperty(ActualWidthProperty, typeof(StackPanel));
if (descriptor != null)
{
descriptor.AddValueChanged(uiPanelRoot, DrawPipelines_LayoutUpdated);
}
descriptor = DependencyPropertyDescriptor.FromProperty(ActualHeightProperty, typeof(StackPanel));
if (descriptor != null)
{
descriptor.AddValueChanged(uiPanelRoot, DrawPipelines_LayoutUpdated);
}
void DrawPipelines_LayoutUpdated(object sender, EventArgs e)
{
// Point point1 = elementInstrumentSampleVial.TranslatePoint(
// new Point(11.0, 15.0), uiGridMainInner);
}
Instead of using StackPanel, Grid etc. use base element that you are depending on for relative sizes