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Гта вайстити

Draw shapes

  • 12 minutes to read
  • Contributors

Learn how to draw shapes, such as ellipses, rectangles, polygons, and paths.

The Path class is the way to visualize a fairly complex vector-based drawing language in a XAML UI; for example, you can draw Bezier curves.

Important APIs: Гта вайстити class, Windows.UI.Xaml.Shapes namespace, Windows.UI.Xaml.Media namespace

Two sets of classes define a region of space in XAML UI: Shape classes and Geometry classes.

The main difference between these classes is that a Shape has a brush associated with it and can be гта вайстити to the screen, and a Geometry simply defines a region of space and is not rendered unless it helps contribute information to another UI property. You can think of a Shape гта вайстити a UIElement with its boundary defined by a Geometry. This topic covers mainly the Shape classes.

The Shape classes are Line, Ellipse, Rectangle, Polygon, Polyline, and Path.

Path is interesting because it can define an arbitrary geometry, and the Geometry class is involved here because that's one way to define the parts of a Path.

Fill and Stroke for shapes

For a Shape to render to the app canvas, you must associate a Brush with it.

Set гта вайстити Fill property of the Shape to the Brush you want. For more info about brushes, see Using brushes.

A Shape can also have a Stroke, which is a line that гта вайстити drawn around the гта вайстити perimeter.

A Stroke also requires a Brush that defines its appearance, and should have гта вайстити non-zero value for StrokeThickness.

StrokeThickness is a property that defines the perimeter's thickness around the shape edge. If you don't specify a Brush value for Stroke, or if you set StrokeThickness to 0, гта вайстити the border around гта вайстити shape is not drawn.

Ellipse

An Ellipse is a shape with a curved perimeter. To create a basic Ellipse, specify a Width, Height, and a Brush for the Fill.

The next гта вайстити creates an Ellipse with a Width of 200 and a Height of 200, and uses a SteelBlue colored SolidColorBrush as its Fill.

Here's the rendered Ellipse.

In this case the Ellipse is what most people would consider a circle, but that's гта вайстити you declare a circle shape in XAML: use an Ellipse with equal Width and Height.

When an Ellipse is positioned in a UI layout, its size is assumed to be the same as a rectangle with that Width and Height; the area outside the perimeter does not have rendering but still is part of its layout slot size.

A set of 6 Ellipse elements are part of the control template for the ProgressRing control, and 2 concentric Ellipse elements are part of a RadioButton.

Rectangle

A Rectangle is a four-sided shape with its opposite sides being equal.

To create a basic Rectangle, specify a Width, a Height, and a Fill.

You гта вайстити round the corners of a гта вайстити. To create rounded corners, specify a value for the RadiusX and RadiusY properties. These properties specify the x-axis and y-axis of an ellipse that defines the curve of the corners.

The maximum allowed value of RadiusX is the Width divided by two and the maximum allowed value of RadiusY is the Height divided by two.

The next example creates a Rectangle with a Width of 200 and a Height of 100.

It uses a Blue value of SolidColorBrush for its Fill and a Black value гта вайстити SolidColorBrush for its Stroke.

We set the StrokeThickness to 3. We set the RadiusX property to 50 and the RadiusY property to 10, which gives the Rectangle rounded corners.

Here's the rendered Rectangle.

Tip  There are some scenarios for UI definitions where instead of using a Rectangle, a Border might be more appropriate.

If your intention is to create a rectangle shape around other content, it might be better to use Border because it can have child гта вайстити and will automatically size around that content, rather than using the fixed dimensions for height and width like Rectangle does.

A Border also гта вайстити the option of having rounded corners if you set the CornerRadius property.

On the гта вайстити hand, a Rectangle is probably a гта вайстити choice for control composition. A Rectangle shape is seen in many control templates because it's used as a "FocusVisual" part for focusable controls. Whenever the control is in гта вайстити "Focused" visual state, this rectangle is made visible, in other states гта вайстити hidden.

Polygon

A Polygon is a shape with a boundary defined by an arbitrary number of points.

The boundary is гта вайстити by connecting a line from one point to the next, with the last point connected to the first point. The Points property defines the collection of points that make up the boundary. In XAML, you define the points with a comma-separated list.

In code-behind you use a PointCollection to define the points and you add each individual point as a Point value to the collection.

You don't need to explicitly declare the points such that the start point and end point are both specified as the same Point value.

The rendering logic for a Polygon assumes that you are defining a closed shape and will connect the end point to the start point implicitly.

The next example creates a Polygon with 4 points set to,and.

гта вайстити

It uses a LightBlue value of SolidColorBrush for its Fill, and has no value for Stroke so it has no perimeter outline.

Here's the rendered Polygon.

Tip  A Point value is often used as a type in Гта вайстити for scenarios other than declaring the vertices of shapes.

For example, a Point is part of the event data for touch events, so you can know exactly where in a coordinate space the touch action occurred. For гта вайстити info about Point and how to use it in XAML or code, see the API reference topic for Point.

Line

A Line is simply a line drawn between two points in coordinate space.

A гта вайстити ignores any value provided for Fill, because it has no interior space. For a Line, make sure to specify values for the Stroke and StrokeThickness properties, because otherwise the Line won't render.

You don't use Point values to specify a Line shape, instead you use discrete Double values for X1, Y1, X2 and Y2.

This enables minimal markup for horizontal or vertical lines. For example, defines a horizontal line that is 400 pixels long. The other X,Y properties are 0 by default, so in terms of points this XAML would draw a line from to гта вайстити. You could then use a TranslateTransform to move the entire Line, if you гта вайстити it to start at a point гта вайстити than (0,0).

Polyline

A Polyline is similar to a Polygon in that the boundary of the shape is defined by a set of points, except the last point in a Polyline is not connected to the first point.

Note   You could explicitly have an identical start point and end point in the Points set for the Polyline, but in that case you probably could have used a Polygon instead.

If you specify a Fill of a Polyline, the Fill paints the interior space of the shape, even if the start point and end point гта вайстити the Points set for the Polyline do not intersect.

If you do not specify a гта вайстити, then the Polyline is similar to what гта вайстити have rendered if you had specified several individual Line elements where the start points and end points of consecutive lines intersected.

As with a Polygon, the Points property defines гта вайстити collection of points that make up the boundary. In XAML, you define the points with a comma-separated list. In code-behind, you use a PointCollection to define the points and you add each individual point as a Point structure to the collection.

This example creates a Polyline with four points гта вайстити to,and.

A Stroke is defined but not a Fill.

Here's the rendered Polyline. Notice that the first and last points are not connected by the Stroke outline as they are in a Polygon.

Path

A Path is the most versatile Shape because you can use it to define an arbitrary geometry.

But гта вайстити this versatility comes complexity. Let's now look at how to create a basic Path in XAML.

You define the geometry of a path with the Data property. There are two techniques for setting Data:

  • You can set a string value for Data in XAML. In this form, the Path.Data value гта вайстити consuming a serialization format гта вайстити graphics.

    You typically don't text-edit this value in string form after it is first established. Instead, you use design tools that enable you to work гта вайстити a design or drawing metaphor on a surface. Then you save or export the output, and this gives гта вайстити a XAML file or XAML string fragment with Path.Data information.

  • You can set the Data property to a single Geometry object.

    This can be done in code or in XAML. That single Geometry is typically a GeometryGroup, which acts as a container that can composite multiple geometry definitions into a single object for purposes гта вайстити the object model. The most common reason for doing this is because you want to use one or more of the curves and complex shapes that can be defined as Segments values for a PathFigure, for example BezierSegment.

This example shows a Path that might have resulted from using Blend for Visual Studio to produce just a few vector shapes and then saving the result as XAML.

The total Path consists of a Bezier curve segment and a line segment. The example is mainly intended to give you some examples of what elements exist in the Path.Data serialization format and what the numbers represent.

This Data begins with the move command, indicated by "M", which establishes an absolute start point for the path.

The first segment is a cubic Bezier curve that begins гта вайстити and ends atwhich is drawn by using the two control points and гта вайстити.

This segment is indicated by the "C" гта вайстити in the Data attribute гта вайстити second segment begins with an absolute horizontal line command "H", which specifies a line drawn from the preceding subpath endpoint to a new endpoint.

Because it's a horizontal line command, the value specified is an x-coordinate.

Here's the rendered Path.

The next example shows a usage of the other technique we discussed: a GeometryGroup with a PathGeometry.

This example exercises some of the contributing geometry types that can гта вайстити used as part of a PathGeometry: PathFigure and the various elements that can be a segment in PathFigure.Segments.

Here's the rendered Path.

Using PathGeometry may be more readable than populating a Path.Data string.

On the other hand, Path.Data uses a syntax compatible with Scalable Vector Graphics (SVG) image path definitions so it may be useful for porting graphics гта вайстити SVG, or as output from a tool like Blend.

Источник: https://docs.microsoft.com/en-us/windows/uwp/design/controls-and-patterns/shapes