| public static FreezeIfFreezable ( System.Windows.Freezable freezable ) : System.Boolean | ||
| freezable | System.Windows.Freezable | |
| Результат | System.Boolean | |
GetPathGeometryFromPathSegments
(
Point oStartPoint,
Boolean bPathFigureIsFilled,
params PathSegment[] aoPathSegments
)
{
Debug.Assert(aoPathSegments != null);
PathFigure oPathFigure = new PathFigure();
oPathFigure.StartPoint = oStartPoint;
oPathFigure.IsFilled = bPathFigureIsFilled;
PathSegmentCollection oSegments = oPathFigure.Segments;
foreach (PathSegment oPathSegment in aoPathSegments)
{
WpfGraphicsUtil.FreezeIfFreezable(oPathSegment);
oSegments.Add(oPathSegment);
}
WpfGraphicsUtil.FreezeIfFreezable(oPathFigure);
PathGeometry oPathGeometry = new PathGeometry();
oPathGeometry.Figures.Add(oPathFigure);
WpfGraphicsUtil.FreezeIfFreezable(oPathGeometry);
return(oPathGeometry);
}
ResizeImage
(
BitmapSource image,
Int32 widthNew,
Int32 heightNew
)
{
Debug.Assert(image != null);
Debug.Assert(widthNew > 0);
Debug.Assert(heightNew > 0);
AssertValid();
// The following code was adapted from this post:
//
// http://chironexsoftware.com/blog/?p=55
TransformedBitmap resizedImage = new TransformedBitmap(image,
new ScaleTransform(
(Double)widthNew / (Double)image.PixelWidth,
(Double)heightNew / (Double)image.PixelHeight,
0, 0)
);
WpfGraphicsUtil.FreezeIfFreezable(resizedImage);
return(resizedImage);
}
GetImageSynchronousHttp
(
Uri uri
)
{
Debug.Assert(uri != null);
Debug.Assert(
uri.Scheme == Uri.UriSchemeHttp
||
uri.Scheme == Uri.UriSchemeHttps
);
AssertValid();
String sTemporaryFilePath =
GetTemporaryFilePathForDownloadedImage(uri);
try
{
// Download the file using a simple synchronous technique.
(new WebClient()).DownloadFile(uri, sTemporaryFilePath);
BitmapImage oBitmapImage = new BitmapImage();
oBitmapImage.BeginInit();
oBitmapImage.CacheOption = BitmapCacheOption.OnLoad;
// Some Twitter images have corrupted color profiles, which causes
// BitmapImage.EndInit() to raise an ArgumentException with the
// message "Value does not fall within the expected range." Follow
// the suggestion at the following page and ignore color profiles.
//
// http://www.hanselman.com/blog/
// DealingWithImagesWithBadMetadataCorruptedColorProfilesInWPF.aspx
oBitmapImage.CreateOptions =
BitmapCreateOptions.IgnoreColorProfile;
// Synchronously load the bitmap with the contents of the
// downloaded file.
using (FileStream oFileStream =
new FileStream(sTemporaryFilePath, FileMode.Open))
{
oBitmapImage.StreamSource = oFileStream;
oBitmapImage.EndInit();
}
WpfGraphicsUtil.FreezeIfFreezable(oBitmapImage);
return(oBitmapImage);
}
finally
{
File.Delete(sTemporaryFilePath);
}
}
GetImageSynchronousIgnoreDpi
(
String uriString
)
{
Debug.Assert(!String.IsNullOrEmpty(uriString));
AssertValid();
BitmapSource oBitmapSource = GetImageSynchronous(uriString);
if (oBitmapSource.DpiX != m_dScreenDpi)
{
// The DPI properties of BitmapSource are read-only. To work
// around this, copy the BitmapSource to a new BitmapSource,
// changing the DPI in the process. Wasteful, but there doesn't
// seem to be a better way.
// The formula for stride, which isn't documented in MSDN, was
// taken from here:
//
// http://social.msdn.microsoft.com/Forums/en/windowswic/thread/
// 8e2d2dbe-6819-488b-ac49-bf5235d87bc4
Int32 iStride = ((oBitmapSource.PixelWidth *
oBitmapSource.Format.BitsPerPixel) + 7) / 8;
// Also, see this:
//
// http://social.msdn.microsoft.com/Forums/en-US/wpf/thread/
// 56364b28-1277-4be8-8d45-78788cc4f2d7/
Byte [] abtPixels = new Byte[oBitmapSource.PixelHeight * iStride];
oBitmapSource.CopyPixels(abtPixels, iStride, 0);
oBitmapSource = BitmapSource.Create(oBitmapSource.PixelWidth,
oBitmapSource.PixelHeight, m_dScreenDpi, m_dScreenDpi,
oBitmapSource.Format, oBitmapSource.Palette, abtPixels, iStride
);
WpfGraphicsUtil.FreezeIfFreezable(oBitmapSource);
}
return(oBitmapSource);
}
DrawingVisualToRenderTargetBitmap
(
DrawingVisual oDrawingVisual,
Int32 iWidth,
Int32 iHeight
)
{
Debug.Assert(oDrawingVisual != null);
Debug.Assert(iWidth > 0);
Debug.Assert(iHeight > 0);
AssertValid();
RenderTargetBitmap oRenderTargetBitmap = new RenderTargetBitmap(
iWidth, iHeight, 96.0, 96.0, PixelFormats.Pbgra32);
oRenderTargetBitmap.Render(oDrawingVisual);
WpfGraphicsUtil.FreezeIfFreezable(oRenderTargetBitmap);
return(oRenderTargetBitmap);
}
GetQuadraticBezierCurve
(
Point startPoint,
Point endPoint,
Point controlPoint
)
{
QuadraticBezierSegment oQuadraticBezierSegment =
new QuadraticBezierSegment(controlPoint, endPoint, true);
PathFigure oPathFigure = new PathFigure();
oPathFigure.StartPoint = startPoint;
oPathFigure.Segments.Add(oQuadraticBezierSegment);
PathGeometry oQuadraticBezierCurve = new PathGeometry();
oQuadraticBezierCurve.Figures.Add(oPathFigure);
WpfGraphicsUtil.FreezeIfFreezable(oQuadraticBezierCurve);
return(oQuadraticBezierCurve);
}
GetPathGeometryFromPoints
(
System.Windows.Point startPoint,
params Point [] otherPoints
)
{
Debug.Assert(otherPoints != null);
Int32 iOtherPoints = otherPoints.Length;
Debug.Assert(iOtherPoints > 0);
PathFigure oPathFigure = new PathFigure();
oPathFigure.StartPoint = startPoint;
PathSegmentCollection oPathSegmentCollection =
new PathSegmentCollection(iOtherPoints);
for (Int32 i = 0; i < iOtherPoints; i++)
{
oPathSegmentCollection.Add(
new LineSegment(otherPoints[i], true));
}
oPathFigure.Segments = oPathSegmentCollection;
oPathFigure.IsClosed = true;
WpfGraphicsUtil.FreezeIfFreezable(oPathFigure);
PathGeometry oPathGeometry = new PathGeometry();
oPathGeometry.Figures.Add(oPathFigure);
WpfGraphicsUtil.FreezeIfFreezable(oPathGeometry);
return(oPathGeometry);
}
GetImageSynchronous
(
String uriString
)
{
Debug.Assert(!String.IsNullOrEmpty(uriString));
AssertValid();
const Int32 ErrorImageWidthAndHeight = 52;
Uri oUri;
if (Uri.TryCreate(uriString, UriKind.Absolute, out oUri))
{
if (oUri.Scheme == Uri.UriSchemeHttp ||
oUri.Scheme == Uri.UriSchemeHttps)
{
try
{
return(GetImageSynchronousHttp(oUri));
}
catch (WebException)
{
// (These empty catch blocks cause an error image to be
// returned.)
}
catch (ArgumentException)
{
/*
* Attempting to download a possibly corrupt image from this
* Twitter URL:
*
* http://a1.twimg.com/profile_images/1112245377/
* Photo_on_2010-08-27_at_18.51_normal.jpg
*
* raised the following exception:
*
* [ArgumentException]: An invalid character was found in text
* content.
* at System.Windows.Media.Imaging.BitmapFrameDecode.
* get_ColorContexts()
* at System.Windows.Media.Imaging.BitmapImage.
* FinalizeCreation()
* at System.Windows.Media.Imaging.BitmapImage.EndInit()
*/
}
catch (FileFormatException)
{
/*
* A user attempted to download a possibly corrupt image from
* Twitter on 5/6/2011. The exact URL wasn't determined.
*
* The following exception was raised:
*
* [FileFormatException]: The image format is unrecognized.
* [COMException]: Exception from HRESULT: 0x88982F07 at
* System.Windows.Media.Imaging.BitmapDecoder.
* SetupDecoderFromUriOrStream(Uri uri, Stream stream,
* BitmapCacheOption cacheOption, Guid& clsId, Boolean&
* isOriginalWritable, Stream& uriStream,
* UnmanagedMemoryStream& unmanagedMemoryStream,
* SafeFileHandle& safeFilehandle)
*/
}
catch (IOException)
{
/*
* Attempting to download a possibly corrupt image from this
* Twitter URL:
*
* http://a2.twimg.com/profile_images/1126755034/
* 8FjbVD_normal.gif
*
* raised the following exception:
*
* [IOException]: Cannot read from the stream.
* [COMException]: Exception from HRESULT: 0x88982F72
* at System.Windows.Media.Imaging.BitmapDecoder.
* SetupDecoderFromUriOrStream(Uri uri, Stream stream,
* BitmapCacheOption cacheOption, Guid& clsId, Boolean&
* isOriginalWritable, Stream& uriStream,
* UnmanagedMemoryStream& unmanagedMemoryStream,
* SafeFileHandle& safeFilehandle)
* ...
*/
}
catch (NotSupportedException)
{
/*
* Attempting to download a possibly corrupt image from a
* Twitter URL (didn't record the URL) raised the following
* exception:
*
* [NotSupportedException]: No imaging component suitable
* to complete this operation was found.
*/
}
}
else if (oUri.Scheme == Uri.UriSchemeFile)
{
try
{
// This is a synchronous operation.
BitmapImage oBitmapImage = new BitmapImage(oUri);
WpfGraphicsUtil.FreezeIfFreezable(oBitmapImage);
return(oBitmapImage);
}
catch (IOException)
{
}
catch (ArgumentException)
{
// This occurs when the URI contains an invalid character,
// such as "<".
}
catch (WebException)
{
// This occurs when a non-existent drive letter is used.
}
catch (NotSupportedException)
{
// Invalid image file.
}
catch (UnauthorizedAccessException)
{
// The URI is actually a folder, for example.
}
}
}
if (m_oCachedErrorImage == null)
{
m_oCachedErrorImage = CreateErrorImage(ErrorImageWidthAndHeight);
}
return(m_oCachedErrorImage);
}
