Platzieren von Bildern in einem XPS-OM
Beschreibt, wie Bilder in einem XPS-OM platziert werden.
Um Bilder in einem XPS-OM zu platzieren, erstellen Sie ein Pfadobjekt, das die Position und den Umriss eines Bildes definiert, und verwenden Sie dann einen Bildpinsel, um den Pfad zu füllen. Fügen Sie das erstellte Pfadobjekt zur Liste der visuellen Objekte der Seite oder des Zeichenbereichs hinzu, damit es mit dem anderen visuellen Inhalt gerendert werden kann.
Bevor Sie diese Codebeispiele in Ihrem Programm verwenden, lesen Sie den Haftungsausschluss in Allgemeine XPS-Dokumentprogrammierungsaufgaben.
Codebeispiel
Erstellen einer Bildressource
Wenn das Quellbild im XPS-OM nicht als Bildressource verfügbar ist, erstellen Sie zuerst die Bildressource:
HRESULT hr = S_OK;
IStreamPtr imageStream; // the resulting image stream
IOpcPartUri *imagePartUri;
IXpsOMImageResource *imageResource;
XPS_RECT rect = {0.0f, 0.0f, 0.0f, 0.0f}; // set to image size
hr = xpsFactory->CreateReadOnlyStreamOnFile (
imageFileName, &imageStream );
hr = xpsFactory->CreatePartUri( imagePartName, &imagePartUri );
imageType; // set to type of image being read in
hr = xpsFactory->CreateImageResource (
imageStream,
imageType,
imagePartUri,
&imageResource);
imagePartUri->Release();
imageStream->Release();
// imageResource can now be used by other parts in the XPS OM.
Platzieren des Bilds in die visuelle Sammlung
Wenn das Quellbild im XPS-OM als Bildressource verfügbar ist, kann es zum Erstellen eines Bildpinselobjekts verwendet und als Füllpinsel zum Pfad hinzugefügt werden, der die Position und Größe des Bildes auf der Seite angibt.
// These variables are initialized outside of this code example,
// for example, as the parameters of a method or from some
// preceding program code.
// dimensions of the image in pixels
XPS_SIZE bmpDim = {0,0} ;
// DPI resolution values obtained from image
FLOAT dpiX = 96.0f;
FLOAT dpiY = 96.0f;
// initialize viewport values
XPS_RECT viewPort = {0.0,0.0,0.0,0.0};
// initialize viewbox values
XPS_RECT viewBox = {0.0,0.0,0.0,0.0};
// These are part of this code example.
IXpsOMPath *imageRectPath;
IXpsOMImageBrush *imageBrush;
IXpsOMVisualCollection *pageVisuals;
// Describe image source dimensions and set viewbox to be the
// entire image DIP width of image.
// Example:
// 600 image pixels, 300 dpi -> 2 inches -> 2 * 96 = 192 DIP width
viewBox.width = FLOAT((double)bmpDim.width * 96.0 / dpiX);
viewBox.height = FLOAT((double)bmpDim.height * 96.0 / dpiY);
// Describe the size and position of the image destination.
// rect is an XPS_RECT structure that is initialized outside
// of this sample for example, it might be passed in as a parameter.
// destination rectangle
viewPort.x = rect.x;
viewPort.y = rect.y;
viewPort.width = rect.width;
viewPort.height = rect.height;
// Create the image brush.
hr = xpsFactory->CreateImageBrush(imageResource, &viewBox, &viewPort,
reinterpret_cast<IXpsOMImageBrush**>(&imageBrush));
// Create the path that describes the outline of the image on the page.
// This step uses the function described in the next code example.
hr = CreateRectanglePath(xpsFactory, &rect,
reinterpret_cast<IXpsOMPath**>(&imageRectPath));
// Set the accessibility description for the path object as required.
hr = imageRectPath->SetAccessibilityShortDescription( shortDescText );
// Set the image brush to be the fill brush for this path.
hr = imageRectPath->SetFillBrushLocal( imageBrush );
// Get the list of visuals for this page...
hr = xpsPage->GetVisuals( &pageVisuals );
// ...and add the completed path to the list.
hr = pageVisuals->Append( imageRectPath );
// Release locally created interfaces.
if (NULL != pageVisuals) pageVisuals->Release();
if (NULL != imageRectPath) imageRectPath->Release();
if (NULL != imageBrush) imageBrush->Release();
Erstellen eines Pfadobjekts für das Bild
Die folgende Methode akzeptiert eine XPS_RECT Struktur und erstellt einen rechteckigen Pfad.
HRESULT
CreateRectanglePath(
__in IXpsOMObjectFactory *xpsFactory,
__in const XPS_RECT *rect,
__out IXpsOMPath **rectPath
)
{
HRESULT hr = S_OK;
IXpsOMGeometryFigure *rectFigure;
IXpsOMGeometry *imageRectGeometry;
IXpsOMGeometryFigureCollection *geomFigureCollection;
// Define start point and three of the four sides of the rectangle.
// The fourth side is implied by setting the path type to CLOSED.
XPS_POINT startPoint = {rect->x, rect->y};
XPS_SEGMENT_TYPE segmentTypes[3] = {
XPS_SEGMENT_TYPE_LINE,
XPS_SEGMENT_TYPE_LINE,
XPS_SEGMENT_TYPE_LINE
};
FLOAT segmentData[6] = {
rect->x, rect->y+rect->height,
rect->x+rect->width, rect->y+rect->height,
rect->x+rect->width, rect->y
};
BOOL segmentStrokes[3] = {
TRUE, TRUE, TRUE
};
// Create a closed geometry figure using the three
// segments defined above.
hr = xpsFactory->CreateGeometryFigure( &startPoint, &rectFigure );
hr = rectFigure->SetIsClosed( TRUE );
hr = rectFigure->SetIsFilled( TRUE );
hr = rectFigure->SetSegments( 3, 6,
segmentTypes, segmentData, segmentStrokes );
// Create a geometry that consists of the figure created above.
hr = xpsFactory->CreateGeometry( &imageRectGeometry );
hr = imageRectGeometry->GetFigures( &geomFigureCollection );
hr = geomFigureCollection->Append( rectFigure );
// Create the path that consists of the geometry created above
// and return the pointer in the parameter passed in to the function.
hr = xpsFactory->CreatePath( reinterpret_cast<IXpsOMPath**>(rectPath) );
hr = (*rectPath)->SetGeometryLocal( imageRectGeometry );
// The calling method will release these interfaces when
// it is done with them.
return hr;
}
Zugehörige Themen
-
Nächste Schritte
-
Wird auf dieser Seite verwendet
-
Weitere Informationen