Busy Developers' Guide to HSLF drawing layer

Busy Developers' Guide to HSLF drawing layer +

Index of Features +

How to create a new presentation and add new slides to it
How to retrieve or change slide size
How to get shapes contained in a particular slide
Drawing a shape on a slide
How to add/retrieve pictures

Features + +

New Presentation + + //create a new empty slide show + SlideShow ppt = new SlideShow(); + + //add first slide + Slide s1 = ppt.createSlide(); + + //add second slide + Slide s2 = ppt.createSlide(); + + //save changes in a file + FileOutputStream out = new FileOutputStream("slideshow.ppt"); + wb.write(out); + out.close(); + +

+ +

How to retrieve or change slide size + + SlideShow ppt = new SlideShow(new HSLFSlideShow("slideshow.ppt")); + //retrieve page size. Coordinates are expressed in points (72 dpi) + java.awt.Dimension pgsize = ppt.getPageSize(); + int pgx = pgsize.width; //slide width + int pgy = pgsize.height; //slide height + + //set new page size + ppt.setPageSize(new java.awt.Dimension(1024, 768)); + //save changes + FileOutputStream out = new FileOutputStream("slideshow.ppt"); + wb.write(out); + out.close(); + +

+ +

How to get shapes contained in a particular slide +

The superclass of all shapes in HSLF is the Shape class - the elemental object that composes a drawing. + The following pictute shows the class tree of HSLF shapes: +

+ Class Tree of HSLF Shapes +

+ The following fragment demonstrates how to iterate over shapes for each slide. +

+ + SlideShow ppt = new SlideShow(new HSLFSlideShow("slideshow.ppt")); + //get slides + Slide[] slide = ppt.getSlides(); + for (int i = 0; i < slide.length; i++){ + Shape[] sh = slide[i].getShapes(); + for (int j = 0; j < sh.length; j++){ + //name of the shape + String name = sh[j].getShapeName(); + + //shapes's anchor which defines the position of this shape in the slide + java.awt.Rectangle anchor = sh[j].getAnchor(); + + if (sh[j] instanceof Line){ + Line line = (Line)sh[j]; + //work with Line + } else if (sh[j] instanceof AutoShape){ + AutoShape shape = (AutoShape)sh[j]; + //work with AutoShape + } else if (sh[j] instanceof TextBox){ + TextBox shape = (TextBox)sh[j]; + //work with TextBox + } else if (sh[j] instanceof Picture){ + Picture shape = (Picture)sh[j]; + //work with Picture + } + } + } + +

+ +

Drawing a shape on a slide +

+ When you add a shape, you usually specify the dimensions of the shape and the position + of the upper left corner of the bounding box for the shape relative to the upper left + corner of the slide. Distances in the drawing layer are measured in points (72 points = 1 inch). +

+ + SlideShow ppt = new SlideShow); + + Slide slide = ppt.createSlide(); + + //Line shape + Line line = new Line(); + line.setAnchor(new java.awt.Rectangle(50, 50, 100, 20)); + line.setLineColor(new Color(0, 128, 0)); + line.setLineStyle(Line.LineDashDotSys); + slide.addShape(line); + + //TextBox + TextBox txt = new TextBox(); + txt.setText("Hello, World!"); + txt.setAnchor(new java.awt.Rectangle(100, 100, 200, 50)); + txt.setFontSize(32); + txt.setFontName("Arial"); + txt.setBold(true); + slide.addShape(txt); + + //Autoshape + //32-point star + AutoShape sh1 = new AutoShape(ShapeTypes.Star32); + sh1.setAnchor(new java.awt.Rectangle(50, 50, 100, 200)); + sh1.setFillColor(Color.red); + slide.addShape(sh1); + + //Trapezoid + AutoShape sh2 = new AutoShape(ShapeTypes.Trapezoid); + sh2.setAnchor(new java.awt.Rectangle(150, 150, 100, 200)); + sh2.setFillColor(Color.blue); + slide.addShape(sh2); + + FileOutputStream out = new FileOutputStream("slideshow.ppt"); + wb.write(out); + out.close(); + +

+ +

How to add/retrieve pictures +

+ Note, for now only PNG and JPEG formats are supported. +

+ + SlideShow ppt = new SlideShow(new HSLFSlideShow("slideshow.ppt")); + + //extract all pictures contained in the presentation + PictureData[] pdata = ppt.getPictureData(); + for (int i = 0; i < pdata.length; i++){ + PictureData pict = pdata[i]; + + //raw picture data + byte[] data = pict.getData(); + + int type = pict.getType(); + if (type == Picture.JPEG){ + FileOutputStream out = new FileOutputStream("pict"+i+".jpg"); + out.write(data); + out.close(); + } else if (type == Picture.PNG){ + FileOutputStream out = new FileOutputStream("pict"+i+".png"); + out.write(data); + out.close(); + } + } + + // add a new picture to this slideshow and insert it in a new slide + int idx = ppt.addPicture(new File("clock.jpg"), Picture.JPEG); + + Picture pict = new Picture(idx); + + //set image position in the slide + pict.setAnchor(new java.awt.Rectangle(100, 100, 300, 200)); + + Slide slide = ppt.createSlide(); + slide.addShape(pict); + + //now retrieve pictures containes in the first slide and save them on disk + slide = ppt.getSlides()[0]; + Shape[] sh = slide.getShapes(); + for (int i = 0; i < sh.length; i++){ + if (sh[i] instanceof Picture){ + Picture pict = (Picture)sh[i]; + PictureData data = pict.getPictureData(); + byte[] data = pict.getData(); + int type = pict.getType(); + if (type == Picture.JPEG){ + FileOutputStream out = new FileOutputStream("slide0_"+i+".jpg"); + out.write(data); + out.close(); + } else if (type == Picture.PNG){ + FileOutputStream out = new FileOutputStream("slide0_"+i+".png"); + out.write(data); + out.close(); + } + } + } + + FileOutputStream out = new FileOutputStream("slideshow.ppt"); + wb.write(out); + out.close(); + + +