In the next example, you’ll put the page number in the header, and you’ll add the total number of pages. Consider it more safe to reserve the onEndPage() method for adding content. If you add content in an onStartPage() method, there’s always a risk of having unwanted pages. It’s important that it’s ignored for empty pages otherwise you’d end up with plenty of unwanted new pages that are unintentionally left blank. This method is executed-or ignored-when you call it explicitly from your code, but it’s also invoked implicitly from within iText on multiple occasions. Otherwise, the getBoxSize() method will return null.įAQ Why is it not advised to add content in the onStartPage() method? You’ll remember from section 5.2.4 that iText ignores newPage() calls when the current page is empty.
#Pdfwriter example pdf
This will only work if you’ve defined that specific page boundary between steps 2 and 3 in the PDF creation process. You use this rectangle to position the header and the footer. Note that you ask the writer for the art box rectangle using the getBoxSize() method. The parameters writer and document are to be used in the same way as done in section 5.2. The header and footer are written to the direct content in the onEndPage() method.
No content is added in the page event until a page has been completed. It’s augmented in the onStartPage() method. ■ pagenumber-A custom page number that is reset to 1 every time a new topic starts. The other varies depending on the current topic.
#Pdfwriter example full
One is set in onOpenDocument(), and it’s valid for the full document. ■ header-An array with two Phrase objects.
#Pdfwriter example code
There are no surprises in this code sample. For instance, setting the art box doesn’t affect the page margins.įigure 5.11 Adding headers and footers using page events Setting these boundaries doesn’t have any effect on the way iText creates the document. These values are important primarily for the PDF consumer. The following implementation of the PdfPageEvent interface meets these requirements. As for the header, you want it to alternate between the topic title aligned to the left, and the String "Movie history" aligned to the right. The text should be put under the actual content of the page, as a centered String. This event, an instance of the HeaderFooter class, will add a header and a footer to the document as shown in figure 5.11.įirst, take a look at the footer: you want to add page numbers that start with "page 1" every time a new topic begins. You’ll make two small changes: you’ll define an art box, and you’ll add an event to the writer. Let’s return to the topic and Section example from section 2.3.2. For instance, how can you add a page header while creating a PDF document. Let’s use these methods to solve common issues that are often mentioned in mailing-list questions. This is the ideal place for any finalizations and to release resources (if necessary). ■ onCloseDocument() -Triggered just before the document is closed. This is the best place to add a header, a footer, a watermark, and so on.
■ onEndPage() -Triggered just before starting a new page and before closing the document. Use this method for initializing variables or for setting parameters that are page-specific. ■ onStartPage() -Triggered when a new page is started. This is a good place to initialize variables that will be needed throughout the document. ■ onOpenDocument() -Triggered when a document is opened. We have already discussed seven methods of the PdfPageEvent interface four more methods involving the document and its pages remain: After the intermezzo about page boundaries, containing some self-glorifying examples, it’s time to return to the real topic of this topic: page events.
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