Can anybody tell me if it is necessary to select the text in a PDF file loaded within a UIWebView, or is it selected on its own?
If it's not selected, how can we implement the selection of text within such a PDF?
The UIWebView actually draws the PDF pages as images so you don't have access to individual items (textfields, images etc.)
Highlighting isn't by far a trivial task. One solution would be to use the CGPDFScanner to parse the page's stream and figure out how to concatenate the transformations for the text operators (TJ, Tj, Tm, Tc, Tw etc.) in order to get the individual glyph positions. If you succeed in doing that the rest should be pretty straight forward.
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I am trying to create a program that displays pdfs in chunks. So if you have a 100 page pdf and you only want to display the first chapter you could code something for only showing pages 1 - 10. I've searched around and as it stands it seems this is the best way to display pdfs. The problem is this loads the entire pdf at once in a reader. Going through the documentation now and I can't find anyway to selectively display the pdf. is there a way to selectively display pdf text using pdfkit? or will I have to use some other library for that?
I also see there's a tabViewStyle(.page) I can use to get a paged reader view in swiftui but I'd prefer not to have to format and prettify the text if possible.
I'm not opposed to using 3rd party libraries I just don't want to have to deal with formatting text or whatever. thanks!
My Desktop App is creating a single page pdf with itextsharp library.There are 40 Passport size photos with names under it on a single page.
I need to flatten this pdf page (with 40 photos) as one Image while creating the pdf,currently there are 40 individual photos on the pdf page.I presume it would create around 80 layers by default which would take a very high time on ripping this file for printing on a press.
I dont want to make all the 40 images as one jpeg externally using GDI+ and then lay it in pdf.
I have seen many options using stamper and reading the created pdf file to flatten.Is there a way while creating the pdf i can create a flattened file.
Your understanding of flattening a PDF is completely wrong. The concept of flattening a PDF means: removing all interactivity. For instance: you have a PDF file with form fields. The content of these form fields can be changed in Adobe Reader. When you flatten such a form, you take away the form fields and replace the field content by actual content of the page. The result is a flat PDF in the sense that people can no longer change the content of the fields.
You presume that having multiple pictures on a single page in a PDF means that there are multiple layers in that PDF. Your understanding of layers in a PDF is completely wrong. Layers is a word that is used in many different contexts. For instance, when working with optional content groups (OCG), people often refer to layers.
The concept of layers as you may know it from Photoshop doesn't really exist in PDF. Content is added in a stream. Whatever content is added first, can be covered by content that comes after. You want to pro-process the content by removing all the content that isn't visible in the hope that the PDF will be printed faster. You want to achieve that by replacing many different image objects by one image.
Your assumption that this can be done with iText is wrong. iText doesn't convert PDF to an image. This is outside the scope of what iText is written for.
If you want to add X images as 1 single image using iText, then you have to process the X images into 1 single image before you add the images to the PDF. You need image manipulation software, because iText won't do what you're asking for.
I have a requirement to add few lines at the top of an existing PDF.
I have done this using a PdfReader and a PdfStamper.
In order to have more space in the page header area, i need to move down the current contents by 1 or 2 lines.
Below is from the forum. but it doesn't solve the issue.
How to insert content in the middle of a page in a PDF using IText
Any suggestions?
-i can not upload the pdf or the image of the pdf because am a new user
Do I interpret your question correctly if I assume that you really want to move down everything on the page and add some lines above?
You can do that by changing the media box (and crop box and what other boxes might be explicitly defined for your page) and then add the few lines on top the same way you already do it now.
You can access those boxes in the respective page dictionary which you can retrieve via the PdfReader. Look up the PDF specification for details on those boxes.
Or do I interpret you incorrectly and you only want to move down some text while keeping existing headers and footers in place? In that case Alexis' answer to the other question you refer to still holds.
I'm writing an iPad app where the user will open PDF documents.
I want to substitute some unique texts with clickable buttons.
ie. if there is a text: "Please click a button" I want to put a button instead (or over) the word "button".
What is the right way to do this?
Thanks!
There is not a straight forward solution to it. What you need to do is following :
1) Search for text 'button'. PDF document text extraction needs to happen before this. Performace depends on how you do this. Some PDF parsers create a marker and while rendering the PDF it indexes the text data of PDF. So searching becomes faster. There can be many more approaches :)
2) Get the bounding box coordinates of the text in screen space.
2) Now draw a platform widget on this coordinate.
I have about twenty UITextViews and corresponding .txt files. What I want is to make each UITextView take the contents of the corresponding file and display it.
Moreover, the text is formatted and it contains some formulas (copy/pasted from Grapher). I've heard about displaying formatted text in UIWebView, but I haven't found a clear explanation anywhere.
Thanks in advance!
Text files normally don't contain formatted text.
If by "formatted" you mean "html" then yes, you will want to use UIWebView. Basically you will convert the text to an HTML document, and then use the web view to display that document. There are several example projects available from Apple that show you how to use UIWebView.
Displaying formula in a UITextView will be difficult as the character rules for formula are completely different from language text. You could generate HTML to display it that but that is difficult as well.
I think your best bet would be to draw the formula to an image and then display the image. That is the traditional way to handle the display of formula.