I'm using Flying Saucer to generate PDF from HTML (so I'm using ITextRenderer, if that matters.)
I would like to simulate something like what Webkit or Gecko put in when the image cannot be found - something like an inset outline and a little broken page image.
I have determined that overriding getImageResource in the UserAgentCallback is a way to test for this condition (the image in the ImageResource will be null) but I can't figure out a nice way to render a placeholder at this point in the API.
Is there a proper way to do this? (It would be nice if this happened out of the box...)
You're on the right track here.
You want to extend UserAgentCallback with your own custom user agent functionality. It should perform almost the identical functionality of what the existing Flying Saucer implementation does, except, when an image is not found, it should return the default broken page image that you want to include.
If you're using the iTextRenderer, there is an ITextUserAgent class which you can extend for your own custom UserAgent.
To set the UserAgent, after you create the ITextRenderer, use the following code.
ITextRenderer renderer = new ITextRenderer();
renderer.getSharedContext().setUserAgentCallback(new CustomITextUserAgent(renderer.getOutputDevice()));
Related
I would like to style notifications in Vaadin Flow (19+), in Java, exactly as shown here in typescript, by assigning a theme and not setting the color of the elements (as shown in the java example). Apart the fact that setting the color is troublesome (foreground, background...) and fragile (e.g. switching to dark mode), the Java example shows setting a CSS color, I would expect to be allowed to use Lumo color variables (e.g. --lumo-success-color). Is this possible? Can anybody show an example?
You can use the addThemeVariants() method to define the variant you want to use:
Notification notification = new Notification();
notification.addThemeVariants(NotificationVariant.LUMO_PRIMARY);
The Java examples have not been moved over to the new docs site yet, you can find them here https://vaadin.com/components/vaadin-notification/java-examples/theme-variants
Is there an example of the resize function for dropzone.js? I don't really understand how it works, it says:
"Resize is the function that gets called to create the resize information. It gets the file as first parameter and must return an object with srcX, srcY, srcWidth and srcHeight and the same for trg*. Those values are going to be used by ctx.drawImage()."
But I don't really get how to use it. So far I'm resizing the images on server-side, but I'd like to do it client-side and I think this might help. Any other solutions using dropzone.js if not this one?
I believe the built-in resize function in dropzoneJS is what is used to create the thumbnail, not resize the photo client-side, per se. There might be some way you could leverage it by setting the thumbnail dimensions to what you want to save to the server, and overwriting the file being saved with the thumbnail, but I'd have to hack about for a spell to offer you any code suggestions for that.
I am currently using ImageResizer from Imazen (http://imageresizing.net/)
I want to create images with the same dimensions which is easily achieved by adding the
www.example.com/example.png?w=150&h=150
however i want to give a bgcolor to the image for background/whitespace color.
again www.example.com/example.png?w=150&h=150&bgcolor=FF00FF works perfectly.
However is there a way to make this bgcolor transparant? (ofcourse only for .png's)
I read the docs and couldn't find a plugin or basic functionality that could provide this feature. Does anyone know if (or how) this can be achieved?
Use a 6-digit hex value (RRGGBBAA) to include an alpha/transparency component.
Consider the following, I have paragraph data being sent to a view which needs to be placed over a background image, which has at the top and the bottom, fixed elements (fig1)
Fig1.
My thought was to split this into 4 labels (Fig1.example2) my question here is how I can get the text to flow through labels 1 - 4 given that label 1,2 & 3 ar of fixed height. I assumed here that label 3 should be populated prior to 4 hence the layout in the attached diagram.
Can someone suggest the best way of doing this with maybe an example?
Thanks
Wish I could help more, but I think I can at least point you in the right direction.
First, your idea seems very possible, but would involve lots of calculations of text size that would be ugly and might not produce ideal results. The way I see it working is a binary search of testing portions of your string with sizeWithFont: until you can get the best guess for what the label will fit into that size and still look "right". Then you have to actually break up the string and track it in pieces... just seems wrong.
In iOS 6 (unfortunately doesn't apply to you right now but I'll post it as a potential benefit to others), you could probably use one UILabel and an NSAttributed string. There would be a couple of options to go with here, (I haven't done it so I'm not sure which would be the best) but it seems that if you could format the page with html, you can initialize the attributed string that way.
From the docs:
You can create an attributed string from HTML data using the initialization methods initWithHTML:documentAttributes: and initWithHTML:baseURL:documentAttributes:. The methods return text attributes defined by the HTML as the attributes of the string. They return document-level attributes defined by the HTML, such as paper and margin sizes, by reference to an NSDictionary object, as described in “RTF Files and Attributed Strings.” The methods translate HTML as well as possible into structures of the Cocoa text system, but the Application Kit does not provide complete, true rendering of arbitrary HTML.
An alternative here would be to just use the available attributes, setting line indents and such according to the image size. I haven't worked with attributed strings at this level, so I the best reference would be the developer videos and the programming guide for NSAttributedString. https://developer.apple.com/library/mac/#documentation/Cocoa/Conceptual/AttributedStrings/AttributedStrings.html#//apple_ref/doc/uid/10000036-BBCCGDBG
For lesser versions of iOS, you'd probably be better off becoming familiar with CoreText. In the end you'll be rewarded with a better looking result, reusability/flexibility, the list goes on. For that, I would start with the CoreText programming guide: https://developer.apple.com/library/mac/#documentation/StringsTextFonts/Conceptual/CoreText_Programming/Introduction/Introduction.html
Maybe someone else can provide some sample code, but I think just looking through the docs will give you less of a headache than trying to calculate 4 labels like that.
EDIT:
I changed the link for CoreText
You have to go with CoreText: create your AttributedString and a CTFramesetter with it.
Then you can get a CTFrame for each of your textboxes and draw it in your graphics context.
https://developer.apple.com/library/mac/#documentation/Carbon/Reference/CTFramesetterRef/Reference/reference.html#//apple_ref/doc/uid/TP40005105
You can also use a UIWebView
I followed this nice article
http://www.lunatech-research.com/playframework-file-upload-blob
and have a perfectly working image upload solution
My questions is, if the user doesn't select any image, how do I assign a default image during save (probably stored in the server)?
if (!user.photo)
user.photo= ?;
user.save();
The one-hack that I can think of is upload the default image and see which UID "Play" stores in the /tmp directory and assign that above. Is there an elegant named* solution to this?
when I say named, I mean I want the code to look like (which means I know what I'm doing and I can also write elegant automated code if there are more than one picture)
user.photo= "images/default/male.jpg"
rather than (which means I'm just hacking and I can't extend it elegantly for a list of pictures)
user.photo= "c0109891-8c9f-4b8e-a533-62341e713a21"
Thanks in advance
The approach I have always taken is to not change the model for empty images, but instead do something in the view to show a default image, if the image does not exist. This I think is a better approach because your are corrupting your model for display purposes, which is bad practice (as you may want to be able to see all those who have not selected an image, for example).
To achieve this, in your view you can simply use the exists() method on the Blob field. The code would look like
#{if user.photo.exists()}
<img src="#{userPhoto(user.id)}">
#{/if}
#{else}
<img src="#{'public/images/defaultUserImage.jpg'}">
#{/else}
I have assumed in the above code that you are rendering the image using the action userPhoto as described in the Lunatech article.
I'd assume you can store the default image somewhere in your applications source folder and use
user.photo.set(new FileInputStream(photo), MimeTypes.getContentType(photo.getName()));
to save the data. Photo is just a File object, so you can get the reference of your default image and use it.