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kupan787 · Jun 19, 2002, 04:27 PM

I have an image in a NSImage. I want to draw it out to my window, so right now I ust call:

[myImageView setImage: myImage];

However, this will either set it up cropped, or scaled. I want to be able to set it up cropped, but have it scrollable. Somewhat like Preview does, how you can have the image in a window, and if needed, scrollbars can be used to scroll around the image.

I cant seem to find what I need to do. Would I setup a NSScrollView, and then an NSImageView inside of that? Or is there something else I would need to do? Apple made NSTextViews so nice and easy, I wonder why they didn't do the same with NSImageViews?

Thanks,
Ben

Brad Brack · Jun 19, 2002, 06:27 PM

In Interface Builder, add a Custom View (NSView), set it to your variable, then click on the custom view and choose the menu item: Layout/Make Subviews Of/Scroll View.

Does that do what you want?

kupan787 · Jun 19, 2002, 06:46 PM

<blockquote>quote:<hr />Originally posted by Brad Brack:
In Interface Builder, add a Custom View (NSView), set it to your variable, then click on the custom view and choose the menu item: Layout/Make Subviews Of/Scroll View.

Does that do what you want?<hr /></blockquote>It might be on the right track, but no go.

I changed your instructions a bit. I creadted a custom view. But then made it an NSImageView (just making it an NSView wouldn't allow me to call setImage). I then set it to my variable, and chose the menu item: Layout/Make Subviews Of/Scroll View.

When I run my app, the image goes in place, but the scrollbars don't show up even if the image is to big. The scroll bar track is there, but no scroll bar

So any more help would be appriciated on this.

kupan787 · Jun 24, 2002, 05:17 PM

*bump*

But also a question on the NSImage topic:

I read up on the compressions I can use (when I save a NSImage back out to disk as tiff), and I found the one I need:

<blockquote>quote:<hr />

NSTIFFCompressionCCITTFAX3
CCITT Fax Group 3 compression. It's for one-bit fax images sent over telephone lines.
<hr /></blockquote>However, when I do this:

<blockquote>code:<hr /><pre style="font-size:x-small; font-family: monospace;">myTiffData = [myImageToSave TIFFRepresentationUsingCompression:NSTIFFCompressi onCCITTFAX3 factor:nil];
[myTiffData writeToFile:@"/tmp/send/Output.tif" atomically:YES];</pre><hr /></blockquote>The resulting image is a full color tiff (it looks exactly like the pdf file). From my understanding, I should have gotten a 1-bit, black and white image. What went wrong? Did I read into this too much, or am I not saving it with CCITT Fax Group 3 compression? Hopefully you know a bit about this, or someoen else that is readin gthis knows about the different tiff compressions.

Thanks,
Ben

smeger · Jun 24, 2002, 06:52 PM

When you set the image, do the following:
<blockquote>code:<hr /><pre style="font-size:x-small; font-family: monospace;">[myImageView setImage: myImage];
[myImageViw: setFrameSize: [myImage size]];</pre><hr /></blockquote>

kupan787 · Jun 24, 2002, 09:06 PM

<blockquote>quote:<hr />Originally posted by smeger:
When you set the image, do the following:
<blockquote>code:<hr /><pre style="font-size:x-small; font-family: monospace;">[myImageView setImage: myImage];
[myImageViw: setFrameSize: [myImage size]];</pre><hr /></blockquote><hr /></blockquote>Sweet! Thanks, just what I needed.

Now I have one last question. I have been looking through the NSImageView docs, and then the NSView docs, and I found the print method:

print:

- (void)print

id)sender

Opens the Print panel, and if the user chooses an option other than canceling, prints the receiver and all its subviews to the device specified in the Print panel.

But it only works on NSViews, not NSImageViews. Would I need to create a NSView, draw my NSImage into it, and then call print on that NSView? Or is there some easier way of doing it?

I am looking into creating a NSView (using initWithFrame), and I see I need to make an NSRect. However the only docs on NSRect I can find are java, and I need objective-c.

The height and width of my NSView need to be [myImage size].width by [myImage size].height

Thanks,
Ben

[ 06-24-2002, 10:29 PM: Message edited by: kupan787 ]

smeger · Jun 24, 2002, 11:36 PM

NSImageView is a subclass of NSView, so it inherits NSView's methods. The "print" method should "just work."

For NSRects, check out the "Functions" section at the bottom of the table of contents for Foundation. Link is

file://Developer/Documentation/Reference/ObjC_classic/Functions/FoundationFunctions.html . The function you want is NSMakeRect.

[ 06-25-2002, 12:40 AM: Message edited by: smeger ]

kupan787 · Jun 25, 2002, 12:19 AM

<blockquote>quote:<hr />Originally posted by smeger:
NSImageView is a subclass of NSView, so it inherits NSView's methods. The "print" method should "just work."
<hr /></blockquote>I thought it would as well, but when I tired I got this error:

*** -[NSImageView print]: selector not recognized

So i just tried creating a view, and going that way, but now I get this warning in Project Builder:

<blockquote>quote:<hr />
warning: `NSView' does not respond to `print'
<hr /></blockquote>and then if I ignore it, and try and run, I get this error:

<blockquote>quote:<hr />
lockFocus sent to a view whose window is deferred and does not yet have a corresponding platform window
<hr /></blockquote>myView is not onscreen, I thought i would be able to draw to a imaginary NSView for temp purposes. Here is the code I am using, let me know if you can spot anyhting wrong with it (I cant seem to find anything):

<blockquote>code:<hr /><pre style="font-size:x-small; font-family: monospace;">NSView *myView;

myView = [[NSView alloc] initWithFrame:NSMakeRect(0,0,[originalImage size].width, [originalImage size].height)];
[myView lockFocus];
[originalImage compositeToPoint:NSZeroPoint operation:NSCompositeCopy];
[myView unlockFocus];

[myView print];</pre><hr /></blockquote>

[ 06-25-2002, 01:21 AM: Message edited by: kupan787 ]

smeger · Jun 25, 2002, 02:48 AM

You're using the "print" selector, which doesn't exist. The selector is "print:" (note the trailing colon). Here's the prototype:
<blockquote>code:<hr /><pre style="font-size:x-small; font-family: monospace;">- (void)print

id)sender</pre><hr /></blockquote>The sender parameter is the object sending the print request. You can pass whatever you'd like, but generally, you pass, duh, the sender.

You're getting the log message about lockFocus because the view needs to be associated with a window before you can lock focus on it. If you don't want it to be in a window, you'll have to set up an offscreen one. See the lockFocusIfCanDraw selector for more info.

Finally, try to get in the habit of using the NSImage draw* selectors instead of the composite* selectors. The draw* selectors honor any rotations or transformations that have been applied to your view.

kupan787 · Jun 25, 2002, 03:17 PM

<blockquote>quote:<hr />Originally posted by smeger:
When you set the image, do the following:
<blockquote>code:<hr /><pre style="font-size:x-small; font-family: monospace;">[myImageView setImage: myImage];
[myImageView: setFrameSize: [myImage size]];</pre><hr /></blockquote><hr /></blockquote>I just noticed something about this. myImage is a PDF, that is 3 pages long. Doig this sets me up with a scroller that only scrolls the first page, I don't ever see the second or third pages.

Should doing this allow me to scroll all 3 pages? Could it be that the setImage is only showing the first page?

After looking some more at the NSImage docs I see that:

<blockquote>quote:<hr />
Initializes the receiver, a newly allocated NSImage instance, with the contents of the file filename. Unlike initByReferencingFile:, this method opens filename and creates one or more image representations from its data.
<hr /></blockquote>So there is a PDF representation created I believe. Then I loked into NSPDFImageRep, and found setCurrentPage. So do I need to change the pages being displayed on my own? If so, is there a way to make it behave more like Preview does, and you can just continusly scroll from one page to the next?

Thanks,
Ben