Hey guys, I've just migrated my image selector from NSCollectionView to IKImageBrowserView. I've got almost everything set up the way I want it, except for the selection ring. I don't like the greyed out background that IKImageBrowserView defaults to, and I wanted to do a yellow stroke around the edge of my selected image to indicate it's selection (like in iPhoto). Is is possible to override the draw state of IKImageBrowserCell? I haven't been able to find any way to do it yet. It doesn't have the simple drawRect methods that I'm used to. Any help would be appreciated. I'm assuming I have to use CALayers?
I overrode - (CALayer *)layerForType:(NSString *)type and tried just as a test, setting the layer corner radius to 0, but it didn't seem to change anything. The method is being called because if I throw a breakpoint in it, it stops there. However, even if I return nil from that method, it still draws the images like usual.
Thanks!
That is the right method for customizing the IKImageBrowserCell.
Using CALayers and configuring different attributes, you can control many facets of how the images are presented.,
A layer of type = IKImageBrowserCellSelectionLayer is what you will want to change to have the display behave and present as you wish.
Here's a link to Apple's sample code project that will get you started
Related
I have been trying to create a simple swipe transition. However buttons seem immune to any CAAnimation that crops.
I am trying to get it so that a bar moves across the screen and as it goes over the button it removes the part it has just gone over.
I have tried bounds.width, size.x and many other key-value paths to achieve the affect but I haven't got what I wanted. It just relocates the text which always remains entirely visible
I have also tried changing the UIButton to a UIImage but the text does not seem to print on a UIImage.
I tried using masks too but I have heard they should be used as infrequently as possible as they consume the phones resources. I didn't really get very far with this either anyway as I hadn't used them much before.
I also tried placing it in a container view and then change the dimensions of that but again all of the text remained entirely visible.
I know I could have a view hide the button but I am trying to reveal the view behind as the bar swipes.
Does anyone have any suggestions of how to achieve a swipe transition on a UIButton?
Help would be much appreciated.
Thanks
I think what you're looking for really is a mask. See the tutorial here:
http://iosdevelopertips.com/cocoa/how-to-mask-an-image.html
What I'd do in your situation is create a custom UIButton class, and add a mask as in the tutorial, then animate the position of the mask. Slide the mask of, nothing shows. Slide it on, part shows until the whole thing is visible.
Edit: I haven't really heard anything about hogging resources, especially since it appears to be simple core graphics.
I am trying to create a view for a kind of brainstorming application like, for example, OmniGraffle, with elements that contain textviews and can be dragged around. (Also, the should be connectable with arrows, but that is not (yet) the problem)
I did my homework and searched via google and read books about cocoa, but there seems to be no similar example around.
Since I am also new to cocoa, I’m a bit helpless here.
The thing I am sure of is, that I need a custom view in which I can create my elements - what I tried until now to do that is:
First, I searched for the syntax to add subwindows to a window to create my elements. Subwindows, I imagined, would automatically be movable and come to front and so on.
The problem: As the experienced Cocoa-programmers of you probably are not surprised, I was stunned to find nothing about anything like that - this seems to be something, that is just not intended in Cocoa?!
Then I thought about creating subviews that contain a custom view for the title bar drawing (where the user can click to drag the element) and a NSTextView.
Problems:
I read, that it is not so clever to create dozens of subviews in a window because that would be very slow (or would that be not so bad in this case because all the subviews would be instances of always the same class?).
Also I can’t find out how to load a subview from a nib- or xib-file. Would I need a viewController? Or would that make the dozens-of-instances-problem even worse?
And Apple tells you not to overlap subviews (okay, that would be not so important, but I really wonder how the guys at OmniGroup made OmniGraffle...)
Because of that, I now wanted to do the title-bar-drawing in the surrounding custom view and create the textview programmatically (as I understand, a text-“view“ ist not really a view and takes its functionality from NSCell to reduce all the effort with the views?).
Problems:
Even that failed because I was not able to create a textview that doesn’t fill the complete window (the initWithFrame: of the [[NSScrollView alloc] initWithFrame: aRect] just seems to be ignored or do I get that wrong?).
Also, there should be some buttons on each element in the final application. I imagine that would be easier to accomplish with a subview from a nib-file for each element?
Well, now that nothing works and the more I read, the more problems seem to occur, I am pretty confused and frustrated.
How could I realize such a program? Could someone please push me in the right direction?
I created a class for the draggable elements where I save position, size and text in instance variables. In my view, every new element instance is added to an array (for now, this works without a controller). The array is used to draw all the elements in a loop in drawRect:. For the text of the element I just use a NSTextFieldCell which is set to the saved text from every element in the same loop.
That way it is also possible to overlap the elements.
I have an instance of NSImageView. I have told InterfaceBuilder to allow the user to paste or drag an image into this view. This works. However, I don't see a way in the NSImageView or related documentation to get notified when this actually happens. I was expecting a delegate or some such, but I have been unable to find it. Any ideas?
This is what Cocoa Bindings does best.
Instead of talking to the view, simply have a property whose value is an image, and bind the image view's image binding to it; then, when you want to change the image in the image view yourself, all you have to do is set the value of the property, and the image view will notice the change.
The user pasting or dragging into the image view is essentially the same thing, partly in reverse: The paste or drop will change the value of the image view, which will then set the value of your property, which will cause anything else bound to it to notice the change and pick up the new value as before.
Aside from ripping out your existing send-explicit-messages-to-views code, this will require almost no code work: The only code you need is for your property. You'll hook up the Binding in IB.
See the Key-Value Coding Programming Guide and the Cocoa Bindings Programming Topics.
As for me the better way to override function
-(void)paste:(id)sender
But only if you have it in NSView based class which has NSResponder as parent
I have a custom NSPopUpButtonCell and I'm trying to override drawImage:withFrame:inView. Strangely, the drawImage method is never called, but the image appears on screen. What am I missing?
I've checked to make sure my cell is properly installed -- I am getting drawWithFrame:inView:controlView messages.
Note that I'm trying to compensate for an image only gradient-style button not properly centering it's image (it's 1 pixel to the left of where it should be).
NSPopupButtonCell inherits from NSMenuCell and NSMenuCell has a method called drawImageWithFrame:inView: which might be what you're looking for. It has several other drawing methods too so check those and see which one is being called.
I have an NSCell subclass that I do all kinds of custom drawing in. The only time things seem to be entirely out of my control is when right clicking a cell to show the associated context menu. While showing it's context menu, the table (or cell - not sure which exactly is doing this) draws a focus rect. I would like to get rid of this, or at least find a way to draw my own version of it that better fits within my interface.
I have tried about 15 different methods that seem like they could give me control over this focus rect drawing itself (various first responder methods, various drawing methods, various highlight color methods, etc.), but I have yet to find something that changes anything about it.
Screenshot of the problem: http://twitpic.com/3zx2t
I am almost annoyed enough to class-dump AppKit and try to find whatever private method it's using to draw this annoying focus rect. Nothing else I do has any effect on it. Any help here would really save both my sanity and lots of future hair pulling.
Thanks so much!
Without completely overriding your table view's -drawRect: this is the only other way I know to get rid of the context menu highlight rect.
- (void)_drawContextMenuHighlightForIndexes:(NSIndexSet *)rowIndexes clipRect:(NSRect)rect {
return;
}
This is the method, used in Leopard at least, to draw the highlight around cells that will be activated upon by a context menu. It is unfortunately called directly by NSTableView's -drawRect: method and as far as I know there is no other way to signal your disinterest in having those highlights drawn.
Of course this is private API, it may stop working in Snow Leopard, or some other release. But at worst that means that somewhere along the way the context menu highlight may start up again in your programs on newer releases or some other functionality using this method may not work later. You have been warned.
On 10.5 and later, NSTableView allows you to bring up a contextual menu on any item in the table (that is, without having the side effect of changing the selection.)
It draws that 'focus rect' to indicate which item(s) are being acted on by the contextual menu.