I've got a NSView subclass "graphics" where some rects are drawn.
Now I want a public method to move/resize the rects. I tried to set a new origins, but that doesn't work for me.
rect.origin.x = anything;
Now how can I move the rects?
regards
You are drawing the rectangles in a method called "drawRect", which is run every time the NSView thinks it should need to redisplay itself.
Your problem is that you are setting the initial location of the rectangles in this method, so every changed you make in other method wouldn't matter and would be reset every time. You should instead set the rectangles initial location in methods like init or awakeFromNib that only happen once.
After your button changed the values of the origin of the rectangle, you can tell the view to redraw itself, using :
[self setNeedsDisplay:YES];
So add this after the code that changes the rect origin and you should be fine.
Related
I am working on a small application on Mac that I need to create customed cursor and move it. I used NSImageView to implement it. However when I call setFrameOrigin (the same to setFrame) it will leaves images on the previous place.
Here is my code:
#property (nonatomic, strong) NSImageView *eraserView;
this is the define
_eraserView = [[NSImageView alloc] initWithFrame:CGRectMake(100, 100, 32, 32)];
_eraserView.image = [NSImage imageNamed:#"EraserCursor"];
[self.view addSubview:_eraserView];
[_eraserView setHidden:YES];
here is the initialization. Everything goes well until now but:
- (void)setImageatPoint:(NSPoint)point
{
[_eraserView setFrameOrigin:point];
}
- (void)hidePenImage
{
[_eraserView setHidden:YES];
}
- (void)unhidePenImage: (BOOL)isEraser
{
[_eraserView setHidden:NO];
}
These are methods I use to change the state of the NSImageView. They will be called by another class using delegate when corresponding events of trackpad occurs.
However every time I change the state of the NSImageView, it seems like it is drawn on the superview.
I debugged it and found there was no extra subviews. And when I use setHidden it has no effect on those tracks. I think it somehow did something to the CALayer, but I have no idea how to fix it.
Screenshots would help but in general if you move a view or change the area of the view that is drawn, you need to redraw.
To do this it kind of depends on how your drawing happens. Calling setNeedsDisplay may not be enough if your implementation of drawRect only draws a sub rect of the view bounds. Cocoa only draws what it is told to draw.
You can erase sections of the view that should be empty by drawing (filling) where it should be empty. That means drawing a color ( NSColor clearColor if nothing else) in the area that was previously drawn.
I'm working on an iPad app that lets you control different things in a prototype of an intelligent house. For example it lets you turn lights on and off. For this, I have made a UIImageView that shows the floor plan of the house and added UIButtons as subviews for each lamp that can be toggled.
As you can see the buttons are placed perfectly on the floor plan using the setFrame method of each UIButton. However, when I rotate the iPad to portrait orientation, the following happens:
The buttons obviously still have the same origin, however it is not relative to the repositioning of the image.
The floor plan image has the following settings for struts and springs:
and has its content mode set to Aspect Fit.
My question is
how do I dynamically reposition each UIButton, such that it has the same relative position. I figure I have to handle this in the {did/should}AutorotateToInterfaceOrientation delegate method.
It should be noted that the UIImageView is zoomable and to handle this I have implemented the scrollViewDidZoom delegate method as follows:
for (UIView *button in _floorPlanImage.subviews) {
CGRect oldFrame = button.frame;
[button.layer setAnchorPoint:CGPointMake(0.5, 1)];
button.frame = oldFrame;
button.transform = CGAffineTransformMakeScale(1.0/scrollView.zoomScale, 1.0/scrollView.zoomScale);
}
Thank you in advance!
I find the best way to layout subviews is in the - (void) layoutSubviews method. You will have to subclass your UIImageView and override the method.
This method will automatically get called whenever your frame changes and also gets called the first time your view gets presented.
If you put all your layout code in this method, it prevents layout fragmentation and repetition, keeps your view code in your views, and most things just work by default.
I have a UIView that contains another UIView. The outer UIView draws a border around the inner UIView via drawRect. (The border is too complicated to be drawn via CALayer properties.)
At present, when I animate the resizing of the outer UIView, its drawRect method is called once at the beginning of the animation and the result is stretched or shrunk. This does not look good.
I am looking for a way to either redraw the content at every step of the animation, or find a way to achieve the same visual effect. (The result should be similar to the resizing of a stretchable UIImage.)
You should change view's content type to:
your_view.contentMode = UIViewContentModeRedraw;
And it will redraw each time its frame changes.
I ended up adding subviews with autoresizing masks that kept them positioned correctly during the animation.
You need to send a [UIView setNeedsToDisplay] to the view for every time the frame size is changed, you could try overriding the setFrame: method like
- (void)setFrame:(CGRect)r
{
[super setFrame:r];
[self setNeedsToDisplay];
}
I have used the (void)drawRect:(NSRect)dirtyRect to draw triangles, which is displayed in a NSWindow. My triangles are drawn, but the problem is removing them from the window. I have to figure out how to remove/clear the lines that are drawn from the strokeLineFromPoint:toPoint using a simple method.
Thanks in advance!
You have to create a view and set it to the view property of the NSWindow. Then, draw using the view's drawRect method. The NSWindow does not have a drawRect method. Also, If you want to change the drawing, you have to redraw the part or the entire view.
You need to use the setNeedsDisplay method to redraw the view. So, you'd need something like this:
-(void) deleteStuff{
removeTriangles = YES; //Boolean value
[myView setNeedsDisplay];
}
Then, inside the drawRect function, simply put all your drawing code inside an if statement.
(void)drawRect:(NSRect)dirtyRect{
if(!removeTriangles){
//Rest of drawing code
}
}
Don't forget to set removeTriangles to NO originally so you can draw the triangles!
Hope this helps.
I have a CGContext, which I can turn into an NSGraphicsContext.
I have an NSWindow with a clipRect for the context.
I want to put a scrollview into the context and then some other view into the scrollview so I can put an image into it... However, I can't figure out how to attach the scrollview into the context.
Eventually the view will probably be coming from a nib, but I don't see how that would matter.
I've seen this thread, (http://lists.apple.com/archives/quartz-dev/2006/Nov/msg00010.html) But they seem to leave off the step of how to attach the view into the context, unless there's something obvious I'm missing.
EDIT:
The reason I'm in this situation is that I'm writing a Mozilla Plugin. The browser gives me a CGContext (Quartz) and a WindowRef (QuickDraw). I can turn the CGContext into an NSGraphicsContext, and I can turn the windowRef into an NSWindow. From another data structure I also have the clipping rectangle...
I'm trying to draw an image into that context, with scrollbars as needed, and buttons and other UI elements... so I need (want) an NSView...
You can't put a view into a graphics context. A view goes either into another view, or as the content view of a window.
You can draw a view into a context by setting that context as the current context and telling the view to draw. You might do this as a means of rendering the view to an image, but otherwise, I can't think of a reason to do it. (Edit: OK, being a Netscape plug-in is probably a good reason.)
Normally, a view gets its own graphics context in NSView's implementation of the lockFocus method, which is called for you by display, which is called for you by displayIfNeeded (only if the view needs display, obviously), which is called for you as part of the event loop.
You don't need to create a context for a view except in very rare circumstances, such as the export-to-an-image case I mentioned. Normally, you let the view take care of that itself.
A partial solution?
What I have done currently is create a nib with a button in an IKImageView inside an NSScrollView. I load this in my plugin.
Then, since I have the NSWindow, I can get the contentView of the window. Then, I add the scrollview as subview of contentView.
It appears, but there seems to be some coordinate confusion about where the origin is. (top vs bottom) and since I'm mucking with the contentview of the WHOLE WINDOW, I'm doing some stuff very globally that perhaps I should be doing more locally. Like, the view never disappears, even when you close the tab, or go to another tab. (it does close when you close the window of course)
So, does this sound like a reasonable way of doing this? it feels a bit ... kludgy...
For future generations (and me when I forget how I did this and Google leads me back to my own question) Here's how I'm doing this:
I have a NIB with all my views, I load this on start-up.
on SetWindow, I set the clip rect and actually do the attaching:
NP_CGContext* npContext = (NP_CGContext*) window->window;
NSWindow* browserWindow = [[[NSWindow alloc] initWithWindowRef:npContext->window] autorelease];
NSView* cView = [browserWindow contentView];
NSView* hitView = [cView hitTest:NSMakePoint(window->x + 1, clip.origin.y + 1)];
if (hitView == nil || ![[hitView className] isEqualToString:#"ChildView"])
{
return;
}
superView = [hitView retain];
[superView addSubview: topView];
[superView setNextResponder: topView];
[topView setNextResponder: nil];
[browserWindow makeFirstResponder: topView];
To make sure I only addSubView once, I have a flag...
And then in handleEvent, I actually draw, Because I'm using an IKImageView, I can use the undocumented method: [imageView setImage: image]; which takes an NSImage.
So far this seems to be working for me. Hopefully this helps someone else.