Im using Xcode to make an application that has a NSImageView that I have made into an NSScrollView (I think) by means of selecting it in my .xib, going to the editor menu in Xcode then embedded in > scrollView.
I have an image in my NSScrollView that is larger than the window it is opened in, I can scroll using the scroll bars fine and have even turned on the autoscroll: function in my mouseDragged: method.
I would like to be able to simply pan around the image without touching the edges of the screen using mouseDragged:. So far my code for mouseDragged: in my panning.m(subclass of NSImageView) is such:
-(void)mouseDragged:(NSEvent *)theEvent{
NSPoint p = [theEvent locationInWindow];
[self scrollRectToVisible:NSMakeRect(p.x - self.visibleRect.origin.x, p.y - self.visibleRect.origin.y, self.visibleRect.size.width, self.visibleRect.size.height)];
[self autoscroll:theEvent];
}
This works to some degree, however there is a lot of jittering. Maybe because I am not restricting the bounds?
I was wondering if I am on the right track or is there a better/more efficient way.
Any help is appreciated.
Cheers.
Related
I have an NSScrollView with a custom NSImageView as its document view set up in the xib file. My problem comes when I want to magnify the NSScrollView. I would like it to behave like the Preview app on Mac, and I can get it to magnify just fine, but I want it to magnify with the cursor as the centered point.
I have this code in my custom NSScrollView class:
//Informs the receiver that the user has begun a pinch gesture.
- (void)magnifyWithEvent:(NSEvent *)event {
NSPoint conViewPoint =[[self contentView] convertPoint:[event locationInWindow] fromView:nil];
[self setMagnification:[event magnification]+[self magnification] centeredAtPoint:conViewPoint];
}
This works, however it also causes the scroll view to scroll down as it magnifies (though it doesn't move sideways at all). It's more noticeable when zooming in and out multiple times without lifting from the trackpad.
A similar problem seems to be in this question, however I'm using a pinch gesture and not buttons. I've been trying to offset the y axis scrolling as suggested for that question with
[[self documentView] scrollPoint:scrollPoint]
but I haven't been able to figure out a working formula for scrollPoint that accounts for the changing content view bounds to keep the point under the cursor in the same place. So, I'm wondering if there is a more proper approach to this or if the scrolling really is needed and I just need to figure out the math.
Thanks for any help with this
EDIT:
So I finally figured out the scrolling math. It took a while and way more complicated attempts, but is pretty simple in the end:
- (void)magnifyWithEvent:(NSEvent *)event {
NSPoint docViewPoint =[[self documentView] convertPoint:[event locationInWindow] fromView:nil];
NSPoint docRectOri=[self documentVisibleRect].origin;
float widthGapSize=-docRectOri.x;
float heightGapSize=-docRectOri.y;
if([event phase]==NSEventPhaseBegan){
startDocPoint=docViewPoint;
startPoint.x=(docViewPoint.x+widthGapSize)*[self magnification];
startPoint.y=(docViewPoint.y+heightGapSize)*[self magnification];
}
scrollPoint.x=startDocPoint.x-(startPoint.x/[self magnification]);
scrollPoint.y=startDocPoint.y-(startPoint.y/[self magnification]);
[self setMagnification:[event magnification]+[self magnification] centeredAtPoint:docViewPoint];
[[self documentView] scrollPoint:scrollPoint];
}
I still don't understand why setMagnification:centeredAtPoint: doesn't just work and am still wondering if anyone has some input on this as my workaround is very jittery on magnification because of the scrolling.
This is for a Mac app written with Cocoa and Objective-C.
I have a custom NSView class that essentially works as a collection of buttons and stores the value of the selected button. Sort of like an NSSlider that snaps to the tick marks but with buttons instead of a slider. The image below on the left is what it looks like.
Now what I want to do is make it so that when the mouse moves over each button, it covers that button with a semi-transparent blue color that then stays there when it is clicked. I've made a few attempts and you can see the latest result in the image on the right:
This is what happens after mousing over all the buttons. For some reason it draws using the window's origin instead of drawing inside the MyButtonView. Also, it is not semi-transparent. I haven't yet worried about redrawing the normal button when the mouse leaves the rectangle since this part isn't working yet anyway.
Now here's the pertinent code.
Inside the initWithFrame method of the MyButtonView class:
for (int i = 0; i < 12; i++) {
yOrigin = kBorderSize + (buttonHeight * i) + (kSeparatorSize * i);
NSRect newRect = { {xOrigin, yOrigin}, {buttonWidth, buttonHeight} };
[buttonRectangles addObject:NSStringFromRect(newRect)];
[self addTrackingRect:newRect owner:self userData:NULL assumeInside:NO];
}
The methods that draw the blue rectangles:
- (void)mouseEntered:(NSEvent *)theEvent {
NSRect rect = [[theEvent trackingArea] rect];
[self drawHoverRect:rect withColor:hoverBlue];
}
- (void)drawHoverRect:(NSRect)rect withColor:(NSColor *)color {
[color set];
NSRectFill(rect);
[self displayRect:rect];
}
I have no idea how to do this. I've been poring over Apple's documentation for a few hours and can't figure it out. Obviously though, I'm no veteran to Cocoa or Objective-C so I would love some help.
One fundamental problem you have is that you are bypassing the normal drawing mechanisms and trying to force the drawing yourself. This is a common mistake for first timers. Before you go any further, you should read Apple's View Programming Guide:
https://developer.apple.com/library/mac/documentation/Cocoa/Conceptual/CocoaViewsGuide/Introduction/Introduction.html#//apple_ref/doc/uid/TP40002978
If you have trouble with that, then you might need to back up and start with some of the more fundamental Objective-C/Cocoa guides and documentation.
Back to your actual view, one thing that you are going to have to do in this view is do all your drawing in the drawRect: method. You should be tracking the state of your mouse movements via some kind of data structure and then drawing according to that data structure in your drawRect: method. You will call
[self setNeedsDisplay:YES];
in your mouse tracking method(s), after you've recorded whatever change has occurred in your data structure. If you only want to ever draw one button highlighted at a time, then your data structure could be as simple as an NSInteger whose value you set to the index of your selected button (or -1 or whatever to indicate no selection).
For the sake of learning, the reason your blue boxes are currently drawing from the window's origin is that you are calling drawing code outside of the "context" that's normally setup for your view when drawRect: is called by the system. That "context" would include a translation to move the current origin to the origin of your view, rather than the origin of the window.
I'm new to XCode and am having trouble getting a subView, when added to the main view, to originate from the bottom whereas the top (which I presume is default).
When I mean top, I don't mean the heir-achy but rather literally top of the screen (where the power button and ear jack of an iphone is).
I have tried to play around with the View -> Origin, and View -> Mode - neither did anything.
I would assume it's the auto-layout but I can't be sure.
Basically, I have a colored mainStoryboard and it [self.view addSubView:[[AnotherView alloc] initWithNibName:#"AnotherView" bundle:nil]];
The AnotherView is just a empty half-sized View.
When it gets added, it keeps appearing from the top. I don't know how to make it come from the bottom.
Do you guys have any insight as to how I might be able to make it come from the bottom?
Thanks ahead of time!
add newView to self.view with the frame
newView.frame=CGRectMake(0,480,320,200);
and after that animate that view by using below animations.
[UIView animateWithDuration:0.4 delay:0.0 options:UIViewAnimationTransitionCurlUp
animations:^{
newView.frame=CGRectMake(0,0,320,200);
} completion:nil];
Or you can use
presentModalViewController: animated:
method
I'm placing a few buttons in a simple rectangular NSview which acts as a custom toolbar. On first render the buttons/views come out as expected, but every time a button is pressed (and sometimes with no mouse interaction at all) artefacts start appearing.
Before
After
I can eliminate the artefacts by calling a [self.toolbarView setNeedsDisplay:YES] in all the action and focus methods but this seems like a hack, is there any clean way to deal with this?
It was a beginner's problem. In the drawRect method
- (void)drawRect:(NSRect)dirtyRect
I was using the param dirtyRect for drawing an outline of my view, assuming it was the view's bounds, where in fact it was only the area around the buttons that became dirty when they were pressed. The 'artefacts' were actually my outline being drawn in the wrong place.
By correctly using the bounds of the view
NSRect drawingRect = [self bounds];
the 'artefacts' no longer appeared.
You just try to set focus ring for a buttons to 'none' in IB.
The problem
I have a transparent NSView on a transparent NSWindow. The view's drawRect: method draws some content (NSImages, NSBezierPaths and NSStrings) on the view but leaves parts of it transparent.
Clicking on the regions of the view that have been drawn on invokes the usual mouse event handling methods (mouseDown: and mouseUp:).
Clicking on the transparent areas gives focus to whatever window is behind my transparent window.
I would like to make parts of the transparent region clickable so that accidentally clicking between the elements drawn on my view does not cause the window to lose focus.
Solutions already attempted
Overriding the NSView's hitTest: method. Found that hitTest: was only called when clicking on a non-transparent area of the view.
Overriding the NSView's opaqueAncestor method. Found that this was not called when clicking on any part of the view.
Filling portions of the transparent area with [NSColor clearColor] in the drawRect: method, and with an almost-but-not-quite-transparent colour. This had no effect.
Experimented with the NSTrackingArea class. This appears to only add support for mouseEntered:, mouseExited:, mouseMoved:, and cursorUpdate: methods, not mouseUp: and mouseDown:.
I had the same problem. It looks like [window setIgnoresMouseEvents:NO] will do it.
(On Lion, at least. See http://www.cocoabuilder.com/archive/cocoa/306910-lion-breaks-the-ability-to-click-through-transparent-window-areas-when-the-window-is-resizable.html)
As far as I know, click events to transparent portions of windows aren't delivered to your application at all, so none of the normal event-chain overrides (i.e -hitTest:, -sendEvent:, etc) will work. The only way I can think of off the top of my head is to use Quartz Event Taps to capture all mouse clicks and then figure out if they're over a transparent area of your window manually. That, frankly, sounds like a huge PITA for not much gain.
George : you mentioned that you tried filling portions with an almost but not quite transparent color. In my testing, it only seems to work if the alpha value is above 0.05, so you might have some luck with something like this:
[[NSColor colorWithCalibratedRed:0.01 green:0.01 blue:0.01 alpha:0.05] set];
It's an ugly kludge, but it might work well enough to avoid using an event tap.
Did you try overriding
- (NSView *)hitTest:(NSPoint)aPoint
in your NSView sublcass?
You can use an event monitor to catch events outside a window/view.
https://developer.apple.com/library/mac/documentation/cocoa/conceptual/eventoverview/MonitoringEvents/MonitoringEvents.html
You can override the hitTest method in your NSView so that it always returns itself.
According to the NSView documentation, the hitTest method will either return the NSView that the user has clicked on, or nil if the point is not inside the NSView. In this case, I would invoke [super hitTest:], and then return the current view only if the result would otherwise be nil (just in case your custom view contains subviews).
- (NSView *)hitTest:(NSPoint)aPoint
{
NSView * clickedView = [super hitTest:aPoint];
if (clickedView == nil)
{
clickedView = self;
}
return clickedView;
}
You can do:
NSView* windowContent = [window contentView];
[windowContent setWantsLayer:YES]
Making sure that the background is transparent:
[[windowContent layer] setBackgroundColor:[[NSColor clearColor] CGColor]];
Another option would be to add a transparent background image that fills the contentView.