Cocoa editing NSBezierPath - objective-c

I have a simple bezierPath with 2 elements in a NSView;
I want to modify the last element (NSPoint) on a button pressed but my code don't have any visual effect on the path.
Here my code in NSView subclass:
NSBezierPath *path;
- (void)drawRect:(NSRect)dirtyRect {
[super drawRect:dirtyRect];
// Drawing code here.
path = [NSBezierPath bezierPath];
[path moveToPoint:NSMakePoint(0, 0)];
[path lineToPoint:NSMakePoint(60, 60)];
[path setLineWith:2.0];
[[NSColor redColor] set];
[path stroke];
//the path is correctly drawing and visible
}
- (IBAction)buttonPressed:(id)sender {
NSPoint newPoint = NSMakePoint(120, 120);
[path setAssociatedPoints:&newPoint atIndex:1]; //has no visible effect
}
any suggestion ?

Every time you call drawRect: you are creating a new path and drawing it. Then, on the button press you modify the path.
So you have 2 problems:
You keep recreating the path - just create it once when the view is created
You don't redraw the view when the path is updated - use setNeedsDisplay

You are recreating the Bezier path each time through your -drawRect: method. So, it doesn't matter that you kept the last one and modified it. You are discarding that and creating a new one the next time your view draws.
Also, if your variable is really just declared outside of any curly braces ({ … }), then it's not an instance variable. It's just a file-scope global variable. That means it's shared by all instances of this view class.

Related

NSComboBox - problems with background when selected

I'm a iOS developer, and recently I'm programming a desktop APP for MAC OSX. I still don't have much experience with the View's components of OSX, so maybe it's a silly or easy question, but I have made a little research about this problem and haven't found any solution yet.
Here's the problem:
I have a custom specialization of a NSView, that is used as the view of a Content ViewController used in my NSPopover.
Inside this view, that I'm calling "PopoverBackgroundView", I painted inside the drawRect this red background, and calculated another minor rect and painted with this gray-like color. Here's the code:
- (void)drawRect:(NSRect)dirtyRect
{
[[NSColor colorWithDeviceRed:174/255.0 green:72/255.0 blue:72/255.0 alpha:1.0] setFill];
NSRectFill(dirtyRect);
[[NSColor colorWithDeviceRed:51/255.0 green:51/255.0 blue:51/255.0 alpha:1.0] setFill];
NSRectFill(NSMakeRect(BORDER_WIDTH, BORDER_WIDTH, dirtyRect.size.width - 2*BORDER_WIDTH, dirtyRect.size.height - 2*BORDER_WIDTH));
}
So, inside the PopoverBackgroundView.m I'm programatically creating a NSComboBox. This comboBox will have the numbers 1 to 10. When I allocate it, everything seems just fine:
The problem is, after I select any options inside the combobox, it's background somehow "goes away" became transparent, I don't know, and become like this:
Please notice the red-like frame (background color of the view) around the NSComboBox, that appeared just AFTER I select something.
Here's the code where I'm allocation the comboBox and initializing it:
- (id)initWithFrame:(NSRect)frame
{
self = [super initWithFrame:frame];
if (self) {
(...)
self.comboBox = [[NSComboBox alloc] initWithFrame:CGRectMake(15, frame.size.height - 55, 90, 25)];
self.comboBox.delegate = self;
[self.comboBox setDrawsBackground:NO];
[self.comboBox setSelectable:YES];
[self.comboBox setEditable:NO];
for (int i = 1; i<=10; i++)
{
NSString *mystr = [NSString stringWithFormat:#"%d", i];
[self.comboBox addItemWithObjectValue:mystr];
}
[self addSubview:self.comboBox];
}
return self;
}
Any idea how can I 'fix' this "selected background"? All that I want it's the selected state to be equals to the normal state, i. e. ,the comboBox should be always like the first image, even after the selection.
Is there something wrong with the allocation code? Something mission? I'm really thinking that just some property that I'm not using or initializing, but I couldn't find yet.
Thanks in advance,
Just to give a feedback, I finally was able to resolve my problem.
I don't know exactly why, but the problem was all caused because the way I was drawing my border in the drawRect. Somehow, these code
[[NSColor colorWithDeviceRed:174/255.0 green:72/255.0 blue:72/255.0 alpha:1.0] setFill];
NSRectFill(dirtyRect);
were been propagated by the subviews, don't know if was the setFill or the NSRectFill. So, the "background" of the NSCombobox was been painted with this color.
After seeing this post :Adding border and Rounded Rect in the NSView I changed my draw rect to this:
- (void)drawRect:(NSRect)dirtyRect
{
NSBezierPath *background = [NSBezierPath bezierPathWithRoundedRect:self.bounds xRadius:10 yRadius:10];
[[NSColor colorWithDeviceRed:174/255.0 green:72/255.0 blue:72/255.0 alpha:1.0] set];
[background setLineWidth:10];
[background stroke];
}
and everything is working fine now, as I wanted. Now, after I select my combobox, no strange background is been drawing.
If someone knows whey this was happening with the previous code, please, let me know.

Rounded NSView in a Transparent Window

I'm trying to make a transparent NSWindow with a rounded view in there.
I'm trying to have a rounded view with a transparent window.
This is what it looks like now: (see the little dots in the corners)
Here's another example with the border radius set to 10px (set in NSView drawRect):
I am using code from this Apple sample: https://developer.apple.com/library/mac/#samplecode/RoundTransparentWindow/Introduction/Intro.html
Specifically this method in my NSWindow subclass:
- (id)initWithContentRect:(NSRect)contentRect
styleMask:(NSUInteger)aStyle
backing:(NSBackingStoreType)bufferingType
defer:(BOOL)flag {
// Using NSBorderlessWindowMask results in a window without a title bar.
self = [super initWithContentRect:contentRect styleMask:NSBorderlessWindowMask backing:NSBackingStoreBuffered defer:NO];
if (self != nil) {
// Start with no transparency for all drawing into the window
[self setAlphaValue:1.0];
// Turn off opacity so that the parts of the window that are not drawn into are transparent.
[self setOpaque:NO];
[self setBackgroundColor:[NSColor clearColor]];
}
return self;
}
And this in my NSView subclass:
- (void)drawRect:(NSRect)dirtyRect
{
[[NSColor redColor] set];
NSBezierPath* thePath = [NSBezierPath bezierPath];
[thePath appendBezierPathWithRoundedRect:dirtyRect xRadius:3 yRadius:3];
[thePath fill];
}
Can anyone tell me what I'm missing here?
Thanks.
Are you looking for something like the following, where there's a red outline (stroke), but the center area is transparent?
If so, to achieve that, I used the following code:
- (void)drawRect:(NSRect)frame {
frame = NSInsetRect(self.frame, 3.0, 3.0);
[NSBezierPath setDefaultLineWidth:6.0];
NSBezierPath *path = [NSBezierPath bezierPathWithRoundedRect:frame
xRadius:6.0 yRadius:6.0];
[[NSColor redColor] set];
[path stroke];
}
If that's what you're looking for, you can probably use that as a starting point. You'll want to make sure that you inset the frame rect one half of the stroke line width, so as to avoid the problem with clipping the corners like you were seeing.
Not sure if this is what you are looking for but there is a great class by Matt Gemmell called MAAttachedWindow and can be found here: http://mattgemmell.com/2007/10/03/maattachedwindow-nswindow-subclass/
It's a little older but still works great for me when I need to do a 'floating' popup window and configure transparency, border radii, and even add a small arrow for context if desired. I use it all the time.

How to deal with drawRect in cocoa?

I have to draw lines few times. I do this now:
- (void)drawRect:(NSRect)dirtyRect
{
[NSGraphicsContext saveGraphicsState];
NSBezierPath *path = [NSBezierPath bezierPath];
[path moveToPoint:point];
[[NSColor blackColor] set];
[path lineToPoint:point2];
[path stroke];
[NSGraphicsContext restoreGraphicsState];
}
And i call this from other class many time with other parameters:
[workspace setPoint1:someValue setPoint2:someOtherValue];
[workspace setNeedsDisplay:YES];
What i need?
I call this few times with changing parameters someValue and someOtherValue and I have to draw all lines and I want to see it. Now i see only last path. Where is the problem? How can i do this correctly?
Thank you.
If you want to draw more than one line, you'll need to... well... draw more than one line.
You'll need to come up with some way of storing all of the line segments that you want to draw, not just the most recent one. (Use NSMutableArray for this.) Once you've got that, you'll need to loop through that array and draw each line.

being called but not drawing

I have some code in the drawRect: method that draws a series of circles from an array. I can verify that the points stay in memory long enough and get to the point where they should be drawn. However, it seems as if the fill method of NSBezierPath is not drawing the circles.
Here is my drawRect:
- (void)drawRect:(NSRect)dirtyRect
{
NSPoint aPoint;
NSRect aRect = NSMakeRect(0, 0, 6, 6);
// Erase the rectangle
[[NSColor clearColor] set];
NSRectFill([self bounds]);
// Draw the dots
[[NSColor colorWithCalibratedRed:(77.0/255.0) green:(11.0/255.0) blue:(11.0/255.0) alpha:1.0] set];
for(NSValue *aValuePoint in arrayOfPoints) {
aPoint = [aValuePoint pointValue];
aRect.origin.y = aPoint.y - aRect.size.height/2.0;
aRect.origin.x = aPoint.x - aRect.size.width/2.0;
// The code does get to this point, it does not draw however...
[[NSBezierPath bezierPathWithOvalInRect:aRect] fill];
}
}
I have another method drawDotAtPoint: where I add the points to an array
- (void)drawDotAtPoint:(NSPoint)aPoint
{
NSLog(#"drawDotAtPoint:(%f, %f)", aPoint.x, aPoint.y);
[arrayOfPoints addObject:[NSValue valueWithPoint:aPoint]];
// I've also tried using [self superview] instead of just self
[self setNeedsDisplay: YES];
}
And while I am able to verify that these methods are called at the correct times (or so it seems) no drawing after the initial drawRect: will take place
Sidenote:
My goal is to actually draw a point and have a ring appear around it, enlarge and fade out. Much similar to the GPS current location indicator on iOS, in the Maps app. Any insight on that would also be appreciated.
Check your points and make sure that you don't have an inverted rectangle and that your X/Y coords are what you expect. Make sure that your anchor point and coordinates are correctly relative.
You may be helped along a bit by using a tool called Quartz Debug that comes with apple's developer tools. It is in the /Developer/Applications/Graphics Tools/ folder. After starting this tool, go to the "tools" menu and turn on "Flash Screen Updates". This will give you an idea of when things are being redrawn or not.
Hope that helps some.
I've copy-pasted your view code. I stuck this in an app delegate for testing. BadView is the custom view here (no reflection on you -- "Bad" because it's misbehaving :) ) The windows are both created in IB, and the WebView is likewise placed in the parent window in IB.
- (void)applicationDidFinishLaunching:(NSNotification *)aNotification {
// badWindow is an IBOutlet to the overlay window, parentWindow an IBOutlet
// to the window with the webview, myWebView an IBOutlet to the webview
BadView * myBadView = [[BadView alloc] initWithFrame:[[badWindow contentView] frame]];
// Create some random points for testing
[myBadView createArrayOfPoints];
[badWindow setStyleMask:NSBorderlessWindowMask];
[badWindow setOpaque:NO];
[badWindow setAlphaValue:0.9]; // Will still act opaque without this
[badWindow setHasShadow:NO];
[badWindow setContentView:myBadView];
[parentWindow addChildWindow:badWindow ordered:NSWindowAbove];
[[myWebView mainFrame] loadRequest:[NSURLRequest requestWithURL:
[NSURL URLWithString:#"http://www.apple.com/"]]];
[myBadView release];
}

Overlay NSScroller over content

Is there any way to overlay the NSScroller over the content of the scroll view (like in iOS)? I've already tried several approaches:
a) setting the frame of the scroll view content view (NSClipView) to extend into the bounds of the scroller
b) adding an NSScroller object as a subview of the scroll view (positioned where I want)
c) creating an entirely custom scroller view and placing it as a subview (this worked, but that would mean that I need to rewrite all the functionality of NSScroller)
Sparrow seems to successfully do this, and it seems to do it through a regular NSScroller subclass (seeing as it responds to the scroll settings set in System Preferences >> Appearance). It's not really drawing the scroller that's the issue, its just making it overlay the content.
Any advice is appreciated :-)
Here's where you can set the custom class of your scrollbars.
After that, by overriding the -tile method of NSScrollView, you'll get them placed properly.
Here is my solution :
Create a MyScroller class that extends NSScroller
In the MyScroller.m :
#import "MyScroller.h"
#implementation MyScroller
+(CGFloat) scrollerWidth{
return 10;
}
+(CGFloat) scrollerWidthForControlSize:(NSControlSize)controlSize{
return 10;
}
- (void) drawBackground:(NSRect) rect{
NSBezierPath *path = [NSBezierPath bezierPathWithRoundedRect:rect xRadius:0 yRadius:0];
[[NSColor whiteColor] set];
[path fill];
}
- (void)drawKnob{
[self drawBackground:[self rectForPart:0]];
[self drawBackground:[self rectForPart:1]];
[self drawBackground:[self rectForPart:2]];
[self drawBackground:[self rectForPart:4]];
[self drawBackground:[self rectForPart:5]];
[self drawBackground:[self rectForPart:6]];
NSRect knobRect = [self rectForPart:NSScrollerKnob];
NSRect newRect = NSMakeRect((knobRect.size.width - [MyScroller scrollerWidth]) / 2, knobRect.origin.y, [MyScroller scrollerWidth], knobRect.size.height);
NSBezierPath *path = [NSBezierPath bezierPathWithRoundedRect:newRect xRadius:5 yRadius:5];
[[NSColor grayColor] set];
[path fill];
}
#end
Then just set the custom class for the Scroller in Interface Builder.
I've recently released RFOverlayScrollView which should solve your problem:
Source: https://github.com/rheinfabrik/RFOverlayScrollView
Blog Post: http://blog.rheinfabrik.de/blog/2013/01/01/introducing-rfoverlayscrollview/
You can change the scrollerStyle over the NSScrollerView control to .overlay to get the desired overlay effect.
This may overrule the system wide setting in System Settings for scroll bar visibility. To 'survive' scroll bar setting changes while your app is running, you must observe the NSScroller.preferredScrollerStyleDidChangeNotification and re-apply the overlay effect.