I have a game in which i have some sprites using physical body and it has a stroke around a physical body. How to hide it?!
Somewhere in your code, you might have set
self.view.showsPhysics = YES; //Within the scene
or
skview.showsPhysics = YES; //from the viewcontroller
The showsPhysics method tells the SKView to actually draw the physicsBodies on top of the nodes they are associated with. A description of the method is given in the documentation.
Either remove the above lines or set the showsPhysics property to NO in order to solve this problem.
Related
Here's my drawRect code:
- (void)drawRect:(CGRect)rect {
if (currentLayer) {
[currentLayer removeFromSuperlayer];
}
if (currentPath) {
currentLayer = [[CAShapeLayer alloc] init];
currentLayer.frame = self.bounds;
currentLayer.path = currentPath.CGPath;
if ([SettingsManager shared].isColorInverted) {
currentLayer.strokeColor = [UIColor blackColor].CGColor;
} else {
currentLayer.strokeColor = [UIColor whiteColor].CGColor;
}
currentLayer.strokeColor = _strokeColorX.CGColor;
currentLayer.fillColor = [UIColor clearColor].CGColor;
currentLayer.lineWidth = self.test;
currentLayer.contentsGravity = kCAGravityCenter;
[self.layer addSublayer:currentLayer];
//currentLayer.position = CGPointMake(CGRectGetMidX(self.frame), CGRectGetMidY(self.frame));
}
//[currentPath stroke];
}
"The portion of the view’s bounds that needs to be updated"
That's from the apple dev docs.
I am dealing with a UIView and a device called a slate -the slate has the ability to record pencil drawings to my iOS app. I managed to get it working on the entire view. But, I dont want the entire view to be filled with the slate input. Instead, I'd like to modify the UIView to have a height of phonesize - 40px; Makes sense?
I found out if I set the frame that I have as currentLayer to new bounds the screen that can be drawn on is resized accordingly.
I think you’re mixing up the meaning of the various rectangles in UIView. The drawRect parameter designates a partial section of the view that needs to be redrawn. This can be that you called setNeedsDisplay(rect), or this can be because iOS thinks it needs to be redrawn (e.g. because your app‘s drawings were ignored because the screen was locked, and now the user unlocked the screen and current drawings are needed).
This rectangle has nothing to do with the size at which your contents are drawn. The size of the area your view is drawn in is controlled by its frame and bounds, the former of which is usually controlled using Auto Layout (i.e. layout constraint objects).
In general, while in drawRect, you look at the bounds of your view to get the full rectangle to draw in. The parameter to drawRect, on the other hand, is there to allow you to optimize your drawing to only redraw the parts that actually changed.
Also, it is in general a bad idea to manipulate the view and layer hierarchies from inside drawRect. The UIView drawing mechanism expects you to only draw your current view‘s state in there. Since it recursively walks the list of views and subviews to call drawRect, you changing the list of views or layers can cause weird side effects like views being skipped until the next redraw.
Create and add new layers in your state-changing methods or event handling methods, and position them using auto layout or from inside layoutSubviews.
I'm creating a NSCell subclass that draws some objects directly onto the view (using drawInRect:fromRect:operation:fraction:respectFlipped:hints:) and also draws an NSButton instance simply using NSView's addSubview: selector.
While objects drawn using the first method all draw correclty, I'm having problems with drawing the NSButton correctly. The issue is that my NSButton instances will draw in the right places, but multiple times over.
I've researched this on the internet for a while and some people suggested using a cache, but I'm not sure if this is efficient. (going an array containing buttons using a for loop will definately cause slow scrolling since I display a lot of data...)
How would you do this? Am I barking up the wrong tree?
This is the relevant code:
- (void)drawInteriorWithFrame:(NSRect)cellFrame inView:(NSView *)controlView
{
NSRect _controlRect = cellFrame;
float _Y = cellFrame.origin.y;
NSRect _accessoryRect = NSMakeRect(_controlRect.size.width - 70.0f, _Y + 9.0f, 50.0f, 23.0f);
_switch = [self _choiceSwitch];
[_switch setFrame:_accessoryRect];
[controlView addSubview:_switch];
}
Long story short: Friends don't let friends addSubview, while drawing.
This a fundamental, and not particularly well-explained aspect of managing control interfaces, but is important to come to grips with.
Let your controllers dictate the "order" of subviews, and you can sleep tight knowing that that button shouldn't get overtly mucked about (which is NOT the case if it's getting jostled around inside your custom drawing routines).
It's easy to get trapped in this alley, cause, like, hey, I added an NSImageView in my initWithFrame and everything seems to be okay… But it's just sort of not how you're supposed to do it, I guess… and when you start subclassing NSControl, etc. is when you start to realize why.
Updated: Here's a really good write up on designing custom controls with an equally as great sample project attached - which embodies the kind of code organization that can help avoid this type of issue. For example.. you'll notice in the controller class how he's keeping each button seperate, unique, and independent of other views' business…
for (int butts = 0; butts < 3; butts++) {
NSRect buttFrame = NSMakeRect(0, butts * 10, 69, 10);
ExampleButt *butt = [[ExampleButt alloc]initWithFrame:buttFrame];
[mainView addSubview:butt];
}
“Drawing” NSButton by adding its instance into the view hierarchy each time you draw the cell itself is definitely a bad idea. Instead, create an NSButtonCell and configure it up to your taste. Then, in your -[NSCell drawInteriorWithFrame:inView:] use a cell ivar to draw its appearance.
If you want to have a clickable NSButton instance in each cell of the table view, try to avoid a call to addSubview: when possible. Each time you do this, the control view may invalidate its layout and re-draw everything from scratch making some kind of a recursion in your case.
Part of my iPad app allows users to draw paths to connect different parts of the screen. They all have the same color (white) and line width. Each path is represented as a UIBezierPath. Besides their locations, they look identical. Since users are only editing one path at a time, I want to make it so that they can visually see which path they are editing.
Is there a way to animate the path, so that the user has a visual queue about which path they are editing? I'm thinking that maybe the current path could glow or have moving dotted lines. I don't want to change the base color, since I use many colors in the other parts of application (pretty much all major colors except white).
I haven't done this in an animated way, but I make my currently drawing paths have dashed lines, and then solid once the drawing ends. I subclassed NSBezierPath, and added a selected property. The setSelected method looks like this:
-(void)setSelected:(BOOL) yes_no {
selected = yes_no;
if (yes_no == YES) {
CGFloat dashArray[2];
dashArray[0] = 5;
dashArray[1] = 2;
[self setLineDash:dashArray count:2 phase:0];
self.pathColor = [self.unselectedColor highlightWithLevel:.5];
} else {
[self setLineDash:nil count:2 phase:0];
self.pathColor = self.unselectedColor;
}
}
I set the property to YES in the mouseDragged: method, and then to NO in mouseUP:
I have a UITableView that I build in loadView. One of the things I do in loadView is create a UIView to act as the table header and stuff a UIImageView into it. The image view contains an image that is a stylized title, so I want to add an accessibility label for VoiceOver users. However, I can't get VoiceOver to "focus" on the image in order to read the label, and the Accessibility Inspector doesn't respond to clicking on the image in the simulator. My (abbreviated) code follows:
... in -loadView ...
// Make header view
UIView *headerView = [[UIView alloc] initWithFrame:CGRectMake(...)];
UIImageView *titleImageView = [[UIImageView alloc] initWithImage:[self titleImage]];
titleImageView.accessibilityLabel = [self accessibilityLabelForTitleImage];
[headerView addSubview:titleImageView];
// Make table view
self.tableView = [[UITableView alloc] initWithFrame:CGRect(...) style:UITableViewStylePlain];
self.tableView.tableHeaderView = headerView;
... code continues ...
I've stepped through in gdb and accessibilityLabelForTitleImage returns a string. po [titleImageView accessibilityLabel] prints out the correct string, but I'm still unable to focus on the image view. Note that the views themselves appear and respond as appropriate.
Am I missing something? Is there a way to force VoiceOver to acknowledge an image view?
In Voice-Over , in order to make an element accessible :-
you have to set setIsAccessibilityElement property as true which i don't find in your code.
The other important point is that to make child elements (subviews) to be accessible , you have to seperately make them accessible while the parent should not be accessible(you have to specify this also).
Implement the UIAccessibilityContainer Protocol in your custom - cell.
It will be a big story if i go on .Please refer this Accessibility voice over by apple.
Hope this helps.
I used KIF for testing my IOS app. In my tableview, I assigned value to tableview.accesssibilityIdentifier instead of tableview.accessibilityLabel. It worked for me. Wanna give it a try?
Voice-Over sometimes can get nasty and just by setting isAccessibilityElement might not work.
In this case try setting accessibilityElements on the parent view and include the child views in the array, like this:
parentView.accessibilityElements = [childView1, childView1, childView1]
Doing it also ensures that the accessibility items are being read in the order you want.
I'm working on some drawing code. I have that portion working great.
I want to draw over an image, but I want to still be able to see the detail of the image, the black lines, etc.
What I am working on is making a transparent UIImageView that holds the image.
I'm not sure how to get this set up properly though.
Should this be added above the other UIImageView that I color on or below it?
Here's what I have so far:
- (void)viewDidLoad
{
[super viewDidLoad];
topImageView = [[UIImageView alloc] initWithFrame:CGRectMake(0, 46, 320, 370)];
[topImageView setImage:[UIImage imageNamed:#"imagesmall.png"]];
topImageView.alpha = 1.0;
topImageView.layer.opacity = 1.0;
topImageView.layer.opaque = NO;
[self.view addSubview:topImageView];
[topImageView release];
}
Thoughts anyone?
Yes, you can draw views over other views. They are drawn in the order that they're added as subviews, unless you reorder them after that.
You may need to set the opaque property for some views (this is distinct from and overrides their layer opacity), and set their backgroundColor to nil. UIImageView seems to be transparent by default, as long as its image is; some other UIView subclasses are not.
So, just what is your overlay going to be? If you just need to display one image over another, what you have here seems to work already. If you need to draw some lines programmatically, you'll need to do this:
Create a subclass of UIView.
Implement its drawRect method to display the content you need.
When you add your custom view on top of the background image, make sure it is not opaque and has no backgroundColor.
A common problem here is to find that your foreground is working, but the background isn't being loaded properly. To make sure the background is there, set the alpha of the foreground view to 0.5. You won't want to do that in production, but it will allow you to verify that both views exist.