I want a view like the picture attached, the full view's background is translucent, and the view in green frame is transparent.
I tried addSubview and set subview's alpha but it is not worked.
You can override your drawRect method. Fill it all with translucent, then fill in the transparent part with clear color:
- (void)drawRect:(CGRect)rect {
// fill it all with translucent
[yourTranslucentUIColor setFill];
UIRectFill( rect );
CGRect yourMiddleHoleRect = CGRectMake(* calculate your rect here);
[[UIColor clearColor] setFill];
UIRectFill( yourMiddleHoleRect );
}
I think this will give you a cleaner result than other options.
You could even draw in those green frame indicators here if you wanted.
I believe the only way to achieve that is to instead add 4 translucent views around your transparent view.
first you have to add the translucent view over the background view by CGContextDrawImage.
Then use CGContextSetBlendMode to clear the portion.
Refer the below project to achieve this.
https://github.com/akopanev/iOS-Scratch-n-See
Related
I'm currently working with transparency and I'd like to have the following effect:
As you can see the line takes the full width of the view. There are some transparent UIViews also on this screen. The line seems to be below the transparent UIView and if it overlaps it has another color, because of the transparent UIView above. When there is no overlapping the line get its normal color.
How can I get this effect?
I tried to set the background of the UIView to transparent, but it didn't helped. The line has its normal color and doesn't interact with the transparency. Furthermore I tried to change the transparency of the view itself but with the same wrong result.
The rectangle above is done with code
UIView rectangle = new UIView (new CGRect (10, 10, 200, 120));
rectangle.BackgroundColor = UIColor.FromRGBA (204,115,225, 50);
UIView line = new UIView (new CGRect (0, 105, 320, 1));
line.BackgroundColor = UIColor.Red;
View.AddSubview (line);
View.AddSubview (rectangle);
line.SendSubviewToBack (rectangle);
the rectangle below is created in iOS designer.
Am I missing something?
Its all about the z order of the Subviews.
line.SendSubviewToBack (rectangle);
is probably not what you want.
If you add the line with its normal red color and add a UIView that has its alpha dropped to e.g. 0.5, then you should get the effect you want.
The z-order of the subviews was correct in my case. Depending on the color the effect I want is possible or not. So I made the following:
Choose another background color for the lavender color rectangles and adapt the alpha transparency to look similar. So something like this:
rectangle.BackgroundColor = UIColor.FromRGBA (245/255.0f,227/255.0f,249/255.0f,0.7f);
Let me explain my situation first. I set the UINavigationBar color in my appDelegate Like:
[[UINavigationBar appearance] setBarTintColor:[UIColor colorWithRed:255.0f/255.0f green:87.0f/255.0f blue:10.0f/255.0f alpha:1]];
Now in my some viewController the translucent of UINavigationBar set as YES.
self.navigationController.navigationBar.translucent = YES;
That's why there is a shade over my UINavigationBar. It wasn't showing the exact color. As a solution, I set translucent from YES to NO. It is showing the exact color now, But I am facing that some of my view completely gone from my interface. Here, let me tell you one thing that, so many of views here, is positioned by programmatically, so I am afraid I can't just move every of my viewControllers view 64 px high. Just wondering is there any solution to solve the thing. I try with opaque, but no luck. If any one understand my problem please share the solution if you have. Thanks a lot in advance.
From iOS7 if you use a translucent bar ( in UINavigationController or UITabbarController) the hosted view controller has as default behavior to extend under them. If you say to set the bar as translucent the color of it it will be a combination of the view under it and bat color. That is normal and the only way is to set translucency to no or apply a background image to navigation bar.
Applying frames manually will lead to unexpected result under auto layout, you must use constraints.
[UPDATE]
To create a background image from a solid color you can use that method, the image is 1px square, but there is no problem because it can be stretched or tiled to cover the entire area:
+ (UIImage *) imageWithColor:(UIColor*) color {
CGRect rect = CGRectMake(0, 0, 1, 1);
UIGraphicsBeginImageContext(rect.size);
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSetFillColorWithColor(context, color.CGColor);
CGContextFillRect(context, rect);
UIImage *colorImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return colorImage;
}
If you see and extra gap is probably because you have also set automaticallyAdjustScrollViewInset to YES, try setting it NO. This property add and extra inset to your view or your vfirst view subview if it inherits from a UIScrollView
Its late, but i face same issue, and i resolved it by making UINavigationbar none on Viewcontroller in storyboard, and resized the view to start from 0,0
I am a new iOS developer, i found some apps that can have a totally transparent nav bar, but still float above all the content, such as the app has a very nice background picture, and the nav bar is transparent, so you can see the entire background, but there is a scroll view on the navigation view controller. when scroll, it still goes under the nav bar.
when i try it, i set up my nav bar background as transparent like this
[self.navigationController.navigationBar setBackgroundImage:[self imageWithColor:[UIColor clearColor]] forBarMetrics:UIBarMetricsDefault];
but my scroll view will be totally visible when it goes under nav bar. I don't like that, does any one know how to make the nav bar transparent but still kind of floating on everything?
Thank you guys for the reputations, here is a screen shot from Yahoo weather their nav bar does exactly what i want.
But when i set the clear background to it, it becomes like this.
I am not 100% sure how Yahoo did it, but i can kind of fake that effect like this
I am inspired by BTGlassScrollView (https://github.com/BTLibrary/BTGlassScrollView) the approach i am using have several steps:
1.> set up your navigation controller like this:
Put your background image view first
Then add a wrapper view for your scroll view, and set the wrapper view background as Transparent (this wrapper view is very important, we have to fake the effect on this wrapper view)
drag your scroll view into the wrapper view, and set your scroll view background as Transparent as well.
2.> set up all the outlets for scroll view, wrapper view and background image view
3.> You might also want to hide the nav bar shadow image, here is the code, just in case if you need it
self.navigationController.navigationBar.shadowImage = [[UIImage alloc] init];
4.> Then paste this method into your class
- (CALayer *)createViewMaskWithSize:(CGSize)size startGradientAt:(CGFloat)start endGradientAt:(CGFloat)end
{
CAGradientLayer *mask = [CAGradientLayer layer];
mask.anchorPoint = CGPointZero;
mask.startPoint = CGPointMake(0.5f, 0.0f);
mask.endPoint = CGPointMake(0.5f, 1.0f);
mask.colors = #[(id)[UIColor clearColor].CGColor, (id)[UIColor clearColor].CGColor, (id)[UIColor whiteColor].CGColor, (id)[UIColor whiteColor].CGColor];
mask.locations = #[#0.0, #(start/size.height), #(end/size.height), #1.0f];
mask.frame = CGRectMake(0, 0, size.width, size.height);
return mask;
}
The purpose for this method is to create a mask layer with a clear to white gradient on it.
5.> last step, simply add that to your wrapperView.layer.mask like this
// 64 in here is the position where the fade effect should start, and 80 is where the gradien should end
// you can change those 2 numbers and see different effects
self.scrollViewWrapperView.layer.mask = [self createViewMaskWithSize:self.scrollViewWrapperView.frame.size startGradientAt:64 endGradientAt:80];
The wrapper view is the key in this case, the nav bar won't work without it. and remember DO NOT put the background image view into the wrapper view, they should be on the same level, but background image under the wrapper view.
This is a very rough mock ups, but hope this gives you some ideas.
I have a UIView which includes a UIButton which is partially on UIView. I have a problem when I draw a border on my UIView. Please have a look at my screenshot:
You can see the border is above the UIButton, why? Can anybody suggest? Thanks
Thanks for aăâ, I found a solution.
Basically the border is always drawn on top of everything
What I did is:
Create a UIView with color of border
Create another UIView as the child the main UIView which is a little bit smaller than the first one. The color of this newly create UIView is the main color
Here is the code:
self.layer.cornerRadius = 15;
self.layer.masksToBounds = YES;
self.backView.layer.cornerRadius = 15;
self.backView.layer.masksToBounds = YES;
The result is:
It's more or less what I need although it's not perfect.
It could have to do with the order that the objects are drawn. In your storyboard's "Document Outline", views that are lower down in a view controller's outline are drawn later. Perhaps the button is not the last drawn view, like you want?
I have used UIColor colorWithPatternImage to get a tiled color. I set this as the background of my view. After this, any changes to view.layer.cornerRadius do not have any affect: it doesn't change the corner radius. I have also tried adding another subview to my view, setting that's background color to the pattern and using cornerRadius on my view to no avail.
How can I fix this behaviour?
Thanks for your time.
Set the clipsToBounds of the view to YES and it should work. I had the same issue.
Here is my snippet:
self.leftPanelView.layer.cornerRadius = 10;
self.leftPanelView.clipsToBounds = YES;
self.leftPanelView.backgroundColor = [UIColor colorWithPatternImage:[UIImage imageNamed:#"linePattern_gray.png"]];
which shows the linePattern_gray.png as the background patterned with a nice rounded corner.