I have the following code in my viewWillAppear in a modal uiviewcontroller.
I am including UIImage+ImageEffects.h to do the blurring of the background image in this example.
-(void) viewWillAppear:(BOOL)animated
{
[super viewWillAppear:NO];
// grab an image of our parent view
UIView *parentView = self.presentingViewController.view;
UIImage *parentViewImage = [self takeSnapshotOfView:parentView];
UIImage *blurredImage = nil;
//BLUR THE IMAGE
blurredImage = [self blurWithImageEffects:parentViewImage];
// insert an image view with a picture of the parent view at the back of our view's subview stack...
UIImageView *imageView = [[UIImageView alloc] initWithFrame:self.view.bounds];
imageView.image = blurredImage;
[self.view insertSubview:imageView atIndex:0];
}
[EDIT] Adding Blur Methods
- (UIImage *)takeSnapshotOfView:(UIView *)view
{
CGFloat reductionFactor = 1.5;
UIGraphicsBeginImageContext(CGSizeMake(view.frame.size.width/reductionFactor, view.frame.size.height/reductionFactor));
[view drawViewHierarchyInRect:CGRectMake(0, 0, view.frame.size.width/reductionFactor, view.frame.size.height/reductionFactor) afterScreenUpdates:YES];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return image;
}
- (UIImage *)blurWithImageEffects:(UIImage *)image
{
return [image applyBlurWithRadius:10 tintColor:[UIColor colorWithWhite:1 alpha:0.2] saturationDeltaFactor:1.5 maskImage:nil];
}
The code works fine and the background shows up blurry but it is really noticeably slow on iPad 3 with iOS 8. When the button to display this viewcontroller is tapped there is a pause before the viewcontroller slides up from the bottom. If I remove the blur the view controller slides up faster.
I tried putting the code in the viewDidAppear but then there is a noticeable white background displayed for a few seconds before the blur appears. But when in viewDidAppear the viewcontroller slides up immediately.
If I reduce the applyWithBlurRadius value this does not seem to reduce the time it takes to apply the blur.
Is there any way I can make it run faster?
GPUImage might solve your issue, Its fast and it doesn't put too much load on processing.
Link To Framework : https://github.com/BradLarson/GPUImage
Link to use GPUImage Blur
http://blog.bubbly.net/tag/gpu-image/
http://www.raywenderlich.com/60968/ios-7-blur-effects-gpuimage
However a reference is shown below which will give you the basic idea:
First prepare your view which is to blurred:
- (NSData *)PhotoForBlurring:(UIView *)view{
UIGraphicsBeginImageContextWithOptions(view.bounds.size, NO, 1.0);
[view.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
NSData * data = UIImagePNGRepresentation(image);
[data writeToFile:#"aName.png" atomically:YES];
return data; }
-(void)sharingScrapPage{
GPUImageiOSBlurFilter *blur = [[GPUImageiOSBlurFilter alloc]init];
blur.blurRadiusInPixels=2.0;
blur.downsampling=6.0;
[blurview removeFromSuperview];
blurview = [[UIImageView alloc]initWithFrame:getRectDisplay(0, 0, 480, 320)]; // Landscape Iphone 4S
UIImage *imageForBlurring=[UIImage imageWithData:[self PhotoForBlurring:self.view]];
NSData* pngdataForBlurring = UIImagePNGRepresentation (imageForBlurring);
UIImage* blurImage = [UIImage imageWithData:pngdataForBlurring];
blurImage=[blur imageByFilteringImage:blurImage];
blurview.image=blurImage;
[self.view addSubview:blurview];
[progressHUD removeFromSuperview];
progressHUD = [[ProgressHUD alloc]initWithFrame:getRectDisplay(190, 110, 100, 90)];
[blurview addSubview:progressHUD]; }
In my universal app,
I am setting an image on navigation bar...using **
objective c category...on UINavigationBar
**
The code works fine in ios 5.0 in iphone
*The code works fine in ios 4.3 in iPhone/iPad*
*But not working in **ios 5.0 iPad***
- (void) drawRect:(CGRect)rect
{
UIImage *image;
image = [UIImage imageNamed: #"Navigation.png"];
[image drawInRect:CGRectMake(0, 0, self.frame.size.width, self.frame.size.height)];
[self setTintColor:[UIColor clearColor]];
NSLog(#"Draw Rect");
}
To set a BG image for navigation bar in iOS 5 you can use the below code
if ([self.navigationController.navigationBar respondsToSelector:#selector( setBackgroundImage:forBarMetrics:)]){
[self.navigationController.navigationBar setBackgroundImage:[UIImage imageNamed:#"Navigation.png"] forBarMetrics:UIBarMetricsDefault];
}
But please keep in mind that this wont work in iOS 4. To make it work in both you also need to add a category to UINavigationBar
#implementation UINavigationBar (UINavigationBarCategory)
- (void)drawRect:(CGRect)rect {
UIImage *img = [UIImage imageNamed:#"Navigation.png"];
[img drawInRect:rect];
}
If you want to set the background application-wide you can use iOS5's UIAppearance.
[[UINavigationBar appearance] setBackgroundImage:X forBarMetrics:UIBarMetricsDefault];
[[UINavigationBar appearance] setBackgroundImage:X forBarMetrics:UIBarMetricsLandscape];
How do you customize UITableViews and the overall UX of an iOS app to use custom colors and textures, such as in Foodish?
That is a very open-ended question. They are doing a lot of different things. I'll address a few of them.
Custom Toolbar
They are creating a custom toolbar extension which uses an image as a background pattern. To do this, create a category on UINavigationBar
#implementation UINavigationBar(CustomBackground)
+ (UIImage *) bgImagePortrait {
static UIImage *image = nil;
if (image == nil) {
image = [[UIImage imageNamed:#"top_bar_portrait"] retain];
NSAssert(image, #"Image specified must be valid.");
}
return image;
}
+ (UIImage *) bgImageLandscape {
static UIImage *image = nil;
if (image == nil) {
image = [[UIImage imageNamed:#"top_bar_landscape"] retain];
NSAssert(image, #"Image specified must be valid.");
}
return image;
}
- (void) drawLayer:(CALayer *)layer inContext:(CGContextRef)ctx {
if ([self isMemberOfClass:[UINavigationBar class]] == NO) {
return;
}
UIImage *image = (self.frame.size.width > 320) ?
[UINavigationBar bgImageLandscape] : [UINavigationBar bgImagePortrait];
CGContextClip(ctx);
CGContextTranslateCTM(ctx, 0, image.size.height);
CGContextScaleCTM(ctx, 1.0, -1.0);
CGContextDrawImage(ctx, CGRectMake(0, 0, self.frame.size.width,
self.frame.size.height), image.CGImage);
}
Custom Toolbar Buttons
The buttons on the toolbars are just custom buttons with images on them. You can create a custom UIBarButtonItem using the initWithCustomView constructor:
[[UIBarButtonItem alloc] initWithCustomView:container]
Paging ScrollView
I'm not sure they are using a table view at all. It looks like a custom layout of a paging scroll view to me. Seems like it would be fairly straightforward to create a method that takes a collection of images and lays them out on the scroll page in a staggered layout.
how can i set the image in background of UItoolbar?
please give the answer in simple word and in sequence of steps.
Thanks
Use your custom toolbar by extending UIToolBar and override drawRect method.
#interface XToolBar : UIToolbar {
}
#end
And implementation :
#implementation XToolBar
- (void)drawRect:(CGRect)rect {
[[UIImage imageNamed:#"hede.png"] drawInRect:rect];
}
#end
#implementation UIToolbar (CustomImage)
- (void)drawRect:(CGRect)rect {
UIImage *image = [UIImage imageNamed: #"CustomImage.png"];
[image drawInRect:CGRectMake(0, 0, self.frame.size.width, self.frame.size.height)];
}
I try the following code, but it doesn't work.
[helloToolbar setBackgroundColor:[UIColor clearColor]];
To make a completely transparent toolbar, use the method described here. In a nutshell, create a new TransparentToolbar class that inherits from UIToolbar, and use that in place of UIToolbar.
TransarentToolbar.h
#interface TransparentToolbar : UIToolbar
#end
TransarentToolbar.m
#implementation TransparentToolbar
// Override draw rect to avoid
// background coloring
- (void)drawRect:(CGRect)rect {
// do nothing in here
}
// Set properties to make background
// translucent.
- (void) applyTranslucentBackground
{
self.backgroundColor = [UIColor clearColor];
self.opaque = NO;
self.translucent = YES;
}
// Override init.
- (id) init
{
self = [super init];
[self applyTranslucentBackground];
return self;
}
// Override initWithFrame.
- (id) initWithFrame:(CGRect) frame
{
self = [super initWithFrame:frame];
[self applyTranslucentBackground];
return self;
}
#end
(code from the blog post linked above)
In iOS 5, simply call setBackgroundImage and pass a transparent image.
Here's how I do it (I dynamically generate transparent image):
CGRect rect = CGRectMake(0, 0, 1, 1);
UIGraphicsBeginImageContext(rect.size);
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSetFillColorWithColor(context, [[UIColor clearColor] CGColor]);
CGContextFillRect(context, rect);
UIImage *transparentImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
[toolbar setBackgroundImage:transparentImage forToolbarPosition:UIToolbarPositionAny barMetrics:UIBarMetricsDefault];
The best you can do is using
[helloToolbar setBarStyle:UIBarStyleBlack];
[helloToolbar setTranslucent:YES];
This will get you a black but translucent toolbar.
Transparent (iOS 5.0):
[toolbar setBackgroundImage:[[UIImage alloc] init] forToolbarPosition:UIToolbarPositionAny barMetrics:UIBarMetricsDefault];
Translucent:
[toolbar setBarStyle:UIBarStyleBlack];
[toolbar setTranslucent:YES];
A cumulative solution for all devices, from oldest iOS 3.0 (iPhone 1) to newest iOS 6.1 (iPad mini).
#implementation UIToolbar (Extension)
- (void)drawRect:(CGRect)rect
{
if (CGColorGetAlpha(self.backgroundColor.CGColor) > 0.f)
{
[super drawRect:rect];
}
}
- (void)setTransparent
{
//iOS3+
self.backgroundColor = [UIColor clearColor];
//iOS5+
if ([self respondsToSelector:#selector(setBackgroundImage:forToolbarPosition:barMetrics:)])
{
[self setBackgroundImage:[[UIImage new] autorelease] forToolbarPosition:UIToolbarPositionAny barMetrics:UIBarMetricsDefault];
}
//iOS6+
if ([self respondsToSelector:#selector(setShadowImage:forToolbarPosition:)])
{
[self setShadowImage:[[UIImage new] autorelease] forToolbarPosition:UIToolbarPositionAny];
}
}
#end
When you want a transparent toolbar, call setTransparent on it.
When you want a non-transparent toolbar, set a backgroundColor of your choice or add an imageView by yourself.
Another solution would be to define a category for UIToolbar:
#implementation UIToolbar(Transparent)
-(void)drawRect:(CGRect)rect {
// do nothing in here
}
#end
In the IB set the toolbar as Black Translucent and non opaque.
We've just noticed that overriding drawRect doesn't work anymore with iOS 4.3. It's not called anymore (edit: seems to be only in Simulator). Instead drawLayer:inContext: is called.
A great solution was posted here
Now you can set each UIToolbar object transparent, by setting its tintColor to [UIColor clearColor] :)
With iOS 5 the following works:
UIToolbar *bar = [[UIToolbar alloc] initWithFrame:CGRectZero];
if (bar.subviews.count > 0)
[[[bar subviews] objectAtIndex:0] removeFromSuperview];
This is because the background is now a subview. This code is safe even with new iterations of iOS, but it may stop working. This is not private API usage, your app is safe to submit to the store.
Make sure you remove the backgroundView before adding any UIBarButtonItems to the bar. Or my code will not work.
I just tested the following with iOS 4.3 on simulator and phone, seems to work fine. Subclass UIToolbar, provide one method:
- (void)drawRect:(CGRect)rect
{
[[UIColor colorWithWhite:0 alpha:0.6f] set]; // or clearColor etc
CGContextFillRect(UIGraphicsGetCurrentContext(), rect);
}
toolbar.barStyle = UIBarStyleBlackTranslucent;
This works in iOS5.1 with pretty minimal effort. I am matching up the size, as only the background will have the same frame size as the toolbar itself. You could use other criteria, of course.
Enjoy.
Create a subclass of UIToolbar as follows:
.h:
#import <UIKit/UIKit.h>
#interface UIClearToolbar : UIToolbar
#end
.m:
#import "UIClearToolbar.h"
#implementation UIClearToolbar
- (void)layoutSubviews {
// super has already laid out the subviews before this call is made.
[self.subviews enumerateObjectsUsingBlock:^(UIView* obj, NSUInteger idx, BOOL *stop) {
if (CGSizeEqualToSize(self.frame.size, obj.frame.size) ||
self.frame.size.width <= obj.frame.size.width) { // on device, the background is BIGGER than the toolbar.) {
[obj removeFromSuperview];
*stop = YES;
}
}];
}
#end
Thanks #morais for your solution - here's the code translated to MonoTouch:
public class TransparentToolbar : UIToolbar
{
public TransparentToolbar()
{
init();
}
public TransparentToolbar(RectangleF frame) : base(frame)
{
init();
}
void init()
{
BackgroundColor=UIColor.Clear;
Opaque=false;
Translucent=true;
}
public override void Draw(RectangleF rect)
{
}
}