BTGlassScrollView

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This is a view for you to either use as-is or modify the source. The view comes loaded with the ability to:

1. Create a self contained view replicating the look and feel of one panel of Yahoo! Weather app
2. Blur the background image and/or transform them just the right amount without additional code form you
3. Customized the animation/blur/height/shadow/etc. with a chagne of a number in the header #define
4. Just work! like magic!

Background:
I have been a big fan of Yahoo! weather app. I highly respect the work they have done. I wanted to replicate and also generalize the approach for anyone to use and/or study. This was not associated with Yahoo! No source was lifted from Yahoo! So there will be a few subtle differences between BTGlassScrollView and Yahoo! weather app. For example, this view is built to stay under one navigation bar which in turns allows for "swipe to back" on iOS7.

Implementation:
The view is a subclass of a UIView. It contains 2 scrollViews, background and foreground. backgroundScrollView consists of 2 imageviews, normal and blurred. The alpha of the blurred one changes as the background scrolls. And the background scrolls as the foreground scrolls (at a different rate). The foregroundScrollView consists of maskLayers (gradient) and the foregroundView (which is whatever you want it to be). Between foreground and background, 2 shadowsLayer is added on the top and bottom to give a better readability.

How to use (Simple Version):

1. Import BTGlassScrollView.h
2. Create an instance of glassScrollViewwith - (id)initWithFrame:(CGRect)frame BackgroundImage:(UIImage *)backgroundImage blurredImage:(UIImage *)blurredImage viewDistanceFromBottom:(CGFloat)viewDistanceFromBottom foregroundView:(UIView *)foregroundView and add it as subview to whereever you need it to be
   2a. backgroundImage is essential, pick the right one makes all the difference
   2b. blurredImage is not neccessary but you can provide your own customed one
   2c. viewDistanceFromBottom is how much your foregroundView is visible from the bottom (like Yahoo! temperature)
   2d. foregroundView is your info view
3. Adjustment - due to generalization, you need to set the top padding to allow navigation bar/ status bar to get unmasked. Call - (void)setTopLayoutGuideLength:(CGFloat)topLayoutGuideLength where appropriate (Usually at viewWillLayoutSubviews in your view controller

Please view example project to get the idea of how to implement.

How to implement Yahoo! like horizontal Scroll:
To Be Added - it is in the example just not explained in words

Note: The example provided are mix of 3 * 2 flavor. 3 ways to create viewController and 2 ways to implement the view. Uncomment the code in Appdelegate to see the different ways of creating ViewController and change the #define SIMPLE_SAMPLE to see the two ways of implementing

3 ways to create viewController:

1. plain vanilla viewController
2. viewController with NavigationController
3. viewController as a second screen of NavigationController

2 ways to implement the view

1. simple implementation
2. complex horizontal scroll implementation

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Example 2 Note
It is not without its bug. I would be very glad if someone can help fixing it
Known issues:

1. the scrolling flickers at times (Will be addressed soon!)
2. some of the method is a hack (heed the warning of the comment)

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Copyright 2014 Byte

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.