├── README.markdown
├── STHorizontalPicker.h
├── STHorizontalPicker.m
└── screenshot.png


/README.markdown:
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1 | STHorizontalPicker
2 | ==================
3 | 
4 | Screenshot
5 | ----------
6 | 
7 | ![STHorizontalPicker](https://github.com/stackthread/STHorizontalPicker/raw/master/screenshot.png "STHorizontalPicker")


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/STHorizontalPicker.h:
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  1 | /*
  2 |  * Copyright 2011-2012 StackThread Software Ltd
  3 |  *
  4 |  * Licensed under the Apache License, Version 2.0 (the "License");
  5 |  * you may not use this file except in compliance with the License.
  6 |  * You may obtain a copy of the License at
  7 |  *
  8 |  * http://www.apache.org/licenses/LICENSE-2.0
  9 |  
 10 |  * Unless required by applicable law or agreed to in writing, software
 11 |  * distributed under the License is distributed on an "AS IS" BASIS,
 12 |  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 13 |  * See the License for the specific language governing permissions and
 14 |  * limitations under the License.
 15 |  */
 16 | 
 17 | #import <UIKit/UIKit.h>
 18 | #import <QuartzCore/QuartzCore.h>
 19 | 
 20 | 
 21 | @class STHorizontalPicker;
 22 | 
 23 | //================================
 24 | // Delegate protocol
 25 | //================================
 26 | @protocol STHorizontalPickerDelegate <NSObject>
 27 | 
 28 | @optional
 29 | - (CGFloat)minimumValueForPickerView:(STHorizontalPicker *)picker;
 30 | - (CGFloat)maximumValueForPickerView:(STHorizontalPicker *)picker;
 31 | - (NSUInteger)stepCountForPickerView:(STHorizontalPicker *)picker;
 32 | 
 33 | @required
 34 | - (void)pickerView:(STHorizontalPicker *)picker didSelectValue:(CGFloat)value;
 35 | 
 36 | @end
 37 | 
 38 | //================================
 39 | // UIColor category
 40 | //================================
 41 | @interface UIColor (STColorComponents)
 42 | - (CGFloat)red;
 43 | - (CGFloat)green;
 44 | - (CGFloat)blue;
 45 | - (CGFloat)alpha;
 46 | @end
 47 | 
 48 | 
 49 | //================================
 50 | // STHorizontalPicker interface
 51 | //================================
 52 | @interface STHorizontalPicker : UIView <UIScrollViewDelegate> {
 53 |     CGFloat value;
 54 |     
 55 |     NSUInteger steps;
 56 |     CGFloat minimumValue;
 57 |     CGFloat maximumValue;
 58 |     
 59 |     id delegate;
 60 |     
 61 |     UIColor *borderColor;
 62 |     CGFloat fontSize;
 63 |     
 64 |     @private
 65 |     CGFloat scale; // Drawing scale    
 66 | }
 67 | 
 68 | @property (nonatomic, retain) NSString *name;
 69 | 
 70 | - (void)snapToMarkerAnimated:(BOOL)animated;
 71 | 
 72 | - (CGFloat)minimumValue;
 73 | - (void)setMinimumValue:(CGFloat)newMin;
 74 | 
 75 | - (CGFloat)maximumValue;
 76 | - (void)setMaximumValue:(CGFloat)newMax;
 77 | 
 78 | - (NSUInteger)steps;
 79 | - (void)setSteps:(NSUInteger)newSteps;
 80 | 
 81 | - (CGFloat)value;
 82 | - (void)setValue:(CGFloat)newValue;
 83 | 
 84 | - (UIColor *)borderColor;
 85 | - (void)setBorderColor:(UIColor *)newBorderColor;
 86 | 
 87 | - (CGFloat)fontSize;
 88 | - (void)setFontSize:(CGFloat)newFontSize;
 89 | 
 90 | - (id)delegate;
 91 | - (void)setDelegate:(id<STHorizontalPickerDelegate>)newDelegate;
 92 | - (void)callDelegateWithNewValueFromOffset:(CGFloat)offset;
 93 | 
 94 | @end
 95 | 
 96 | 
 97 | 
 98 | //================================
 99 | // STPointerLayerDelegate interface
100 | //================================
101 | @interface STPointerLayerDelegate : NSObject {}
102 | 
103 | - (void)drawLayer:(CALayer *)layer inContext:(CGContextRef)context;
104 | 
105 | @end


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/STHorizontalPicker.m:
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  1 | /*
  2 |  * Copyright 2011-2012 StackThread Software Ltd
  3 |  *
  4 |  * Licensed under the Apache License, Version 2.0 (the "License");
  5 |  * you may not use this file except in compliance with the License.
  6 |  * You may obtain a copy of the License at
  7 |  *
  8 |  * http://www.apache.org/licenses/LICENSE-2.0
  9 |  
 10 |  * Unless required by applicable law or agreed to in writing, software
 11 |  * distributed under the License is distributed on an "AS IS" BASIS,
 12 |  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 13 |  * See the License for the specific language governing permissions and
 14 |  * limitations under the License.
 15 |  */
 16 | 
 17 | #import "STHorizontalPicker.h"
 18 | 
 19 | const int DISTANCE_BETWEEN_ITEMS = 100;
 20 | const int TEXT_LAYER_WIDTH = 40;
 21 | const int NUMBER_OF_ITEMS = 15;
 22 | const float FONT_SIZE = 16.0f;
 23 | const float POINTER_WIDTH = 10.0f;
 24 | const float POINTER_HEIGHT = 7.0f;
 25 | 
 26 | //================================
 27 | // UIColor category
 28 | //================================
 29 | @implementation UIColor (STColorComponents)
 30 | 
 31 | - (CGColorSpaceModel)colorSpaceModel {
 32 | 	return CGColorSpaceGetModel(CGColorGetColorSpace(self.CGColor));
 33 | }
 34 | 
 35 | - (CGFloat)red {
 36 | 	const CGFloat *c = CGColorGetComponents(self.CGColor);
 37 | 	return c[0];
 38 | }
 39 | 
 40 | - (CGFloat)green {
 41 | 	const CGFloat *c = CGColorGetComponents(self.CGColor);
 42 |     if (self.colorSpaceModel == kCGColorSpaceModelMonochrome) return c[0];
 43 | 	return c[1];
 44 | }
 45 | 
 46 | - (CGFloat)blue {
 47 | 	const CGFloat *c = CGColorGetComponents(self.CGColor);
 48 | 	if (self.colorSpaceModel == kCGColorSpaceModelMonochrome) return c[0];
 49 | 	return c[2];
 50 | }
 51 | 
 52 | - (CGFloat)alpha {
 53 |     return CGColorGetAlpha(self.CGColor);
 54 | }
 55 | 
 56 | @end
 57 | 
 58 | 
 59 | 
 60 | 
 61 | 
 62 | //================================
 63 | // STHorizontalPicker
 64 | //================================
 65 | 
 66 | @interface STHorizontalPicker ()
 67 | 
 68 | // Private properties
 69 | 
 70 | @property (nonatomic, retain) UIScrollView *scrollView;
 71 | @property (nonatomic, retain) UIView *scrollViewMarkerContainerView;
 72 | @property (nonatomic, retain) NSMutableArray *scrollViewMarkerLayerArray;
 73 | @property (nonatomic, retain) CALayer *pointerLayer;
 74 | 
 75 | @end;
 76 |     
 77 | @implementation STHorizontalPicker
 78 | 
 79 | @synthesize scrollView, scrollViewMarkerContainerView, scrollViewMarkerLayerArray, name, pointerLayer;
 80 | 
 81 | - (id)initWithFrame:(CGRect)frame
 82 | {
 83 |     self = [super initWithFrame:frame];
 84 |     if (self) {        
 85 |         steps = 15;
 86 |         
 87 |         float leftPadding = self.frame.size.width/2;
 88 |         float rightPadding = leftPadding;
 89 |         float contentWidth = leftPadding + (steps * DISTANCE_BETWEEN_ITEMS) + rightPadding + TEXT_LAYER_WIDTH / 2;
 90 |         
 91 |         scale = [[UIScreen mainScreen] scale];
 92 |         
 93 |         if ([self respondsToSelector:@selector(setContentScaleFactor:)]) {
 94 |             self.contentScaleFactor = scale;
 95 |         }
 96 |         
 97 |         // Ensures that the corners are transparent
 98 |         self.backgroundColor = [UIColor clearColor];
 99 |         
100 |         self.scrollView = [[UIScrollView alloc] initWithFrame:CGRectMake(0.0f, 0.0f, self.frame.size.width, self.frame.size.height)];
101 |         self.scrollView.contentSize = CGSizeMake(contentWidth, self.frame.size.height);
102 |         self.scrollView.layer.cornerRadius = 8.0f;
103 |         self.scrollView.layer.borderWidth = 1.0f;
104 |         self.scrollView.layer.borderColor = borderColor.CGColor ? borderColor.CGColor : [UIColor grayColor].CGColor;
105 |         self.scrollView.backgroundColor = [UIColor colorWithRed:0.95 green:0.95 blue:0.95 alpha:1.0];
106 |         self.scrollView.showsVerticalScrollIndicator = NO;
107 |         self.scrollView.showsHorizontalScrollIndicator = NO;        
108 |         self.scrollView.pagingEnabled = NO;
109 |         self.scrollView.delegate = self;
110 |         
111 |         self.scrollViewMarkerContainerView = [[UIView alloc] initWithFrame:CGRectMake(0.0f, 0.0f, contentWidth, self.frame.size.height)];
112 |         self.scrollViewMarkerLayerArray = [NSMutableArray arrayWithCapacity:steps];
113 |         
114 |         fontSize = 16.0;
115 |         
116 |         for (int i = 0; i <= steps; i++) {
117 |             CATextLayer *textLayer = [CATextLayer layer];
118 |             textLayer.contentsScale = scale;
119 |             textLayer.frame = CGRectIntegral(CGRectMake(leftPadding + i * DISTANCE_BETWEEN_ITEMS, self.frame.size.height/2 - self.fontSize / 2 + 1, TEXT_LAYER_WIDTH, 40));
120 |             textLayer.foregroundColor = [UIColor blackColor].CGColor;
121 |             textLayer.alignmentMode = kCAAlignmentCenter;
122 |             textLayer.fontSize = self.fontSize;
123 |             
124 |             textLayer.string = [NSString stringWithFormat:@"%.1f", (float) i + 1];
125 |             [self.scrollViewMarkerLayerArray addObject:textLayer];
126 |             [self.scrollViewMarkerContainerView.layer addSublayer:textLayer];
127 |         }
128 |         
129 |         [self.scrollView addSubview:self.scrollViewMarkerContainerView];        
130 |         [self addSubview:self.scrollView];
131 |         [self snapToMarkerAnimated:NO];
132 | 
133 |         CAGradientLayer *dropshadowLayer = [CAGradientLayer layer];
134 |         dropshadowLayer.contentsScale = scale;
135 |         dropshadowLayer.cornerRadius = 8.0f;
136 |         dropshadowLayer.startPoint = CGPointMake(0.0f, 0.0f);
137 |         dropshadowLayer.endPoint = CGPointMake(0.0f, 1.0f);
138 |         dropshadowLayer.opacity = 1.0;
139 |         dropshadowLayer.frame = CGRectMake(1.0f, 1.0f, self.frame.size.width - 2.0, self.frame.size.height - 2.0);
140 |         dropshadowLayer.locations = [NSArray arrayWithObjects:
141 |                                    [NSNumber numberWithFloat:0.0f],
142 |                                    [NSNumber numberWithFloat:0.05f],
143 |                                    [NSNumber numberWithFloat:0.2f],
144 |                                    [NSNumber numberWithFloat:0.8f],
145 |                                    [NSNumber numberWithFloat:0.95f],                                   
146 |                                    [NSNumber numberWithFloat:1.0f], nil];
147 |         dropshadowLayer.colors = [NSArray arrayWithObjects:
148 |                                 (id)[[UIColor colorWithRed:0.05f green:0.05f blue:0.05f alpha:0.75] CGColor], 
149 |                                 (id)[[UIColor colorWithRed:0.25f green:0.25f blue:0.25f alpha:0.55] CGColor], 
150 |                                 (id)[[UIColor colorWithRed:1.0f green:1.0f blue:1.0f alpha:0.05] CGColor], 
151 |                                 (id)[[UIColor colorWithRed:1.0f green:1.0f blue:1.0f alpha:0.05] CGColor], 
152 |                                 (id)[[UIColor colorWithRed:0.25f green:0.25f blue:0.25f alpha:0.55] CGColor],
153 |                                 (id)[[UIColor colorWithRed:0.05f green:0.05f blue:0.05f alpha:0.75] CGColor], nil];
154 |         
155 |         [self.layer insertSublayer:dropshadowLayer above:self.scrollView.layer];
156 |         
157 |         CAGradientLayer *gradientLayer = [CAGradientLayer layer];
158 |         gradientLayer.contentsScale = scale;
159 |         gradientLayer.cornerRadius = 8.0f;
160 |         gradientLayer.startPoint = CGPointMake(0.0f, 0.0f);
161 |         gradientLayer.endPoint = CGPointMake(1.0f, 0.0f);
162 |         gradientLayer.opacity = 1.0;
163 |         gradientLayer.frame = CGRectMake(1.0f, 1.0f, self.frame.size.width - 2.0, self.frame.size.height - 2.0);
164 |         gradientLayer.locations = [NSArray arrayWithObjects:
165 |                                    [NSNumber numberWithFloat:0.0f],
166 |                                    [NSNumber numberWithFloat:0.05f],
167 |                                    [NSNumber numberWithFloat:0.3f],
168 |                                    [NSNumber numberWithFloat:0.7f],
169 |                                    [NSNumber numberWithFloat:0.95f],                                   
170 |                                    [NSNumber numberWithFloat:1.0f], nil];
171 |         gradientLayer.colors = [NSArray arrayWithObjects:
172 |                                 (id)[[UIColor colorWithRed:0.05f green:0.05f blue:0.05f alpha:0.95] CGColor], 
173 |                                 (id)[[UIColor colorWithRed:0.25f green:0.25f blue:0.25f alpha:0.8] CGColor], 
174 |                                 (id)[[UIColor colorWithRed:1.0f green:1.0f blue:1.0f alpha:0.1] CGColor], 
175 |                                 (id)[[UIColor colorWithRed:1.0f green:1.0f blue:1.0f alpha:0.1] CGColor], 
176 |                                 (id)[[UIColor colorWithRed:0.25f green:0.25f blue:0.25f alpha:0.8] CGColor],
177 |                                 (id)[[UIColor colorWithRed:0.05f green:0.05f blue:0.05f alpha:0.95] CGColor], nil];
178 |         [self.layer insertSublayer:gradientLayer above:dropshadowLayer];
179 |         
180 |         self.pointerLayer = [CALayer layer];
181 |         [self.pointerLayer setValue:[NSNumber numberWithFloat:[borderColor red]] forKey:@"borderRed"];
182 |         [self.pointerLayer setValue:[NSNumber numberWithFloat:[borderColor green]] forKey:@"borderGreen"];
183 |         [self.pointerLayer setValue:[NSNumber numberWithFloat:[borderColor blue]] forKey:@"borderBlue"];
184 |         [self.pointerLayer setValue:[NSNumber numberWithFloat:[borderColor alpha]] forKey:@"borderAlpha"];        
185 |         self.pointerLayer.opacity = 1.0;
186 |         self.pointerLayer.contentsScale = scale;
187 |         self.pointerLayer.frame = CGRectMake(0.0f, 0.0f, self.frame.size.width, self.frame.size.height);
188 |         self.pointerLayer.delegate = [[[STPointerLayerDelegate alloc] init] autorelease];
189 |         [self.layer insertSublayer:self.pointerLayer above:gradientLayer];
190 |         [self.pointerLayer setNeedsDisplay];
191 |     }
192 |     return self;
193 | }
194 | 
195 | - (void)scrollViewDidEndDragging:(UIScrollView *)scrollView willDecelerate:(BOOL)decelerate {
196 |     [self snapToMarkerAnimated:YES];
197 |     if (delegate && [delegate respondsToSelector:@selector(pickerView:didSelectValue:)]) {
198 |         [self callDelegateWithNewValueFromOffset:[self.scrollView contentOffset].x];
199 |     }
200 | }
201 | 
202 | - (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView {
203 |     [self snapToMarkerAnimated:YES];
204 |     if (delegate && [delegate respondsToSelector:@selector(pickerView:didSelectValue:)]) {
205 |         [self callDelegateWithNewValueFromOffset:[self.scrollView contentOffset].x];
206 |     }    
207 | }
208 | 
209 | - (void)callDelegateWithNewValueFromOffset:(CGFloat)offset {
210 | 
211 |     CGFloat itemWidth = (float) DISTANCE_BETWEEN_ITEMS;
212 |     
213 |     CGFloat offSet = offset / itemWidth;
214 |     NSUInteger target = (NSUInteger)(offSet + 0.35f);
215 |     target = target > steps ? steps - 1 : target;
216 |     CGFloat newValue = target * (maximumValue - minimumValue) / steps + minimumValue;
217 |     
218 |     [delegate pickerView:self didSelectValue:newValue];
219 |     
220 | }
221 | 
222 | - (void)snapToMarkerAnimated:(BOOL)animated {
223 |     CGFloat itemWidth = (float)DISTANCE_BETWEEN_ITEMS;
224 |     CGFloat position = [self.scrollView contentOffset].x;
225 | 
226 |     if (position < self.scrollViewMarkerContainerView.frame.size.width - self.frame.size.width / 2) {
227 |         CGFloat newPosition = 0.0f;
228 |         CGFloat offSet = position / itemWidth;
229 |         NSUInteger target = (NSUInteger)(offSet + 0.35f);
230 |         target = target > steps ? steps - 1 : target;
231 |         newPosition = target * itemWidth + TEXT_LAYER_WIDTH / 2;
232 |         [self.scrollView setContentOffset:CGPointMake(newPosition, 0.0f) animated:animated];
233 |     }
234 | }
235 | 
236 | - (void)removeAllMarkers {
237 |     for (id marker in self.scrollViewMarkerLayerArray) {
238 |         [(CATextLayer *)marker removeFromSuperlayer];
239 |     }
240 |     [self.scrollViewMarkerLayerArray removeAllObjects];
241 | }
242 | 
243 | - (void)setupMarkers {
244 |     [self removeAllMarkers];
245 |     
246 |     // Calculate the new size of the content
247 |     float leftPadding = self.frame.size.width / 2;
248 |     float rightPadding = leftPadding;
249 |     float contentWidth = leftPadding + (steps * DISTANCE_BETWEEN_ITEMS) + rightPadding + TEXT_LAYER_WIDTH / 2;
250 |     self.scrollView.contentSize = CGSizeMake(contentWidth, self.frame.size.height);
251 |     
252 |     // Set the size of the marker container view
253 |     [self.scrollViewMarkerContainerView setFrame:CGRectMake(0.0f, 0.0f, contentWidth, self.frame.size.height)];
254 |     
255 |     // Configure the new markers
256 |     self.scrollViewMarkerLayerArray = [NSMutableArray arrayWithCapacity:steps];
257 |     for (int i = 0; i <= steps; i++) {
258 |         CATextLayer *textLayer = [CATextLayer layer];
259 |         textLayer.contentsScale = scale;
260 |         textLayer.frame = CGRectIntegral(CGRectMake(leftPadding + i*DISTANCE_BETWEEN_ITEMS, self.frame.size.height / 2 - fontSize / 2 + 1, TEXT_LAYER_WIDTH, 40));
261 |         textLayer.foregroundColor = [UIColor blackColor].CGColor;
262 |         textLayer.alignmentMode = kCAAlignmentCenter;
263 |         textLayer.fontSize = fontSize;
264 |         
265 |         textLayer.string = [NSString stringWithFormat:@"%.1f", (float) minimumValue + i * (maximumValue - minimumValue) / steps];
266 |         [self.scrollViewMarkerLayerArray addObject:textLayer];
267 |         [self.scrollViewMarkerContainerView.layer addSublayer:textLayer];
268 |     }
269 | }
270 | 
271 | - (CGFloat)minimumValue {
272 |     return minimumValue;
273 | }
274 | 
275 | - (void)setMinimumValue:(CGFloat)newMin {
276 |     minimumValue = newMin;
277 |     [self setupMarkers];
278 | }
279 | 
280 | - (CGFloat)maximumValue {
281 |     return maximumValue;
282 | }
283 | 
284 | - (void)setMaximumValue:(CGFloat)newMax {
285 |     maximumValue = newMax;
286 |     [self setupMarkers];
287 | }
288 | 
289 | - (NSUInteger)steps {
290 |     return steps;
291 | }
292 | 
293 | - (void)setSteps:(NSUInteger)newSteps {
294 |     steps = newSteps;
295 |     [self setupMarkers];
296 | }
297 | 
298 | - (CGFloat)value {
299 |     return value;
300 | }
301 | 
302 | - (UIColor *)borderColor {
303 |     return borderColor;
304 | }
305 | 
306 | - (void)setBorderColor:(UIColor *)newBorderColor {
307 |     if (newBorderColor != borderColor)
308 |     {
309 |         [newBorderColor retain];
310 |         [borderColor release];
311 |         borderColor = newBorderColor;
312 | 
313 |         [self.pointerLayer setValue:[NSNumber numberWithFloat:[borderColor red]] forKey:@"borderRed"];
314 |         [self.pointerLayer setValue:[NSNumber numberWithFloat:[borderColor green]] forKey:@"borderGreen"];
315 |         [self.pointerLayer setValue:[NSNumber numberWithFloat:[borderColor blue]] forKey:@"borderBlue"];
316 |         [self.pointerLayer setValue:[NSNumber numberWithFloat:[borderColor alpha]] forKey:@"borderAlpha"];
317 |         [self.pointerLayer setNeedsDisplay];
318 |         
319 |         self.scrollView.layer.borderColor = borderColor.CGColor;
320 |     }
321 | }
322 | 
323 | - (CGFloat)fontSize {
324 |     return fontSize;
325 | }
326 | 
327 | - (void)setFontSize:(CGFloat)newFontSize {
328 |     fontSize = newFontSize;
329 |     [self setupMarkers];
330 | }
331 | 
332 | - (void)setValue:(CGFloat)newValue {
333 |     value = newValue > maximumValue ? maximumValue : newValue;
334 |     value = newValue < minimumValue ? minimumValue : newValue;
335 |     
336 |     CGFloat itemWidth = (float) DISTANCE_BETWEEN_ITEMS;
337 |     CGFloat xValue = (newValue - minimumValue) / ((maximumValue-minimumValue) / steps) * itemWidth + TEXT_LAYER_WIDTH / 2;
338 |         
339 |     [self.scrollView setContentOffset:CGPointMake(xValue, 0.0f) animated:NO];
340 | }
341 | 
342 | - (id)delegate {
343 |     return delegate;
344 | }
345 | 
346 | - (void)setDelegate:(id<STHorizontalPickerDelegate>)newDelegate {
347 |     delegate = newDelegate;
348 |     
349 |     BOOL needsReset = FALSE;
350 |     
351 |     if ([delegate respondsToSelector:@selector(minimumValueForPickerView:)]) {
352 |         minimumValue = [delegate minimumValueForPickerView:self];
353 |         needsReset = TRUE;
354 |     }
355 |     if ([delegate respondsToSelector:@selector(maximumValueForPickerView:)]) {
356 |         maximumValue = [delegate maximumValueForPickerView:self];
357 |         needsReset = TRUE;
358 |     }
359 |     if ([delegate respondsToSelector:@selector(stepCountForPickerView:)]) {
360 |         steps = [delegate stepCountForPickerView:self];
361 |         needsReset = TRUE;
362 |     }
363 |     
364 |     if (needsReset) {
365 |         [self setupMarkers];
366 |     }
367 | }
368 | 
369 | 
370 | - (void)dealloc
371 | {
372 |     [scrollView release];
373 |     [scrollViewMarkerContainerView release];
374 |     [scrollViewMarkerLayerArray release];
375 |     [pointerLayer release];
376 |     [super dealloc];
377 | }
378 | 
379 | @end
380 | 
381 | 
382 | //================================
383 | // STPointerLayerDelegate
384 | //================================
385 | 
386 | @implementation STPointerLayerDelegate
387 | 
388 | - (void)drawLayer:(CALayer *)layer inContext:(CGContextRef)context {
389 |     CGContextSaveGState(context);
390 | 
391 |     CGContextSetLineWidth(context, 2.0);
392 | 	CGContextSetRGBStrokeColor(context, [[layer valueForKey:@"borderRed"] floatValue], [[layer valueForKey:@"borderGreen"] floatValue], [[layer valueForKey:@"borderBlue"] floatValue], [[layer valueForKey:@"borderAlpha"] floatValue]);
393 |     CGContextSetRGBFillColor(context, [[layer valueForKey:@"borderRed"] floatValue], [[layer valueForKey:@"borderGreen"] floatValue], [[layer valueForKey:@"borderBlue"] floatValue], [[layer valueForKey:@"borderAlpha"] floatValue]);
394 |     
395 |     CGContextSetShadowWithColor(context, CGSizeMake(0, 2), 3.0, [UIColor colorWithRed:0.0 green:0.0 blue:0.0 alpha:0.3].CGColor);
396 |     
397 |     CGContextMoveToPoint(context, layer.frame.size.width / 2 - POINTER_WIDTH / 2, 0);
398 |     CGContextAddLineToPoint(context, layer.frame.size.width / 2, POINTER_HEIGHT);
399 |     CGContextAddLineToPoint(context, layer.frame.size.width / 2 + POINTER_WIDTH / 2, 0);    
400 |     CGContextFillPath(context);
401 |     CGContextStrokePath(context);
402 |     
403 |     CGContextSetShadowWithColor(context, CGSizeMake(0, -2), 3.0, [UIColor colorWithRed:0.0 green:0.0 blue:0.0 alpha:0.3].CGColor);
404 |     
405 |     CGContextMoveToPoint(context, layer.frame.size.width / 2 - POINTER_WIDTH / 2, layer.frame.size.height);
406 |     CGContextAddLineToPoint(context, layer.frame.size.width / 2, layer.frame.size.height - POINTER_HEIGHT);
407 |     CGContextAddLineToPoint(context, layer.frame.size.width / 2 + POINTER_WIDTH / 2, layer.frame.size.height);    
408 |     CGContextFillPath(context);
409 |     CGContextStrokePath(context);
410 |     
411 |     CGContextRestoreGState(context);
412 | }
413 | 
414 | @end


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/screenshot.png:
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https://raw.githubusercontent.com/stackthread/STHorizontalPicker/3f69c778374bfeda10e69b801483a3ff2d069735/screenshot.png


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