我是IOS初学者。
我正在尝试使用paintcode生成的代码显示一个自定义按钮。我在 Storyboard 上拖动一个视图，然后将此通用视图类设置为我的自定义视图“GreenButton”。当我运行该应用程序时，该按钮不显示。我添加了 NSLogs 并且可以看到 drawRect 方法成功运行。
paintcode 生成的代码似乎包含了绘制按钮的所有内容。我只是使用 XCode 来调整我的视图。
我是否需要实现 initWithFrame 方法？
//
// GreenButton.m
// Test
//
// Created by Tim on 13.04.2013.
// Copyright (c) 2013 Tim. All rights reserved.
//
#import "GreenButton.h"
@implementation GreenButton
- (id)initWithFrame:(CGRect)frame {
self = [super initWithFrame:frame];
if (self) {
// setup the initial properties of the view
}
return self;
}
#pragma mark - Touch event overrides
// Only override drawRect: if you perform custom drawing.
// An empty implementation adversely affects performance during animation.
- (void)drawRect:(CGRect)rect
{
NSLog(@"drawRect enter");
//// General Declarations
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
CGContextRef context = UIGraphicsGetCurrentContext();
//// Color Declarations
UIColor* strokeColor = [UIColor colorWithRed: 0.419 green: 0.434 blue: 0.455 alpha: 1];
UIColor* baseColor = [UIColor colorWithRed: 0.218 green: 0.24 blue: 0.268 alpha: 1];
CGFloat baseColorRGBA[4];
[baseColor getRed: &baseColorRGBA[0] green: &baseColorRGBA[1] blue: &baseColorRGBA[2] alpha: &baseColorRGBA[3]];
UIColor* upperColor = [UIColor colorWithRed: (baseColorRGBA[0] * 0.8 + 0.2) green: (baseColorRGBA[1] * 0.8 + 0.2) blue: (baseColorRGBA[2] * 0.8 + 0.2) alpha: (baseColorRGBA[3] * 0.8 + 0.2)];
UIColor* lowerColor = [UIColor colorWithRed: (baseColorRGBA[0] * 0.9) green: (baseColorRGBA[1] * 0.9) blue: (baseColorRGBA[2] * 0.9) alpha: (baseColorRGBA[3] * 0.9 + 0.1)];
UIColor* lightUpColor = [UIColor colorWithRed: (baseColorRGBA[0] * 0.5 + 0.5) green: (baseColorRGBA[1] * 0.5 + 0.5) blue: (baseColorRGBA[2] * 0.5 + 0.5) alpha: (baseColorRGBA[3] * 0.5 + 0.5)];
UIColor* lightDownColor = [UIColor colorWithRed: (baseColorRGBA[0] * 0.8) green: (baseColorRGBA[1] * 0.8) blue: (baseColorRGBA[2] * 0.8) alpha: (baseColorRGBA[3] * 0.8 + 0.2)];
//// Gradient Declarations
NSArray* buttonGradientColors = [NSArray arrayWithObjects:
(id)upperColor.CGColor,
(id)lowerColor.CGColor, nil];
CGFloat buttonGradientLocations[] = {0, 1};
CGGradientRef buttonGradient = CGGradientCreateWithColors(colorSpace, (__bridge CFArrayRef)buttonGradientColors, buttonGradientLocations);
NSArray* overlayGradientColors = [NSArray arrayWithObjects:
(id)lightUpColor.CGColor,
(id)[UIColor clearColor].CGColor, nil];
CGFloat overlayGradientLocations[] = {0, 1};
CGGradientRef overlayGradient = CGGradientCreateWithColors(colorSpace, (__bridge CFArrayRef)overlayGradientColors, overlayGradientLocations);
NSArray* gradientColors = [NSArray arrayWithObjects:
(id)lightUpColor.CGColor,
(id)lightDownColor.CGColor, nil];
CGFloat gradientLocations[] = {0, 1};
CGGradientRef gradient = CGGradientCreateWithColors(colorSpace, (__bridge CFArrayRef)gradientColors, gradientLocations);
//// Shadow Declarations
UIColor* buttonShadow = [UIColor blackColor];
CGSize buttonShadowOffset = CGSizeMake(0.1, 1.1);
CGFloat buttonShadowBlurRadius = 2;
UIColor* textShadow = [UIColor blackColor];
CGSize textShadowOffset = CGSizeMake(0.1, -0.1);
CGFloat textShadowBlurRadius = 5;
//// Abstracted Attributes
NSString* textContent = @"Update";
//// Back Rectangle Drawing
UIBezierPath* backRectanglePath = [UIBezierPath bezierPathWithRoundedRect: CGRectMake(48, 53, 120, 23) cornerRadius: 4];
CGContextSaveGState(context);
CGContextSetShadowWithColor(context, buttonShadowOffset, buttonShadowBlurRadius, buttonShadow.CGColor);
CGContextBeginTransparencyLayer(context, NULL);
[backRectanglePath addClip];
CGContextDrawLinearGradient(context, gradient, CGPointMake(108, 53), CGPointMake(108, 76), 0);
CGContextEndTransparencyLayer(context);
CGContextRestoreGState(context);
//// Rounded Rectangle Drawing
UIBezierPath* roundedRectanglePath = [UIBezierPath bezierPathWithRoundedRect: CGRectMake(49, 54, 118, 21) cornerRadius: 3];
CGContextSaveGState(context);
[roundedRectanglePath addClip];
CGContextDrawLinearGradient(context, buttonGradient, CGPointMake(108, 54), CGPointMake(108, 75), 0);
CGContextRestoreGState(context);
//// Overlay Drawing
UIBezierPath* overlayPath = [UIBezierPath bezierPathWithRoundedRect: CGRectMake(48, 53, 120, 23) cornerRadius: 4];
CGContextSaveGState(context);
[overlayPath addClip];
CGContextDrawRadialGradient(context, overlayGradient,
CGPointMake(54.72, 38.09), 10,
CGPointMake(108, 11.46), 102.2,
kCGGradientDrawsBeforeStartLocation | kCGGradientDrawsAfterEndLocation);
CGContextRestoreGState(context);
//// Text Drawing
CGRect textRect = CGRectMake(55, 54, 104, 21);
UIBezierPath* textPath = [UIBezierPath bezierPathWithRect: textRect];
CGContextSaveGState(context);
CGContextSetShadowWithColor(context, textShadowOffset, textShadowBlurRadius, textShadow.CGColor);
CGContextBeginTransparencyLayer(context, NULL);
[textPath addClip];
CGContextDrawLinearGradient(context, buttonGradient, CGPointMake(107, 54), CGPointMake(107, 75), 0);
CGContextEndTransparencyLayer(context);
CGContextRestoreGState(context);
[strokeColor setStroke];
textPath.lineWidth = 1;
[textPath stroke];
CGContextSaveGState(context);
CGContextSetShadowWithColor(context, textShadowOffset, textShadowBlurRadius, textShadow.CGColor);
[[UIColor whiteColor] setFill];
[textContent drawInRect: textRect withFont: [UIFont boldSystemFontOfSize: [UIFont systemFontSize]] lineBreakMode: NSLineBreakByWordWrapping alignment: NSTextAlignmentCenter];
CGContextRestoreGState(context);
//// Cleanup
CGGradientRelease(buttonGradient);
CGGradientRelease(overlayGradient);
CGGradientRelease(gradient);
CGColorSpaceRelease(colorSpace);
NSLog(@"drawRect exit");
}
@end