IOS水晶图片制作

头文件：

#include <CoreGraphics/CoreGraphics.h>//绘制方式常量//一个矩形区域#define FS_DRAW_REGION_RECT (1 << 31)//左上角圆角#define FS_DRAW_REGION_LEFT_TOP_RADIUS (1)//右上角圆角#define FS_DRAW_REGION_RIGHT_TOP_RADIUS (1 << 1)//右下角圆角#define FS_DRAW_REGION_RIGHT_BOTTOM_RADIUS (1 << 2)//左下角圆角#define FS_DRAW_REGION_LEFT_BOTTOM_RADIUS (1 << 3)//四周圆角#define FS_DRAW_REGION_ROUND_RECT (FS_DRAW_REGION_LEFT_TOP_RADIUS | FS_DRAW_REGION_RIGHT_TOP_RADIUS | FS_DRAW_REGION_RIGHT_BOTTOM_RADIUS | FS_DRAW_REGION_LEFT_BOTTOM_RADIUS)//从上往下#define FS_LIGHT_FROM_TOP_TO_BOTTOM (1 << 8)//从左往右#define FS_LIGHT_FROM_LEFT_TO_RIGHT (1 << 9)//从下往上#define FS_LIGHT_FROM_BOTTOM_TO_TOP (1 << 10)//从右往左#define FS_LIGHT_FROM_RIGHT_TO_LEFT (1 << 11)//从里往外#define FS_LIGHT_FROM_INNER_TO_OUTER (1 << 12)//往外往里#define FS_LIGHT_FROM_OUTER_TO_INNER (1 << 13)#define FS_ARROW_UP (1)#define FS_ARROW_DOWN (1 << 1)#define FS_ARROW_LEFT (1 << 2)#define FS_ARROW_RIGHT (1 << 3)//文本位置#define TEXT_ALIGN_LEFT (1)#define TEXT_ALIGN_RIGHT (2)#define TEXT_ALIGN_TOP (3)#define TEXT_ALIGN_BOTTOM (4)//矩形渐变方向#define GRADIENT_RECT_FROM_TOP_TO_BOTTOM (1)#define GRADIENT_RECT_FROM_BOTTOM_TO_TOP (2)#define GRADIENT_RECT_FROM_LEFT_TO_RIGHT (3)#define GRADIENT_RECT_FROM_RIGHT_TO_LEFT (4)////////////////////////////////////////////////////////////////////函数说明：FOUNDATION_EXTERN//////////////////////////////////////////////////////////////////FOUNDATION_EXTERN void buildPathForRect(CGContextRef context, CGRect rect, CGFloat radius, NSUInteger radiusflag);FOUNDATION_EXTERN void drawLightForPath(CGContextRef context, CGRect rect, NSUInteger lightFlag, CGGradientRef gradient, CGFloat startRadius, CGFloat endRadius);FOUNDATION_EXTERN void drawCrystalRect(CGContextRef context, CGRect rect, CGFloat radius, const CGFloat *components, NSUInteger componentCount);FOUNDATION_EXTERN UIImage *createImageWithRect(CGRect rect, CGFloat radius, const CGFloat *components, NSUInteger componentCount);FOUNDATION_EXTERN void drawNavigatorArrow(CGContextRef context, CGRect rect, NSUInteger arrowDirection, const CGFloat *components, NSUInteger componentCount);FOUNDATION_EXTERN UIImage *createNavigatorArrowWithRect(CGRect rect, NSUInteger arrowDirection, CGFloat boundSpace, const CGFloat *components, NSUInteger componentCount);FOUNDATION_EXTERN void drawImageWithRect(CGContextRef context, CGRect rect, UIImage *image);FOUNDATION_EXTERN UIImage *scaleImage(UIImage *source, CGSize destSize);FOUNDATION_EXTERN UIImage *drawImageAndTextInRect(CGRect rect, UIImage *source, NSString *text, NSInteger textAlign);//FOUNDATION_EXTERN void drawButtonImage//还得加入参数，抽取成为一个函数FOUNDATION_EXTERN UIImage *createImageInRectWithGradient(CGRect rect, CGFloat radius, const CGFloat *components, NSUInteger componentCount, CGFloat borderWidth);FOUNDATION_EXTERN void drawGradientInRect(CGRect rect, CGContextRef context, CGColorSpaceRef colorSpace, const CGFloat *components, NSUInteger componentCount, NSUInteger directFlag);FOUNDATION_EXTERN void drawTopGradientInRect(CGRect rect, CGContextRef context, CGColorSpaceRef colorSpace);FOUNDATION_EXTERN void drawBottomGradientInRect(CGRect rect, CGContextRef context, CGColorSpaceRef colorSpace);FOUNDATION_EXTERN void drawGradientInRectWithSingleColor(CGRect rect, CGFloat radius, CGFloat borderWidth, CGContextRef context, CGColorSpaceRef colorSpace, const CGFloat *components, NSUInteger componentCount, NSUInteger directFlag);

.mm 文件

#include "FSGraphicsEx.h"#define RGB_ADDTION (30.0f / 255.0f)typedef void(* DRAW_GRADIENT_FUNC)(CGContextRef, CGRect, CGColorSpaceRef, CGFloat *, CGFloat, NSUInteger);void buildPathForRect(CGContextRef context, CGRect rect, CGFloat radius, NSUInteger radiusflag) {if ((radiusflag & FS_DRAW_REGION_RECT) == FS_DRAW_REGION_RECT || radius == 0) {#ifdef MYDEBUGNSLog(@"FS_DRAW_REGION_RECT");#endifCGContextMoveToPoint(context, CGRectGetMinX(rect), CGRectGetMinY(rect));CGContextAddLineToPoint(context, CGRectGetMaxX(rect), CGRectGetMinY(rect));CGContextAddLineToPoint(context, CGRectGetMaxX(rect), CGRectGetMaxY(rect));CGContextAddLineToPoint(context, CGRectGetMinX(rect), CGRectGetMaxY(rect));CGContextClosePath(context);} else {//左上CGContextMoveToPoint(context, CGRectGetMinX(rect), CGRectGetMidY(rect));if ((radiusflag & FS_DRAW_REGION_LEFT_TOP_RADIUS) == FS_DRAW_REGION_LEFT_TOP_RADIUS) {#ifdef MYDEBUGNSLog(@"FS_DRAW_REGION_LEFT_TOP_RADIUS");#endifCGContextAddArcToPoint(context, CGRectGetMinX(rect), CGRectGetMinY(rect), CGRectGetMidX(rect), CGRectGetMinY(rect), radius);} else {CGContextAddLineToPoint(context, CGRectGetMinX(rect), CGRectGetMinY(rect));}CGContextAddLineToPoint(context, CGRectGetMidX(rect), CGRectGetMinY(rect));//右上if ((radiusflag & FS_DRAW_REGION_RIGHT_TOP_RADIUS) == FS_DRAW_REGION_RIGHT_TOP_RADIUS) {#ifdef MYDEBUGNSLog(@"FS_DRAW_REGION_RIGHT_TOP_RADIUS");#endifCGContextAddArcToPoint(context, CGRectGetMaxX(rect), CGRectGetMinY(rect), CGRectGetMaxX(rect), CGRectGetMidY(rect), radius);} else {CGContextAddLineToPoint(context, CGRectGetMaxX(rect), CGRectGetMinY(rect));}CGContextAddLineToPoint(context, CGRectGetMaxX(rect), CGRectGetMidY(rect));//右下if ((radiusflag & FS_DRAW_REGION_RIGHT_BOTTOM_RADIUS) == FS_DRAW_REGION_RIGHT_BOTTOM_RADIUS) {#ifdef MYDEBUGNSLog(@"FS_DRAW_REGION_RIGHT_BOTTOM_RADIUS");#endifCGContextAddArcToPoint(context, CGRectGetMaxX(rect), CGRectGetMaxY(rect), CGRectGetMidX(rect), CGRectGetMaxY(rect), radius);} else {CGContextAddLineToPoint(context, CGRectGetMaxX(rect), CGRectGetMaxY(rect));}CGContextAddLineToPoint(context, CGRectGetMidX(rect), CGRectGetMaxY(rect));//左下if ((radiusflag & FS_DRAW_REGION_LEFT_BOTTOM_RADIUS) == FS_DRAW_REGION_LEFT_BOTTOM_RADIUS) {#ifdef MYDEBUGNSLog(@"FS_DRAW_REGION_LEFT_BOTTOM_RADIUS");#endifCGContextAddArcToPoint(context, CGRectGetMinX(rect), CGRectGetMaxY(rect), CGRectGetMinX(rect), CGRectGetMidY(rect), radius);} else {CGContextAddLineToPoint(context, CGRectGetMinX(rect), CGRectGetMaxY(rect));}CGContextAddLineToPoint(context, CGRectGetMinX(rect), CGRectGetMidY(rect));if (radiusflag == FS_DRAW_REGION_ROUND_RECT) {CGContextClosePath(context);}}}void drawLightForPath(CGContextRef context, CGRect rect, NSUInteger lightFlag, CGGradientRef gradient, CGFloat startRadius, CGFloat endRadius) {CGPoint startPoint = CGPointZero;CGPoint endPoint = CGPointZero;if (lightFlag == FS_LIGHT_FROM_INNER_TO_OUTER ||lightFlag == FS_LIGHT_FROM_OUTER_TO_INNER) {CGFloat radius1 = 0;CGFloat radius2 = 0;startPoint = CGPointMake(CGRectGetMinX(rect) + rect.size.width / 2.0f, CGRectGetMinY(rect) + rect.size.height / 2.0f);endPoint = startPoint;if (lightFlag == FS_LIGHT_FROM_INNER_TO_OUTER) {radius1 = MIN(startRadius, endRadius);radius2 = MAX(startRadius, endRadius);} else {radius1 = MAX(startRadius, endRadius);radius2 = MIN(startRadius, endRadius);}CGContextDrawRadialGradient(context, gradient, startPoint, radius1, endPoint, radius2, 0);} else {if (lightFlag == FS_LIGHT_FROM_TOP_TO_BOTTOM) {startPoint = CGPointMake(CGRectGetMidX(rect), CGRectGetMinY(rect));endPoint = CGPointMake(CGRectGetMidX(rect), CGRectGetMaxY(rect));} else if (lightFlag == FS_LIGHT_FROM_LEFT_TO_RIGHT) {startPoint = CGPointMake(CGRectGetMinX(rect), CGRectGetMidY(rect));endPoint = CGPointMake(CGRectGetMaxX(rect), CGRectGetMidY(rect));} else if (lightFlag == FS_DRAW_REGION_LEFT_BOTTOM_RADIUS) {startPoint = CGPointMake(CGRectGetMidX(rect), CGRectGetMaxY(rect));endPoint = CGPointMake(CGRectGetMidX(rect), CGRectGetMinY(rect));} else if (lightFlag == FS_LIGHT_FROM_RIGHT_TO_LEFT) {startPoint = CGPointMake(CGRectGetMaxX(rect), CGRectGetMidY(rect));endPoint = CGPointMake(CGRectGetMinX(rect), CGRectGetMidY(rect));} CGContextDrawLinearGradient(context, gradient, startPoint, endPoint, 0);}}void drawCrystalRect(CGContextRef context, CGRect rect, CGFloat radius, const CGFloat *components, NSUInteger componentCount) {//STEP 1.CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();//STEP 2.CGFloat colors[4] = {0};if (componentCount >= 4) {colors[0] = components[0];colors[1] = components[1];colors[2] = components[2];colors[3] = components[3];} else if (componentCount == 2) {colors[0] = components[0];colors[1] = components[0];colors[2] = components[0];colors[3] = components[1];}#ifdef MYDEBUGNSLog(@"componentCount=%d;r=%f;g=%f;b=%f;a=%f", componentCount, colors[0], colors[1], colors[2], colors[3]);#endifCGRect rClient = rect;rClient.origin.x++;rClient.origin.y++;rClient.size.width -= 2;rClient.size.height -= 2;CGContextSaveGState(context);buildPathForRect(context, rClient, radius, (FS_DRAW_REGION_LEFT_TOP_RADIUS | FS_DRAW_REGION_RIGHT_TOP_RADIUS | FS_DRAW_REGION_RIGHT_BOTTOM_RADIUS | FS_DRAW_REGION_LEFT_BOTTOM_RADIUS));CGContextSetRGBFillColor(context, colors[0], colors[1], colors[2], colors[3]);CGContextSetRGBStrokeColor(context, colors[0], colors[1], colors[2], colors[3]);CGContextSetLineWidth(context, 2.0f);CGContextDrawPath(context, kCGPathFillStroke);CGContextRestoreGState(context);//STEP 3.CGContextSaveGState(context);CGContextSetLineWidth(context, 2.0f);CGFloat topGradientColors[] = {1.0f, 1.0f, 1.0f, 0.6,1.0f, 1.0f, 1.0f, 0.3,1.0f, 1.0f, 1.0f, 0.0};CGRect topRect = CGRectMake(CGRectGetMinX(rClient), CGRectGetMinY(rClient), rClient.size.width, rClient.size.height / 2.0f);CGGradientRef topGradient = CGGradientCreateWithColorComponents(colorSpace, topGradientColors, NULL, sizeof(topGradientColors) / (4 * sizeof(CGFloat)));buildPathForRect(context, topRect, radius, (FS_DRAW_REGION_LEFT_TOP_RADIUS | FS_DRAW_REGION_RIGHT_TOP_RADIUS));CGContextClip(context);drawLightForPath(context, topRect, FS_LIGHT_FROM_TOP_TO_BOTTOM, topGradient, 0.0f, 0.0f);CGGradientRelease(topGradient);CGContextRestoreGState(context);//STEP 4.CGContextSaveGState(context);CGContextSetLineWidth(context, 2.0f);CGFloat bottomGradientColors[] = {0.0f, 0.0f, 0.0f, 0.15,0.0f, 0.0f, 0.0f, 0.15,0.0f, 0.0f, 0.0f, 0.15};CGRect bottomRect = CGRectMake(CGRectGetMinX(rClient), CGRectGetMidY(rClient), rClient.size.width, rClient.size.height / 2.0f);CGGradientRef bottomGradient = CGGradientCreateWithColorComponents(colorSpace, bottomGradientColors, NULL, sizeof(bottomGradientColors) / (4 * sizeof(CGFloat)));buildPathForRect(context, bottomRect, radius, FS_DRAW_REGION_RIGHT_BOTTOM_RADIUS | FS_DRAW_REGION_LEFT_BOTTOM_RADIUS);CGContextClip(context);drawLightForPath(context, bottomRect, FS_LIGHT_FROM_TOP_TO_BOTTOM, bottomGradient, 0.0f, 0.0f);CGGradientRelease(bottomGradient);CGContextRestoreGState(context);//STEP 5.rect.origin.x += 0.5;rect.origin.y += 0.5;rect.size.width -= 1;rect.size.height -= 1;CGContextSaveGState(context);buildPathForRect(context, rect, radius, (FS_DRAW_REGION_LEFT_TOP_RADIUS | FS_DRAW_REGION_RIGHT_TOP_RADIUS | FS_DRAW_REGION_RIGHT_BOTTOM_RADIUS | FS_DRAW_REGION_LEFT_BOTTOM_RADIUS));colors[0] += RGB_ADDTION * 1.2;colors[1] += RGB_ADDTION * 1.2;colors[2] += RGB_ADDTION * 1.2;if (colors[0] > 1) {colors[0] = 1.0f;}if (colors[1] > 1) {colors[1] = 1.0f;}if (colors[2] > 1) {colors[2] = 1.0f;}//CGContextSetRGBStrokeColor(context, 125.0f / 255.0f, 125.0f / 255.0f, 125.0f / 255.0f, 1.0f);CGContextSetRGBStrokeColor(context, colors[0], colors[1], colors[2], 1.0f);CGContextSetLineWidth(context, 1);CGContextDrawPath(context, kCGPathStroke);CGContextRestoreGState(context);//STEP 6.CGContextSaveGState(context);rect.origin.x += 1;rect.origin.y += 1;rect.size.width -= 2;rect.size.height -= 2;radius--;colors[0] -= RGB_ADDTION * 1.5f;colors[1] -= RGB_ADDTION * 1.5f;colors[2] -= RGB_ADDTION * 1.5f;if (colors[0] < 0) {colors[0] = 0.0f;}if (colors[1] < 0) {colors[1] = 0.0f;}if (colors[2] < 0) {colors[2] = 0.0f;}buildPathForRect(context, rect, radius, (FS_DRAW_REGION_LEFT_TOP_RADIUS | FS_DRAW_REGION_RIGHT_TOP_RADIUS | FS_DRAW_REGION_RIGHT_BOTTOM_RADIUS | FS_DRAW_REGION_LEFT_BOTTOM_RADIUS));//CGContextSetRGBStrokeColor(context, 229.0f / 255.0f, 229.0f / 255.0f, 229.0f / 255.0f, 1.0f);CGContextSetRGBStrokeColor(context, colors[0], colors[1], colors[2], 1.0f);CGContextSetLineWidth(context, 1.5);CGContextDrawPath(context, kCGPathStroke);CGContextRestoreGState(context);//STEP 7.CGColorSpaceRelease(colorSpace);}UIImage *createImageWithRect(CGRect rect, CGFloat radius, const CGFloat *components, NSUInteger componentCount) {UIImage *result = nil;//STEP 1.CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();CGContextRef context = CGBitmapContextCreate(NULL, rect.size.width, rect.size.height, 8, 0, colorSpace, kCGImageAlphaPremultipliedLast | kCGBitmapByteOrder32Little);CGContextTranslateCTM (context, 0, rect.size.height);CGContextScaleCTM(context, 1.0, -1.0);//STEP 2.drawCrystalRect(context, CGRectMake(0.0f, 0.0f, rect.size.width, rect.size.height), radius, components, componentCount);//STEP 3.CGImageRef image = CGBitmapContextCreateImage(context);result = [UIImage imageWithCGImage:image];CGImageRelease(image);CGContextRelease(context);CGColorSpaceRelease(colorSpace);//STEP 4.return result;}///////////////////////////////////////////绘制导航箭头////////////////////////////////////////void drawNavigatorArrow(CGContextRef context, CGRect rect, NSUInteger arrowDirection, const CGFloat *components, NSUInteger componentCount) {CGFloat colors[4] = {0};if (componentCount >= 4) {colors[0] = components[0];colors[1] = components[1];colors[2] = components[2];colors[3] = components[3];} else if (componentCount == 2) {colors[0] = components[0];colors[1] = components[0];colors[2] = components[0];colors[3] = components[1];} else {colors[0] = 239.0f / 255.0f;colors[1] = 239.0f / 255.0f;colors[2] = 239.0f / 255.0f;colors[3] = 1.0f;}//STEP 1.CGContextSaveGState(context);CGContextSetRGBStrokeColor(context, 1.0f, 1.0f, 1.0f, 0.0f);CGContextSetRGBFillColor(context, 1.0f, 1.0f, 1.0f, 0.0f);CGContextSetLineWidth(context, 0.0f);buildPathForRect(context, rect, 0.0f, FS_DRAW_REGION_RECT);CGContextDrawPath(context, kCGPathFillStroke);CGContextRestoreGState(context);//STEP 2.CGContextSaveGState(context);if (arrowDirection == FS_ARROW_UP) {CGContextMoveToPoint(context, CGRectGetMidX(rect), CGRectGetMinY(rect));CGContextAddLineToPoint(context, CGRectGetMaxX(rect), CGRectGetMidY(rect));CGContextAddLineToPoint(context, rect.size.width * 2 / 3.0f + CGRectGetMinX(rect), CGRectGetMidY(rect));CGContextAddLineToPoint(context, rect.size.width * 2 / 3.0f + CGRectGetMinX(rect), CGRectGetMaxY(rect));CGContextAddLineToPoint(context, rect.size.width / 3.0f + CGRectGetMinX(rect), CGRectGetMaxY(rect));CGContextAddLineToPoint(context, rect.size.width / 3.0f + CGRectGetMinX(rect), CGRectGetMidY(rect));CGContextAddLineToPoint(context, CGRectGetMinX(rect), CGRectGetMidY(rect));CGContextClosePath(context);} else if (arrowDirection == FS_ARROW_DOWN) {CGContextMoveToPoint(context, CGRectGetMidX(rect), CGRectGetMaxY(rect));CGContextAddLineToPoint(context, CGRectGetMaxX(rect), CGRectGetMidY(rect));CGContextAddLineToPoint(context, rect.size.width * 2 / 3.0f + CGRectGetMinX(rect), CGRectGetMidY(rect));CGContextAddLineToPoint(context, rect.size.width * 2 / 3.0f + CGRectGetMinX(rect), CGRectGetMinY(rect));CGContextAddLineToPoint(context, rect.size.width / 3.0f + CGRectGetMinX(rect), CGRectGetMinY(rect));CGContextAddLineToPoint(context, rect.size.width / 3.0f + CGRectGetMinX(rect), CGRectGetMidY(rect));CGContextAddLineToPoint(context, CGRectGetMinX(rect), CGRectGetMidY(rect));CGContextClosePath(context);} else if (arrowDirection == FS_ARROW_LEFT) {CGContextMoveToPoint(context, CGRectGetMinX(rect), CGRectGetMidY(rect));CGContextAddLineToPoint(context, CGRectGetMidX(rect), CGRectGetMinY(rect));CGContextAddLineToPoint(context, CGRectGetMidX(rect), rect.size.height / 3.0f + CGRectGetMinY(rect));CGContextAddLineToPoint(context, CGRectGetMaxX(rect), rect.size.height / 3.0f + CGRectGetMinY(rect));CGContextAddLineToPoint(context, CGRectGetMaxX(rect), rect.size.height * 2.0 / 3.0f + CGRectGetMinY(rect));CGContextAddLineToPoint(context, CGRectGetMidX(rect), rect.size.height * 2.0 / 3.0f + CGRectGetMinY(rect));CGContextAddLineToPoint(context, CGRectGetMidX(rect), CGRectGetMaxY(rect));CGContextClosePath(context);} else if (arrowDirection == FS_ARROW_RIGHT) {CGContextMoveToPoint(context, CGRectGetMaxX(rect), CGRectGetMidY(rect));CGContextAddLineToPoint(context, CGRectGetMidX(rect), CGRectGetMaxY(rect));CGContextAddLineToPoint(context, CGRectGetMidX(rect), rect.size.height * 2.0 / 3.0f + CGRectGetMinY(rect));CGContextAddLineToPoint(context, CGRectGetMinX(rect), rect.size.height * 2.0 / 3.0f + CGRectGetMinY(rect));CGContextAddLineToPoint(context, CGRectGetMinX(rect), rect.size.height / 3.0f + CGRectGetMinY(rect));CGContextAddLineToPoint(context, CGRectGetMidX(rect), rect.size.height / 3.0f + CGRectGetMinY(rect));CGContextAddLineToPoint(context, CGRectGetMidX(rect), CGRectGetMinY(rect));CGContextClosePath(context);} else {CGContextMoveToPoint(context, CGRectGetMinX(rect), CGRectGetMidY(rect));CGContextAddLineToPoint(context, CGRectGetMidX(rect), CGRectGetMinY(rect));CGContextAddLineToPoint(context, CGRectGetMidX(rect), rect.size.height / 3.0f + CGRectGetMinY(rect));CGContextAddLineToPoint(context, CGRectGetMaxX(rect), rect.size.height / 3.0f + CGRectGetMinY(rect));CGContextAddLineToPoint(context, CGRectGetMaxX(rect), rect.size.height * 2.0 / 3.0f + CGRectGetMinY(rect));CGContextAddLineToPoint(context, CGRectGetMidX(rect), rect.size.height * 2.0 / 3.0f + CGRectGetMinY(rect));CGContextAddLineToPoint(context, CGRectGetMidX(rect), CGRectGetMaxY(rect));CGContextClosePath(context);}CGContextSetRGBFillColor(context, colors[0], colors[1], colors[2], colors[3]);CGContextSetRGBStrokeColor(context, colors[0], colors[1], colors[2], colors[3]);CGContextSetLineWidth(context, 1.0f);CGContextDrawPath(context, kCGPathFillStroke);CGContextRestoreGState(context);}UIImage *createNavigatorArrowWithRect(CGRect rect, NSUInteger arrowDirection, CGFloat boundSpace, const CGFloat *components, NSUInteger componentCount) {UIImage *result = nil;//STEP 1.CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();CGContextRef context = CGBitmapContextCreate(NULL, rect.size.width, rect.size.height, 8, 0, colorSpace, kCGImageAlphaPremultipliedLast | kCGBitmapByteOrder32Little);CGContextTranslateCTM (context, 0, rect.size.height);CGContextScaleCTM(context, 1.0, -1.0);//STEP 2.CGRect rArrow = CGRectMake(boundSpace + CGRectGetMinX(rect), boundSpace + CGRectGetMinY(rect), rect.size.width - boundSpace * 2.0f, rect.size.height - boundSpace * 2.0f);drawNavigatorArrow(context, rArrow, arrowDirection, components, componentCount);//STEP 3.CGImageRef image = CGBitmapContextCreateImage(context);result = [UIImage imageWithCGImage:image];CGImageRelease(image);CGContextRelease(context);CGColorSpaceRelease(colorSpace);//STEP 4.return result;}UIImage *scaleImage(UIImage *source, CGSize destSize) {CGFloat destW = destSize.width;CGFloat destH = destSize.height;CGImageRef imageRef = source.CGImage;CGBitmapInfo bitmapInfo = kCGBitmapByteOrder32Little | kCGImageAlphaPremultipliedLast;//CGImageGetBitmapInfo(imageRef);CGColorSpaceRef colorSpaceInfo = CGImageGetColorSpace(imageRef);CGContextRef bitmap = NULL;size_t bitsPerComponent = CGImageGetBitsPerComponent(imageRef);size_t bytesPerRow = 0;// CGImageGetBytesPerRow(imageRef);#ifdef MYDEBUGNSLog(@"bitsPerComponent=%d;bytesPerRow=%d", bitsPerComponent, bytesPerRow);#endifif (source.imageOrientation == UIImageOrientationUp || source.imageOrientation == UIImageOrientationDown) {bitmap = CGBitmapContextCreate(NULL, destW, destH, bitsPerComponent, bytesPerRow, colorSpaceInfo, bitmapInfo);} else {bitmap = CGBitmapContextCreate(NULL, destH, destW, bitsPerComponent, bytesPerRow, colorSpaceInfo, bitmapInfo);}if (source.imageOrientation == UIImageOrientationLeft) {CGContextRotateCTM (bitmap, M_PI / 2.0f);CGContextTranslateCTM (bitmap, 0, - destW);} else if (source.imageOrientation == UIImageOrientationRight) {CGContextRotateCTM (bitmap, - M_PI / 2.0f);CGContextTranslateCTM (bitmap, - destW, 0);} else if (source.imageOrientation == UIImageOrientationUp) {// NOTHING} else if (source.imageOrientation == UIImageOrientationDown) {CGContextTranslateCTM (bitmap, destW, destH);CGContextRotateCTM (bitmap, - M_PI);}//CGContextScaleCTM(bitmap, destW / source.size.width, destH / source.size.height);CGContextDrawImage(bitmap, CGRectMake(0, 0, destW, destH), imageRef);CGImageRef ref = CGBitmapContextCreateImage(bitmap);UIImage *result = [UIImage imageWithCGImage:ref];CGContextRelease(bitmap);CGImageRelease(ref);return result;}void drawImageWithRect(CGContextRef context, CGRect rect, UIImage *image) {NSInteger colCount = rect.size.width / image.size.width + 1;NSInteger rowCount = rect.size.height / image.size.height + 1;CGFloat left = CGRectGetMinX(rect);CGFloat top = CGRectGetMinY(rect);for (int i = 0; i < rowCount; i++) {for (int j = 0; j < colCount; j++) {CGRect rImage = CGRectMake(left, top, image.size.width, image.size.height);CGContextDrawImage(context, rImage, image.CGImage);left += rImage.size.width;}top += image.size.height;left = CGRectGetMinX(rect);//top += 100;}}UIImage *drawImageAndTextInRect(CGRect rect, UIImage *source, NSString *text, NSInteger textAlign) {UIImage *result = nil;CGFloat radius = 4.0f;CGFloat components[] = {184.0f / 255.0f,235.0f / 255.0f,255.0f / 255.0f,1.0f};NSInteger componentCount = sizeof(components) / sizeof(CGFloat);//STEP 1.CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();CGContextRef context = CGBitmapContextCreate(NULL, rect.size.width, rect.size.height, 8, 0, colorSpace, kCGImageAlphaPremultipliedLast | kCGBitmapByteOrder32Little);CGContextTranslateCTM (context, 0, rect.size.height);CGContextScaleCTM(context, 1.0, -1.0);//STEP 2.drawCrystalRect(context, CGRectMake(0.0f, 0.0f, rect.size.width, rect.size.height), radius, components, componentCount);//STEP 3.文字//STEP 3.CGImageRef image = CGBitmapContextCreateImage(context);result = [UIImage imageWithCGImage:image];CGImageRelease(image);CGContextRelease(context);CGColorSpaceRelease(colorSpace);//STEP 4.return result;}UIImage *createImageInRectWithGradient(CGRect rect, CGFloat radius, const CGFloat *components, NSUInteger componentCount, CGFloat borderWidth) {UIImage *result = nil;//STEP 1.CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();CGContextRef context = CGBitmapContextCreate(NULL, rect.size.width, rect.size.height, 8, 0, colorSpace, kCGImageAlphaPremultipliedLast | kCGBitmapByteOrder32Little);CGContextTranslateCTM (context, 0, rect.size.height);CGContextScaleCTM(context, 1.0, -1.0);//STEP 2.drawGradientInRectWithSingleColor(rect, radius, borderWidth, context, colorSpace, components, componentCount, GRADIENT_RECT_FROM_TOP_TO_BOTTOM);//STEP 3.CGImageRef image = CGBitmapContextCreateImage(context);result = [UIImage imageWithCGImage:image];CGImageRelease(image);CGContextRelease(context);CGColorSpaceRelease(colorSpace);//STEP 4.return result;}//在一个矩形内部进行绘制渐变void drawGradientInRect(CGRect rect, CGContextRef context, CGColorSpaceRef colorSpace, const CGFloat *components, NSUInteger componentCount, NSUInteger directFlag) {CGGradientRef gradient = CGGradientCreateWithColorComponents(colorSpace, components, NULL, componentCount / 4);CGPoint startPoint = CGPointZero;CGPoint endPoint = CGPointZero;if (directFlag == GRADIENT_RECT_FROM_TOP_TO_BOTTOM) {startPoint = CGPointMake(CGRectGetMidX(rect), CGRectGetMinY(rect));endPoint = CGPointMake(CGRectGetMidX(rect), CGRectGetMaxY(rect));} else if (directFlag == GRADIENT_RECT_FROM_BOTTOM_TO_TOP) {endPoint = CGPointMake(CGRectGetMidX(rect), CGRectGetMinY(rect));startPoint = CGPointMake(CGRectGetMidX(rect), CGRectGetMaxY(rect));} else if (directFlag == GRADIENT_RECT_FROM_LEFT_TO_RIGHT) {startPoint = CGPointMake(CGRectGetMinX(rect), CGRectGetMidY(rect));endPoint = CGPointMake(CGRectGetMaxX(rect), CGRectGetMidY(rect));} else if (directFlag == GRADIENT_RECT_FROM_RIGHT_TO_LEFT) {endPoint = CGPointMake(CGRectGetMinX(rect), CGRectGetMidY(rect));startPoint = CGPointMake(CGRectGetMaxX(rect), CGRectGetMidY(rect));} else {startPoint = CGPointMake(CGRectGetMinX(rect), CGRectGetMidY(rect));endPoint = CGPointMake(CGRectGetMaxX(rect), CGRectGetMidY(rect));}CGContextDrawLinearGradient(context, gradient, startPoint, endPoint, 0);CGGradientRelease(gradient);}void drawTopGradientInRect(CGRect rect, CGContextRef context, CGColorSpaceRef colorSpace) {CGFloat colorTop[] ={//239.0f / 255.0f, 239.0f / 255.0f, 239.0f / 255.0f, 0.35f,239.0f / 255.0f, 239.0f / 255.0f, 239.0f / 255.0f, 0.40f,//239.0f / 255.0f, 239.0f / 255.0f, 239.0f / 255.0f, 0.25f,239.0f / 255.0f, 239.0f / 255.0f, 239.0f / 255.0f, 0.20f,//239.0f / 255.0f, 239.0f / 255.0f, 239.0f / 255.0f, 0.15f,239.0f / 255.0f, 239.0f / 255.0f, 239.0f / 255.0f, 0.10f,239.0f / 255.0f, 239.0f / 255.0f, 239.0f / 255.0f, 0.05f,239.0f / 255.0f, 239.0f / 255.0f, 239.0f / 255.0f, 0.0f,};drawGradientInRect(rect, context, colorSpace, colorTop, sizeof(colorTop) / sizeof(CGFloat), GRADIENT_RECT_FROM_TOP_TO_BOTTOM);}void drawBottomGradientInRect(CGRect rect, CGContextRef context, CGColorSpaceRef colorSpace) {CGFloat colorBottom[] = {//5.0f / 255.0f, 5.0f / 255.0f, 5.0f / 255.0f, 0.05f,//5.0f / 255.0f, 5.0f / 255.0f, 5.0f / 255.0f, 0.20f,5.0f / 255.0f, 5.0f / 255.0f, 5.0f / 255.0f, 0.15f,5.0f / 255.0f, 5.0f / 255.0f, 5.0f / 255.0f, 0.25f,5.0f / 255.0f, 5.0f / 255.0f, 5.0f / 255.0f, 0.35f,5.0f / 255.0f, 5.0f / 255.0f, 5.0f / 255.0f, 0.45f,//5.0f / 255.0f, 5.0f / 255.0f, 5.0f / 255.0f, 0.0f,};drawGradientInRect(rect, context, colorSpace, colorBottom, sizeof(colorBottom) / sizeof(CGFloat), GRADIENT_RECT_FROM_TOP_TO_BOTTOM);}void drawGradientInRectWithSingleColor(CGRect rect, CGFloat radius, CGFloat borderWidth, CGContextRef context, CGColorSpaceRef colorSpace, const CGFloat *components, NSUInteger componentCount, NSUInteger directFlag) {CGFloat borderWidth_Real = borderWidth;if (borderWidth_Real >= 0.0f) {borderWidth_Real = 1.0f;}CGFloat colors[4] = {0};if (componentCount >= 4) {colors[0] = components[0];colors[1] = components[1];colors[2] = components[2];colors[3] = components[3];} else if (componentCount == 2) {colors[0] = components[0];colors[1] = components[0];colors[2] = components[0];colors[3] = components[1];}CGRect rClient = rect;CGFloat boundsSpace = 1.0f;rClient.origin.x += (borderWidth_Real / 2.0f + boundsSpace);rClient.origin.y += (borderWidth_Real / 2.0f + boundsSpace); rClient.size.width -= (borderWidth_Real + boundsSpace * 2.0f);rClient.size.height -= (borderWidth_Real + boundsSpace * 2.0f);//STEP 1.CGContextSaveGState(context);CGContextSetRGBFillColor(context, colors[0], colors[1], colors[2], colors[3]);CGContextSetRGBStrokeColor(context, colors[0], colors[1], colors[3], colors[3]);buildPathForRect(context, rClient, radius, FS_DRAW_REGION_ROUND_RECT);UIColor *shadowColor = [[UIColor alloc] initWithRed:colors[0] green:colors[1] blue:colors[2] alpha:colors[3]];CGContextSetShadowWithColor(context, CGSizeMake(-1.0f, 1.0f), 2.0f, shadowColor.CGColor);[shadowColor release];CGContextSetLineWidth(context, 0.0f);CGContextDrawPath(context, kCGPathFillStroke);CGContextRestoreGState(context);//STEP 2.CGContextSaveGState(context);CGFloat gradientColors[] = {1.0f, 1.0f, 1.0f, 0.75f,1.0f, 1.0f, 1.0f, 0.55f,1.0f, 1.0f, 1.0f, 0.25f,1.0f, 1.0f, 1.0f, 0.0f,};CGGradientRef gradient = CGGradientCreateWithColorComponents(colorSpace, gradientColors, NULL, sizeof(gradientColors)/ (4 * sizeof(CGFloat)));buildPathForRect(context, rClient, radius, FS_DRAW_REGION_ROUND_RECT);CGContextClip(context);CGPoint startPoint = CGPointZero;CGPoint endPoint = CGPointZero;if (directFlag == GRADIENT_RECT_FROM_TOP_TO_BOTTOM) {startPoint = CGPointMake(CGRectGetMidX(rClient), CGRectGetMinY(rClient));endPoint = CGPointMake(CGRectGetMidX(rClient), CGRectGetMaxY(rClient));} else if (directFlag == GRADIENT_RECT_FROM_BOTTOM_TO_TOP) {endPoint = CGPointMake(CGRectGetMidX(rClient), CGRectGetMinY(rClient));startPoint = CGPointMake(CGRectGetMidX(rClient), CGRectGetMaxY(rClient));} else if (directFlag == GRADIENT_RECT_FROM_LEFT_TO_RIGHT) {startPoint = CGPointMake(CGRectGetMinX(rClient), CGRectGetMidY(rClient));endPoint = CGPointMake(CGRectGetMaxX(rClient), CGRectGetMidY(rClient));} else if (directFlag == GRADIENT_RECT_FROM_RIGHT_TO_LEFT) {endPoint = CGPointMake(CGRectGetMinX(rClient), CGRectGetMidY(rClient));startPoint = CGPointMake(CGRectGetMaxX(rClient), CGRectGetMidY(rClient));} else {startPoint = CGPointMake(CGRectGetMinX(rClient), CGRectGetMidY(rClient));endPoint = CGPointMake(CGRectGetMaxX(rClient), CGRectGetMidY(rClient));}CGContextDrawLinearGradient(context, gradient, startPoint, endPoint, 0);CGGradientRelease(gradient);CGContextRestoreGState(context);}

使用方法：

UIColor *btnBGColor = [[UIColor alloc] initWithRed:0.0f / 255.0f green:132.0f / 255.0f blue:189.0f / 255.0f alpha:1.0f];UIImage *bgImage = createImageWithRect(CGRectMake(0.0f, 0.0f, SNSLOGIN_BUTTON_WIDTH, SNSLOGIN_BUTTON_HEIGHT), SNSLOGIN_BUTTON_RADIUS, CGColorGetComponents(btnBGColor.CGColor), CGColorGetNumberOfComponents(btnBGColor.CGColor));[btnBGColor release];_btnLogin = [[UIButton alloc] initWithFrame:CGRectZero];[_btnLogin setTitle:@"登录" forState:UIControlStateNormal];[_btnLogin setBackgroundImage:bgImage forState:UIControlStateNormal];[_btnLogin.titleLabel setFont:[UIFont boldSystemFontOfSize:18.0f]];[_btnLogin addTarget:self action:@selector(loginAction:) forControlEvents:UIControlEventTouchUpInside];[self addSubview:_btnLogin];

示例图片：