方法一:
UIGraphicsBeginImageContextWithOptions(pageView.page.bounds.size, YES, zoomScale); [pageView.page.layer renderInContext:UIGraphicsGetCurrentContext()]; UIImage *uiImage = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext();
方法二:
- (UIImage *) glToUIImage { DWScrollView *pageView = [self getActivePageView]; pageView.page.backgroundColor = [UIColor clearColor]; // self.backgroundColor=[UIColor clearColor]; NSInteger myDataLength = 320 * 308 * 4; // allocate array and read pixels into it. GLubyte *buffer = (GLubyte *) malloc(myDataLength); glReadPixels(0, 0, 320, 308, GL_RGBA, GL_UNSIGNED_BYTE, buffer); // gl renders "upside down" so swap top to bottom into new array. // there's gotta be a better way, but this works. GLubyte *buffer2 = (GLubyte *) malloc(myDataLength); for(int y = 0; y <308; y++) { for(int x = 0; x <320 * 4; x++) { if(buffer[y* 4 * 320 + x]==0) buffer2[(307 - y) * 320 * 4 + x]=1; else buffer2[(307 - y) * 320 * 4 + x] = buffer[y* 4 * 320 + x]; } } // make data provider with data. CGDataProviderRef provider = CGDataProviderCreateWithData(NULL, buffer2, myDataLength, NULL); // prep the ingredients int bitsPerComponent = 8; int bitsPerPixel = 32; int bytesPerRow = 4 * 320; CGColorSpaceRef colorSpaceRef = CGColorSpaceCreateDeviceRGB(); CGBitmapInfo bitmapInfo = kCGBitmapByteOrderDefault; CGColorRenderingIntent renderingIntent = kCGRenderingIntentDefault; // make the cgimage CGImageRef imageRef = CGImageCreate(320, 308, bitsPerComponent, bitsPerPixel, bytesPerRow, colorSpaceRef, bitmapInfo, provider, NULL, NO, renderingIntent); // then make the uiimage from that UIImage *myImage = [UIImage imageWithCGImage:imageRef]; UIImageWriteToSavedPhotosAlbum(myImage, nil, nil, nil); return myImage; }
方法三:
// get screen - (void)grabScreen { unsigned char buffer[320*480*4]; glReadPixels(0,0,320,480,GL_RGBA,GL_UNSIGNED_BYTE,&buffer); CGDataProviderRef ref = CGDataProviderCreateWithData(NULL, &buffer, 320*480*4, NULL); CGImageRef iref = CGImageCreate(320,480,8,32,320*4,CGColorSpaceCreateDeviceRGB(),kCGBitmapByteOrderDefault,ref,NULL,true,kCGRenderingIntentDefault); CGFloat width = CGImageGetWidth(iref); CGFloat height = CGImageGetHeight(iref); size_t length = width*height*4; uint32_t *pixels = (uint32_t *)malloc(length); CGContextRef context = CGBitmapContextCreate(pixels, width, height, 8, 320*4, CGImageGetColorSpace(iref), kCGImageAlphaLast | kCGBitmapByteOrder32Big); CGContextTranslateCTM(context, 0.0, height); CGContextScaleCTM(context, 1.0, -1.0); CGContextDrawImage(context, CGRectMake(0.0, 0.0, width, height), iref); CGImageRef outputRef = CGBitmapContextCreateImage(context); UIImage *outputImage = [UIImage imageWithCGImage:outputRef]; UIImageWriteToSavedPhotosAlbum(outputImage, nil, nil, nil); CGContextRelease(context); CGImageRelease(iref); CGDataProviderRelease(ref); }
方法四:
CGImageRef UIGetScreenImage(); void SaveScreenImage(NSString *path) { NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init]; CGImageRef cgImage = UIGetScreenImage(); void *imageBytes = NULL; if (cgImage == NULL) { CGColorSpaceRef colorspace = CGColorSpaceCreateDeviceRGB(); imageBytes = malloc(320 * 480 * 4); CGContextRef context = CGBitmapContextCreate(imageBytes, 320, 480, 8, 320 * 4, colorspace, kCGImageAlphaNoneSkipFirst | kCGBitmapByteOrder32Big); CGColorSpaceRelease(colorspace); for (UIWindow *window in [[UIApplication sharedApplication] windows]) { CGRect bounds = [window bounds]; CALayer *layer = [window layer]; CGContextSaveGState(context); if ([layer contentsAreFlipped]) { CGContextTranslateCTM(context, 0.0f, bounds.size.height); CGContextScaleCTM(context, 1.0f, -1.0f); } [layer renderInContext:(CGContextRef)context]; CGContextRestoreGState(context); } cgImage = CGBitmapContextCreateImage(context); CGContextRelease(context); } NSData *pngData = UIImagePNGRepresentation([UIImage imageWithCGImage:cgImage]); CGImageRelease(cgImage); if (imageBytes) free(imageBytes); [pngData writeToFile:path atomically:YES]; [pool release]; }
方法五:
+ (UIImage *)imageWithScreenContents { CGImageRef cgScreen = UIGetScreenImage(); if (cgScreen) { UIImage *result = [UIImage imageWithCGImage:cgScreen]; CGImageRelease(cgScreen); return result; } return nil; }转自:http://www.cocoachina.com/newbie/basic/2011/1205/3664.html