Question

我需要截取整个屏幕的截图，包括状态栏，我使用CARenderServerRenderDisplay来实现这一点，它可以在iPad上正常工作，但在iPhone 6 Plus上却出错了。作为代码中*标记的部分，如果我设置width=screenSize.width*scale和height=screenSize.height*scale，则会导致崩溃，如果我只是将它们更改为：width=screenSize.height*scale和height=screenSize.width*scale，它将会工作，但产生这样的图像：，我已经尝试了很多，但没有找到理由，有人知道吗？我希望我已经足够清楚地描述了它。

- (void)snapshot
{
    CGFloat scale = [UIScreen mainScreen].scale;
    CGSize screenSize = [UIScreen mainScreen].bounds.size;

    //*********** the place where problem appears        
    size_t width = screenSize.height * scale;
    size_t height = screenSize.width * scale;
    //***********

    size_t bytesPerElement = 4;
    OSType pixelFormat = 'ARGB';
    size_t bytesPerRow = bytesPerElement * width;
    size_t surfaceAllocSize = bytesPerRow * height;

    NSDictionary *properties = [NSDictionary dictionaryWithObjectsAndKeys:
                                [NSNumber numberWithBool:YES], kIOSurfaceIsGlobal,
                                [NSNumber numberWithUnsignedLong:bytesPerElement], kIOSurfaceBytesPerElement,
                                [NSNumber numberWithUnsignedLong:bytesPerRow], kIOSurfaceBytesPerRow,
                                [NSNumber numberWithUnsignedLong:width], kIOSurfaceWidth,
                                [NSNumber numberWithUnsignedLong:height], kIOSurfaceHeight,
                                [NSNumber numberWithUnsignedInt:pixelFormat], kIOSurfacePixelFormat,
                                [NSNumber numberWithUnsignedLong:surfaceAllocSize], kIOSurfaceAllocSize,
                                nil];

    IOSurfaceRef destSurf = IOSurfaceCreate((__bridge CFDictionaryRef)(properties));

    IOSurfaceLock(destSurf, 0, NULL);
    CARenderServerRenderDisplay(0, CFSTR("LCD"), destSurf, 0, 0);
    IOSurfaceUnlock(destSurf, 0, NULL);

    CGDataProviderRef provider =  CGDataProviderCreateWithData(NULL, IOSurfaceGetBaseAddress(destSurf), (width * height * 4), NULL);
    CGImageRef cgImage = CGImageCreate(width, height, 8,
                                       8*4, IOSurfaceGetBytesPerRow(destSurf),
                                       CGColorSpaceCreateDeviceRGB(), kCGImageAlphaNoneSkipFirst |kCGBitmapByteOrder32Little,
                                       provider, NULL, YES, kCGRenderingIntentDefault);
    UIImage *image = [UIImage imageWithCGImage:cgImage];
    UIImageWriteToSavedPhotosAlbum(image, nil, nil, nil);
}

Answer 1

如果您使用的是越狱环境，则可以使用私人UIImage方法_UICreateScreenUIImage：

OBJC_EXTERN UIImage *_UICreateScreenUIImage(void);

// ...

- (void)takeScreenshot {
    UIImage *screenImage = _UICreateScreenUIImage();
    // do something with your screenshot
}

此方法使用CARenderServerRenderDisplay来更快地呈现整个设备屏幕。它取代了在arm64版本的iOS 7 SDK中删除的UICreateScreenImage和UIGetScreenImage方法。

如何在Jailbroken iOS设备上截取整个屏幕的截图？

1 个答案: