问题
I am making a simple program that creates game cards for a game I play. I have sent it out to some friends of mine for testing, but they really want it to save images, not just print them. I have tried to make it save as a .png file. I have to questions here.
How can I make it save my view as a .png file, including all of the view's NSImageWells.
How can I add an NSPopupButton to an NSSavePanel to allow users to select a format?
Any help is greatly appreciated.
回答1:
First create a TIFF representation of your view:
// Get the data into a bitmap.
[self lockFocus];
rep = [[NSBitmapImageRep alloc] initWithFocusedViewRect:[self bounds]];
[self unlockFocus];
data = [rep TIFFRepresentation];
To support multiple file types, use:
data = [rep representationUsingType:(NSBitmapImageFileType)storageType
properties:(NSDictionary *)properties];
NSBitmapImageFileType is an enum constant specifying a file type for bitmap images. It can be NSBMPFileType, NSGIFFileType, NSJPEGFileType, NSPNGFileType, or NSTIFFFileType.
If you need to customize the NSSavePanel, look into accessory views: http://developer.apple.com/library/mac/#documentation/Cocoa/Conceptual/AppFileMgmt/Articles/ManagingAccessoryViews.html
回答2:
// Get the data into a bitmap.
[viewBarChart lockFocus];
NSBitmapImageRep *rep = [[NSBitmapImageRep alloc] initWithFocusedViewRect:[viewBarChart bounds]];
[viewBarChart unlockFocus];
NSData *exportedData = [rep representationUsingType:NSJPEGFileType properties:nil];
NSSavePanel *savepanel = [NSSavePanel savePanel];
savepanel.title = @"Save chart";
[savepanel setAllowedFileTypes:[NSArray arrayWithObject:@"jpg"]];
[savepanel beginSheetModalForWindow:self.view.window completionHandler:^(NSInteger result)
{
if (NSFileHandlingPanelOKButton == result)
{
NSURL* fileURL = [savepanel URL];
if ([fileURL.pathExtension isEqualToString:@""])
fileURL = [fileURL URLByAppendingPathExtension:@"jpg"];
[exportedData writeToURL:fileURL atomically:YES];
}
[rep release];
}];
来源:https://stackoverflow.com/questions/5491403/saving-an-nsview-to-a-png-file