Sunday, June 16, 2013

NSFileWrapper addRegularFileWithContents example in Objective C (iOS).

NSFileWrapper addRegularFileWithContents

Creates a regular-file file wrapper with the given contents and adds it to the receiver, which must be a directory file wrapper.

- (NSString *)addRegularFileWithContents:(NSData *)data preferredFilename:(NSString *)filename

Contents for the new regular-file file wrapper.
Preferred filename for the new regular-file file wrapper.

Return Value of [NSFileWrapper addRegularFileWithContents]
Dictionary key used to store the new file wrapper in the directory’s list of file wrappers. The dictionary key is a unique filename, which is the same as the passed-in file wrapper's preferred filename unless that name is already in use as a key in the directory's dictionary of children. See “Working With Directory Wrappers” in Application File Management for more information about the file-wrapper list structure.

Discussion of [NSFileWrapper addRegularFileWithContents]
This is a convenience method. The default implementation allocates a new file wrapper, initializes it with initRegularFileWithContents:, sends it setPreferredFilename:, adds it to the directory with addFileWrapper:, and returns what addFileWrapper: returned.

Special Considerations
This method raises NSInternalInconsistencyException if the receiver is not a directory file wrapper.

This method raises NSInvalidArgumentException if you pass nil or an empty value for filename.

NSFileWrapper addRegularFileWithContents example.
- (BOOL)readFromFileWrapper:(NSFileWrapper *)dirWrapper
                     ofType:(NSString *)typeName
                      error:(NSError **)outError

    NSFileWrapper *wrapper;
    NSData *data;

    wrapper = [[dirWrapper fileWrappers] objectForKey:@"MainDocument.pdf"];
    data = [wrapper regularFileContents];
    self.pdfData = data;

    wrapper = [[dirWrapper fileWrappers] objectForKey:@"SignatureBitmap.png"];
    data = [wrapper regularFileContents];
    self.signatureBitmapData = data;


    return YES;

- (NSFileWrapper *)fileWrapperOfType:(NSString *)typeName
                               error:(NSError **)outError
    NSFileWrapper *dirWrapper = [[[NSFileWrapper alloc]
        initDirectoryWithFileWrappers:nil] autorelease];

    [dirWrapper addRegularFileWithContents:self.pdfData

    [dirWrapper addRegularFileWithContents:self.signatureBitmapData


    return dirWrapper;

Example of [NSFileWrapper addRegularFileWithContents].
NSFileWrapper *oldFileWrapper = [self.fileWrapper.fileWrappers objectForKey:fileName];
if (oldFileWrapper) [self.fileWrapper removeFileWrapper:oldFileWrapper];

[self.fileWrapper addRegularFileWithContents:[self encodeObject:object]

NSFileWrapper addRegularFileWithContents example.
- (NSFileWrapper *)fileWrapperOfType:(NSString *)typeName error:(NSError **)outError
    NSFileWrapper *wrapper = [[[NSFileWrapper alloc] initDirectoryWithFileWrappers:nil] autorelease];
    [wrapper addRegularFileWithContents:[@"please work" dataUsingEncoding:NSUTF8StringEncoding] preferredFilename:@"foobar"];
    NSDictionary *metadata = [NSDictionary dictionaryWithObject:@"0.1" forKey:@"Version"];
    NSString* errorDescription = nil;
    NSData* dictionaryData = [NSPropertyListSerialization dataFromPropertyList:metadata format:NSPropertyListBinaryFormat_v1_0 errorDescription:&errorDescription];
            errorDescription = @"Unknown error";
            *outError = [NSError errorWithDomain:@"YourErrorDomain" code:69 userInfo:[NSDictionary dictionaryWithObject:errorDescription forKey:NSLocalizedDescriptionKey]];
        return nil;
    [wrapper addRegularFileWithContents:dictionaryData preferredFilename:@"Info.plist"];
    return wrapper;

End of NSFileWrapper addRegularFileWithContents example article.