Trying to read in an RTF file in Objective-C - objective-c

Question

I have an RTF file that I am reading in using a command line application in Objective-C. I'm using Dave DeLong's code from this question: How to read data from NSFileHandle line by line?
My problem is that my output is coming out like this:
2014-06-21 20:03:45.578 AjrumTest[5663:303] {\rtf1\ansi\ansicpg1252\cocoartf1265\cocoasubrtf200
2014-06-21 20:03:45.579 AjrumTest[5663:303] {\fonttbl\f0\fnil\fcharset0 LucidaGrande;\f1\fnil\fcharset178 AlBayan;\f2\froman\fcharset0 TimesNewRomanPSMT;
2014-06-21 20:03:45.580 AjrumTest[5663:303] \f3\fnil\fcharset178 GeezaPro;}
2014-06-21 20:03:45.580 AjrumTest[5663:303] {\colortbl;\red255\green255\blue255;}
2014-06-21 20:03:45.581 AjrumTest[5663:303] \margl1440\margr1440\vieww10800\viewh8400\viewkind0
2014-06-21 20:03:45.581 AjrumTest[5663:303] \deftab720
2014-06-21 20:03:45.581 AjrumTest[5663:303] \pard\pardeftab720
2014-06-21 20:03:45.582 AjrumTest[5663:303]
2014-06-21 20:03:45.582 AjrumTest[5663:303] \f0\fs46 \cf0 1
2014-06-21 20:03:45.582 AjrumTest[5663:303] \f1 - \'de\'f3\'dc\'c7\'e1\'f3 \'c7\'c8\'fa\'dc\'e4\'f5 \'c2\'c8\'f3\'f8 \'e6\'f3\'c7\'d3\'fa\'e3\'f5\'dc\'e5\'f5 \'e3\'f5\'cd\'f3\'e3\'f3\'f8\'dc\'cf\'f5
...
I realize that because the document I am reading in is an RTF file, that I need to attach the necessary attributes to it. I pass in my file from the main method like this:
NSString *pathToMyFile = [[NSBundle mainBundle] pathForResource:#"MyRTFDocument" ofType:#"rtf"];
DDFileReader * reader = [[DDFileReader alloc] initWithFilePath:pathToMyFile];
[reader enumerateLinesUsingBlock:^(NSString *line, BOOL *stop) {
NSLog(#"%#", line);
}];
Here is how the document is then parsed:
- (NSString *) readLine {
if (currentOffset >= totalFileLength) {
return nil;
}
NSData *newLineData = [lineDelimiter dataUsingEncoding:NSUTF8StringEncoding];
[fileHandle seekToFileOffset:currentOffset];
NSMutableData * currentData = [[NSMutableData alloc] init];
BOOL shouldReadMore = YES;
#autoreleasepool {
while (shouldReadMore) {
if (currentOffset >= totalFileLength) {
break;
}
NSData *chunk = [fileHandle readDataOfLength:chunkSize];
NSRange newLineRange = [chunk rangeOfData_dd:newLineData];
if (newLineRange.location != NSNotFound) {
//include the length so we can include the delimiter in the string
chunk = [chunk subdataWithRange:NSMakeRange(0, newLineRange.location+[newLineData length])];
shouldReadMore = NO;
}
[currentData appendData:chunk];
currentOffset += [chunk length];
}
}
NSDictionary *attrs = #{NSDocumentTypeDocumentAttribute: NSRTFTextDocumentType, NSWritingDirectionAttributeName:#[#(NSWritingDirectionRightToLeft | NSTextWritingDirectionOverride)]};
NSAttributedString *attrString = [[NSAttributedString alloc] initWithData:currentData options:attrs documentAttributes:nil error:nil];
//NSLog(#"What does this give me? %#", [attrString string]);
//The above line outputs (null) for [attrString string]
NSString *line = [[NSString alloc] initWithData:currentData encoding:NSUTF8StringEncoding];
return line;
}
- (NSString *) readTrimmedLine {
return [[self readLine] stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
}
#if NS_BLOCKS_AVAILABLE
- (void) enumerateLinesUsingBlock:(void(^)(NSString*, BOOL*))block {
NSString *line = nil;
BOOL stop = NO;
while (stop == NO && (line = [self readLine])) {
block(line, &stop);
}
}
#endif
When I attach the correct document attributes to the NSData object before creating an NSAttributedString, I get an object that is null:
NSDictionary *attrs = #{NSDocumentTypeDocumentAttribute: NSRTFTextDocumentType, NSWritingDirectionAttributeName:#[#(NSWritingDirectionRightToLeft | NSTextWritingDirectionOverride)]};
NSAttributedString *attrString = [[NSAttributedString alloc] initWithData:currentData options:attrs documentAttributes:nil error:nil];
NSLog(#"%#", [attrString string]);
In another iOS application, I have the following code which works exactly as I want:
NSString *path = [[NSBundle mainBundle] pathForResource:#"AjrumiyyahPoemRawTextRTF" ofType:#"rtf"];
NSData *testData = [NSData dataWithContentsOfFile:path];
NSDictionary *attrs = #{NSDocumentTypeDocumentAttribute: NSRTFTextDocumentType, NSWritingDirectionAttributeName:#[#(NSWritingDirectionRightToLeft | NSTextWritingDirectionOverride)]};
NSAttributedString *attrString = [[NSAttributedString alloc] initWithData:testData options:attrs documentAttributes:nil error:nil];
NSLog(#"The text of the document is: %#", [attrString string]);
What it is that I need to do to the command line application to attach the document attributes to the NSAttributedString object correctly so that the output is correct?

Answer 1

I don't have an immediate answer, but with regards to this line of code:
NSAttributedString *attrString = [[NSAttributedString alloc] initWithData:currentData options:attrs documentAttributes:nil error:nil];
You should use the error variable to figure out why the result is null / nil. So instead write something like the following:
NSError *error = nil;
NSAttributedString *attrString = [[NSAttributedString alloc] initWithData:currentData options:attrs documentAttributes:nil error:&error];
If (attrString == nil) // parsing failed, so read out error
{
NSLog(#"%#", error);
}
Perhaps this will help you figure out what goes wrong.