«
»

NSLogTable improvements

July 22, 2010, 7:57 pm

Are you tired of seeing the date, time (with seconds and even milliseconds), application name and other stuffs appearing at the beginning of each and every line of the debugging console? You know, the NSLog lines that you use for debugging purposes that look like this:

2010-07-22 20:42:46.998 MyApplicationName[246:207] Setting up reachability notifier
2010-07-22 20:42:47.006 MyApplicationName[246:207] Version: 0.6
2010-07-22 20:42:47.007 MyApplicationName[246:207] Checking for database
2010-07-22 20:42:47.007 MyApplicationName[246:207] Database exists

This information can be helpful, but for the purposes of my utility class that outputs the contents of a SQLite3 database table (see my blog post entitled Nicely formatted data to debugger console for iPhone SDK), this is very annoying as it takes up a lot of the debugging console window.

Well, I decided to look to see if I could output to the debugging and remove the date, time, and application name from the beginning of each line. As it turns out, I found that you cannot do this with NSLog, but luckily I found the following web page that contained the answer:

A Different NSLog() (link redacted, no longer available)

Even though the web page is for Cocoa development, there is nothing Mac OS X specific looking in there, so I copied the QuietLog function and pasted it into my NSLogTable implementation file, and now I can see much more of my nicely formatted tables since the left 33% of my screen is not filled up with useless dates, times, application names, and thread identifiers.

Here is now what my NSLogTable.m file looks like. (The NSLogTable.h file is unchanged.)

//
//  NSLogTable.m
//
 
#import "NSLogTable.h"
 
@implementation NSLogTable
 
void QuietLog (NSString *format, ...) 
{
    if (format == nil) {
        printf("nil\n");
        return;
    }
 
    // Get a reference to the arguments that follow the format parameter
    va_list argList;
    va_start(argList, format);
 
    // Perform format string argument substitution, reinstate %% escapes, then print
    NSString *s = [[NSString alloc] initWithFormat:format arguments:argList];
    printf("%s\n", [[s stringByReplacingOccurrencesOfString:@"%%" withString:@"%%%%"] UTF8String]);
 
    [s release];
    va_end(argList);
}
 
+ (void)dumpTable:(NSMutableArray *)rows
{
	int idx = 0;
	NSMutableArray *rowData;
	int colWidths[100];
	NSString *s;
	NSMutableString *ms = [[NSMutableString alloc] init];
	BOOL firstRow = YES;
 
	for (int i = 0; i < 100; i++) colWidths[i] = 0;
 
	// get the maximum column widths
	for (id row in rows)
	{
		rowData = (NSMutableArray *)row;
		for (int i = 0; i < [rowData count]; i++)
		{
			s = [rowData objectAtIndex:i];
			if ([s length] > colWidths[i])
			{
				colWidths[i] = [s length];
			}
		}
	}
 
	for (id row in rows)
	{
		[ms setString:@""];
		if (firstRow)
		{
			[ms appendString:@"     "];
			firstRow = NO;
		} else {
			[ms appendFormat:@"%4d ", idx];
		}		
 
		rowData = (NSMutableArray *)row;
		for (int i = 0; i < [rowData count]; i++)
		{
			s = [rowData objectAtIndex:i];
			[ms appendString:[s stringByPaddingToLength:colWidths[i] withString:@" " startingAtIndex:0]];
			[ms appendString:@" "];
		}
 
		QuietLog(@"%@", ms);
		idx++;
	}
 
	[ms release];
	QuietLog(@"");
}
 
@end
Tags:
Category: iPhone  |  Comment (RSS)  |  Trackback

Leave a Reply