iPhone-Entwicklung - eine Andere Frage auf resizng UILabel & custom UITableViewCell

Ich habe folgende Funktion in einige meiner Projekte, aber vor kurzem habe ich ein kleines Beispiel, die behaupten, dass es nicht zuverlässig (zumindest in manchen Situationen):

[NSString sizeWithFont:font constrainedToSize:size]
[NSString sizeWithFont:font constrainedToSize:size lineBreakMode:lineBreak]

Erstellte ich eine custom UITableViewCell Klasse zu erreichen, die Ergebnisse, wie gesehen in den iPhone-Foto-Album-Anwendung, wie z.B. Bild, mit Album-Name, und die Anzahl der Bilder im album. Ich habe die oben genannten Funktion stellen Sie meine detail-text - (für count). Hier ist der code:

Interface File:

#import <UIKit/UIKit.h>

@interface CustomValue2Cell : UITableViewCell {
    UIImageView *cellImage;
    UILabel *cellTextLabel;
    UILabel *cellDetailTextLabel;
}

@property (nonatomic, retain) UIImageView *cellImage;
@property (nonatomic, retain) UILabel *cellTextLabel;
@property (nonatomic, retain) UILabel *cellDetailTextLabel;

- (void)setCellImage:(UIImage *)image withText:(NSString *)text andDetail:(NSString *)detail;
- (CGSize)getSizeOfText:(NSString *)text withFont:(UIFont *)font;

@end

Implementation File:

#import "CustomValue2Cell.h"

@implementation CustomValue2Cell

@synthesize cellImage;
@synthesize cellTextLabel;
@synthesize cellDetailTextLabel;

//Coordinate positions of Image, Text Label, and Detail Text Label
# define kImageXPosition    3
# define kImageYPosition    3
# define kImageWidth        37.0
# define kImageHeight       37.0

# define kTextXPosition     55
# define kTextYPosition     10
# define kTextWidth         200
# define kTextHeight        22

# define kDetailXPosition   55
# define kDetailYPosition   10
# define kDetailWidth       40
# define kDetailHeight      22

//Displacement value for Text Label with Detail Text Label
//Displacement value of 10-15 works with non-bold font
# define kCellSubviewDisplacement   20  

//Label Font Size for Text Label and Detail Text Label
# define kTextLabelFontSize     18
# define kDetailLabelFontSize   16

- (id)initWithFrame:(CGRect)frame reuseIdentifier:(NSString *)reuseIdentifier {
    if (self = [super initWithFrame:frame reuseIdentifier:reuseIdentifier]) {

        //Color and font for the main label
        UIColor *textLabelColor = [UIColor blackColor];
        UIFont *textLabelFont = [UIFont systemFontOfSize:kTextLabelFontSize];

        //Color and font for the detail label
        UIColor *detailTextColor = [UIColor darkGrayColor];
        UIFont *detailTextFont = [UIFont systemFontOfSize:kDetailLabelFontSize];

        //Highligted row color
        UIColor *highlightedTextColor = [UIColor whiteColor];

        //Define boundary of the cell contents
        CGRect rect;

        //Set properties of Image Thumbnail
        rect = CGRectMake(kImageXPosition, kImageYPosition, kImageWidth, kImageHeight);
        cellImage = [[UIImageView alloc] initWithFrame:rect];

        //Set properties of Name
        rect = CGRectMake(kTextXPosition, kTextYPosition, kTextWidth, kTextHeight);
        cellTextLabel = [[UILabel alloc] initWithFrame:rect];
        [cellTextLabel setFont:textLabelFont];
        [cellTextLabel setTextColor:textLabelColor];
        [cellTextLabel setHighlightedTextColor:highlightedTextColor];

        //Set properties of Value
        rect = CGRectMake(kDetailXPosition, kDetailYPosition, kDetailWidth, kDetailHeight);
        cellDetailTextLabel = [[UILabel alloc] initWithFrame:rect];
        [cellDetailTextLabel setFont:detailTextFont];
        [cellDetailTextLabel setTextColor:detailTextColor];
        [cellDetailTextLabel setHighlightedTextColor:highlightedTextColor];

        //Put Image, Name, and Value in Content View
        [[self contentView] addSubview:cellImage];
        [[self contentView] addSubview:cellTextLabel];
        [[self contentView] addSubview:cellDetailTextLabel];

        //Set cell selection style (Blue)
        self.selectionStyle = UITableViewCellSelectionStyleBlue;
    }
    return self;
}

- (void)setCellImage:(UIImage *)image withText:(NSString *)text andDetail:(NSString *)detail {
    cellImage.image = image;
    cellTextLabel.text = text;
    cellDetailTextLabel.text = detail;

    //Get an estimated size of text in the label, 
    //which will be used to estimate the position of detail label
    UIFont *textLabelFont = [UIFont systemFontOfSize:kTextLabelFontSize];
    CGSize size = [self getSizeOfText:text withFont:textLabelFont];

    //Re-set the frame of detail view
    CGRect frame = CGRectMake(kDetailXPosition, kDetailYPosition, kDetailWidth, kDetailHeight);
    frame.origin.x = frame.origin.x + size.width + kCellSubviewDisplacement;
    [cellDetailTextLabel setFrame:frame];
}

- (CGSize)getSizeOfText:(NSString *)text withFont:(UIFont *)font {
    return [text sizeWithFont:font constrainedToSize:CGSizeMake(kTextWidth, kTextHeight)];
}

- (void)setSelected:(BOOL)selected animated:(BOOL)animated {
    [super setSelected:selected animated:animated];
    //Configure the view for the selected state
}

- (void)dealloc {
    [cellImage release];
    [cellTextLabel release];
    [cellDetailTextLabel release];
    [super dealloc];
}

@end

Testen meine custom class bereitete ich eine Liste von fonts angezeigt und Sie in meiner Tabelle Anzeigen. Code zum abrufen der Liste der verfügbaren Schriftarten:

fontFamily = [[NSMutableArray alloc] initWithArray:[UIFont familyNames]];
fonts = [[NSMutableArray alloc] init];

for(NSUInteger i=0; i<[fontFamily count]; i++) {
    NSString *familyName = [fontFamily objectAtIndex:i];
    NSArray *array = [UIFont fontNamesForFamilyName:familyName];
    [fonts addObjectsFromArray:array];
}

Hier ist der code zur Rückgabe der Zellen:

//Customize the appearance of table view cells.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    static NSString *CellIdentifier = @"Cell";
    CGRect rect = CGRectMake(0.0, 0.0, 320.0, 50.0);

    CustomValue2Cell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
    if (cell == nil) {
        cell = [[[CustomValue2Cell alloc] initWithFrame:rect reuseIdentifier:CellIdentifier] autorelease];
    }

    NSString *font = [fonts objectAtIndex:indexPath.row];
    NSString *detail = [NSString stringWithFormat:@"%d", [[fonts objectAtIndex:indexPath.row] length]];

    [cell setCellImage:[UIImage imageNamed:@"Pointy.gif"] withText:font andDetail:detail];
    [cell setAccessoryType:UITableViewCellAccessoryDisclosureIndicator]
    return cell;
}

Result: Text Label and Detail Text Label are overlapping for some values. e.g. "CouierNewPS-BoldMT" and "25" overlap each other, and in some other cases, they are not overlapping but they are very close.

Question: Is their a better alternative to -sizeWithFont function? Or, am i doing something very stupid to mess things up?

Sorry für die lange post. Jede Hilfe ist willkommen. Dankend in Erwartung.