Can I add labels to a xib programmatically from a separate class which is a NSObject subclass?

Question

I have a project in which I am creating a PDF. I have a xib, "PDFView" which lays out the background image and labels. Everything else is drawn on the PDF from my PDFRenderer class which is a NSObject class. I am trying to make it so the text shown in the labels is data previously entered by a user on a previous screen. Here is my code:

PDFRenderer.h

#import <Foundation/Foundation.h>
#import <CoreText/CoreText.h>
#import "Storage.h"

@interface PDFRenderer : NSObject

+(void)drawPDF:(NSString*)fileName;

+(void)drawText:(NSString*)textToDraw inFrame:(CGRect)frameRect;

+(void)drawLogo;


@end

PDFRenderer.m

#import "PDFRenderer.h"

@implementation PDFRenderer

+(void)drawLabels
{
    NSArray* objects = [[NSBundle mainBundle] loadNibNamed:@"PDFView" owner:nil options:nil];
    UIFont *font = [UIFont systemFontOfSize:8];
    NSDictionary *text = [[NSDictionary alloc] initWithObjectsAndKeys: font, NSFontAttributeName,
                                nil];

    UIView* mainView = [objects objectAtIndex:0];

    for (UIView* view in [mainView subviews]) {
        if([view isKindOfClass:[UILabel class]])
        {
            UILabel* label = (UILabel*)view;

            [label.text drawInRect:label.frame withAttributes: text];
        }
    }
}

+(void)drawImage:(UIImage*)image inRect:(CGRect)rect
{

    [image drawInRect:rect];

}

+(void)drawLogo
{
    NSArray* objects = [[NSBundle mainBundle] loadNibNamed:@"PDFView" owner:nil options:nil];

    UIView* mainView = [objects objectAtIndex:0];

    for (UIView* view in [mainView subviews]) {
        if([view isKindOfClass:[UIImageView class]])
        {
            UIImage* logo = [UIImage imageNamed:@"JmHaloReportImage.png"];
            [self drawImage:logo inRect:view.frame];
        }
    }
}

+(void)drawPDF:(NSString*)fileName
{
    // Create the PDF context using the default page size of 612 x 792.
    UIGraphicsBeginPDFContextToFile(fileName, CGRectZero, nil);
    // Mark the beginning of a new page.
    UIGraphicsBeginPDFPageWithInfo(CGRectMake(0, 0, 612, 792), nil);

    [self drawLogo];
    [self drawLabels];

    // Close the PDF context and write out the contents.
    UIGraphicsEndPDFContext();
}

+(void)drawText:(NSString*)textToDraw inFrame:(CGRect)frameRect
{
    CFStringRef stringRef = (__bridge CFStringRef)textToDraw;
    // Prepare the text using a Core Text Framesetter.
    CFAttributedStringRef currentText = CFAttributedStringCreate(NULL, stringRef, NULL);
    CTFramesetterRef framesetter = CTFramesetterCreateWithAttributedString(currentText);

    CGMutablePathRef framePath = CGPathCreateMutable();
    CGPathAddRect(framePath, NULL, frameRect);

    // Get the frame that will do the rendering.
    CFRange currentRange = CFRangeMake(0, 0);
    CTFrameRef frameRef = CTFramesetterCreateFrame(framesetter, currentRange, framePath, NULL);
    CGPathRelease(framePath);

    // Get the graphics context.
    CGContextRef    currentContext = UIGraphicsGetCurrentContext();

    // Put the text matrix into a known state. This ensures
    // that no old scaling factors are left in place.
    CGContextSetTextMatrix(currentContext, CGAffineTransformIdentity);

    // Core Text draws from the bottom-left corner up, so flip
    // the current transform prior to drawing.
    // Modify this to take into consideration the origin.
    CGContextTranslateCTM(currentContext, 0, frameRect.origin.y*2 + frameRect.size.height);
    CGContextScaleCTM(currentContext, 1.0, -1.0);

    // Draw the frame.
    CTFrameDraw(frameRef, currentContext);


    // Add these two lines to reverse the earlier transformation.
    CGContextScaleCTM(currentContext, 1.0, -1.0);
    CGContextTranslateCTM(currentContext, 0, (-1)*(frameRect.origin.y*2 + frameRect.size.height));

    CFRelease(frameRef);
    //CFRelease(stringRef);
    CFRelease(framesetter);
}

@end

Each of my labels in the xib has a separate tag. I don't understand how to reference each individual label by tag. Any assistance? I am completely lost and trying to learn.

Answer 1

You're almost there:

    // before the @implementation, using the tag values you setup in your xib
    #define kTAG_FOR_ONE_OF_MY_LABELS 64
    #define kTAG_FOR_ANOTHER_LABEL    65

    UIView* mainView = [objects objectAtIndex:0];
    UILabel *oneOfMyLabels = (UILabel *)[mainView viewWithTag:kTAG_FOR_ONE_OF_MY_LABELS];
    UILabel *anotherLabel = (UILabel *)[mainView viewWithTag:kTAG_FOR_ANOTHER_LABEL];