CATextLayer *textLayer = [CATextLayerlayer]; 
    textLayer.frame =CGRectMake(100,100,100,100); 
    [self.view.layeraddSublayer:textLayer]; 
    
    textLayer.foregroundColor = [UIColorblackColor].CGColor; 
    textLayer.alignmentMode =kCAAlignmentJustified; 
    textLayer.wrapped =YES; 
    
    UIFont *font = [UIFontsystemFontOfSize:15]; 
    
    CFStringRef fontName = (__bridgeCFStringRef)font.fontName; 
    CGFontRef fontRef =CGFontCreateWithFontName(fontName); 
    textLayer.font = fontRef; 
    textLayer.fontSize = font.pointSize; 
    CGFontRelease(fontRef); 
    
    NSString *text =@"Cupid laid by his brand, and fell asleep"; 
    
    textLayer.string = text; 
 
    textLayer.contentsScale = [UIScreen mainScreen].scale; // 在Retina显示