在UITableViewCell onload中更改UIButton顏色

Question

我有一個聯繫人列表，應用程序可以添加/查看詳細信息。我在我的自定義UITableViewCell中添加了一個星形按鈕，它用於「收藏夾」功能。如果聯繫人爲'已收藏'，我希望我的按鈕爲黃色，如果不是，請選擇灰色。這是我的代碼。

UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier 
                  forIndexPath:indexPath]; 

ContactUtilities *cu = [[ContactUtilities alloc]init]; 

NSMutableDictionary *listToUse = [NSMutableDictionary new]; 

if([self.txtSearchContacts.text isEqualToString:@""]){ 
    listToUse = self.contactList; 
} else { 
    listToUse = searchContactList; 
} 


NSArray *keyList = [listToUse allKeys]; 
NSString *search = [keyList objectAtIndex:indexPath.row]; 
Contact *contact = [[Contact alloc]init]; 
contact = [cu searchContact:search :listToUse]; 

//Tagging 
UILabel *lblContactName = [cell.contentView viewWithTag:ContactCellElementName]; 
UIImageView *imgContactPic = [cell.contentView viewWithTag:ContactCellElementImage]; 
UILabel *lblContactCompany = [cell.contentView viewWithTag:ContactCellElementCompany]; 
UILabel *lblContactNumber = [cell.contentView viewWithTag:ContactCellElementNumber]; 
UIButton *isFavorite  = (UIButton *)[cell viewWithTag:ContactCellElementButton]; 

UIImage* image = [UIImage imageNamed:contact.imageName]; 

CGImageRef cgref = [image CGImage]; 
CIImage *cim = [image CIImage]; 

if (cim == nil && cgref == NULL) 
{ 
    image = [UIImage imageNamed:@"Person"]; 
} 

lblContactName.text = contact.contactName; 
imgContactPic.image = image; 
lblContactCompany.text = contact.contactCompanyName; 
lblContactNumber.text = contact.contactPhoneNumber; 

//This is where it doesn't work.. 
if([contact.isFavorite isEqualToString:@"YES"]){ 
    [isFavorite setTitleColor:[UIColor yellowColor] forState:UIControlStateNormal]; 
} else { 
    [isFavorite setTitleColor:[UIColor grayColor] forState:UIControlStateNormal]; 
} 

//I also have a property that will check if you will show the button. This is working already. 

if([contact.shouldShow isEqualToString:@"No"]){ 
    [isFavorite removeFromSuperview]; 
} 

cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator; 
return cell; 
} 

這是我的cellForRowAtIndexPath代碼。我目前正在嘗試setTitleColor屬性，但它不起作用。與setTintColor相同，它也不起作用。

Answer 1

色調是你想要的，但它只適用於圖像是帶有alpha通道的PNG，並且圖像的渲染模式被設置爲模板。參考this answer。如果您將圖像分配到故事板中的按鈕，則可以在asset library中設置渲染模式。