以编程方式使用xib设置IBOutlet和文件所有者会导致键值编码兼容错误

Question

I create a xib. The file owner of the xib is a set to a custom class called PackageTrackingListViewElement . The PackageTrackingListViewElement has an IBOutlet property called contentView , among others. Several views in interface builder are connected to the IBOutlet properties of the custom class called PackageTrackingListViewElement .

I try to initialize an object from the xib.

PackageTrackingListViewElement *element2 = [[[NSBundle mainBundle] loadNibNamed:@"PackageTrackingListViewElementXib" owner:nil options:nil] objectAtIndex:0];

[element2.labelDate setText:@"12/14/15"];
[element2.labelLocation setText:@"Berkeley, California"];

After this, I add the element2 object to a UIStackView.

What am I supposed to set the file owner in loadNibNamed so that I do not get the error that the owner of the xib is not key-value compliant for the properties I am attempting to access?

My error is [<UIStackView 0x165ddc80> setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key contentView.' When I try to set the stackView as the owner of the xib. I know this is wrong of course, but I cannot set the object which has not been created to be its own owner. I do not understand what to do.

Answer 1

Alas figured it out. Many thanks to Instantiating a UIView from a XIB file with itself as the file's owner?

Thank you nebs

PackageTrackingListViewElement.h

#import <UIKit/UIKit.h>

@interface PackageTrackingListViewElement : UIView

@property (nonatomic,strong) IBOutlet UILabel *labelLocation;

- (instancetype)initFromNib;

@end

PackageTrackingListViewElement.m

#import "PackageTrackingListViewElement.h"

@implementation PackageTrackingListViewElement : UIView

- (instancetype)initFromNib {
    return [[[NSBundle mainBundle] loadNibNamed:NSStringFromClass(self.class) owner:nil options:nil] firstObject];
}

@end

You can then simply do:

PackageTrackingListViewElement *myView = [[PackageTrackingListViewElement alloc] initFromNib];


[myView.labelLocation setText:@"text"]; //access properties

By using the instantiation procedure in the link above, I got my instantiation of the xib to work. I set the file-owner of the xib to nothing (NSObject), and instead set the root view (by selecting the view in the xib) to the PackageTrackingListViewElement and connecting all outlets to that view.