Cant call delegate method from my protocol class - ios

Question

I have a protocol in one class:
#protocol DataStorageManager
- (void) saveFile;
#end
#interface DataManager : NSObject
{
id <DataStorageManager> delegate;
}
#property (nonatomic, assign) id<DataStorageManager> delegate;
//methods
#end
and its implementation:
#implementation DataManager
#synthesize delegate;
#end
and I have another class which is the adapter between the first and the third one:
#import "DataManager.h"
#import "DataPlistManager.h"
#interface DataAdapter : NSObject <DataStorageManager>
#property (nonatomic,strong) DataPlistManager *plistManager;
- (void) saveFile;
#end
and its implementation
#import "DataAdapter.h"
#implementation DataAdapter
-(id) initWithDataPlistManager:(DataPlistManager *) manager
{
self = [super init];
self.plistManager = manager;
return self;
}
- (void) saveFile
{
[self.plistManager savePlist];
}
#end
So when I in first method try to call my delegate method like this
[delegate saveFile];
Nothing happened. I don't understand what's wrong with the realization - it's a simple adapter pattern realization. So I need to use the delegate which will call the methods from the third class. Any help?

Answer 1

You are not setting the delegate property. You need to do this,
-(id) initWithDataPlistManager:(DataPlistManager *) manager
{
self = [super init];
self.plistManager = manager;
self.plistManager.delegate = self;
return self;
}
Also, in DataManager class remove the ivar declaration, just declaring property is sufficient, the ivar gets automatically created. Call the delegate method as below,
if([self.delegate respondsToSelector:#selector(saveFile)] {
[self.delegate saveFile];
}
Hope that helps!

Answer 2

In your case you forget to set your protocol delegate and also need to call protocol method
by self.delegate....
I just Give Basic Idea for how to Create Protocol
Also Read This Question
#DetailViewController.h
#import <UIKit/UIKit.h>
#protocol MasterDelegate <NSObject>
-(void) getButtonTitile:(NSString *)btnTitle;
#end
#interface DetailViewController : MasterViewController
#property (nonatomic, assign) id<MasterDelegate> customDelegate;
#DetailViewController.m
if([self.customDelegate respondsToSelector:#selector(getButtonTitile:)])
{
[self.customDelegate getButtonTitile:button.currentTitle];
}
#MasterViewController.m
create obj of DetailViewController
DetailViewController *obj = [[DetailViewController alloc] init];
obj.customDelegate = self;
[self.navigationController pushViewController:reportTypeVC animated:YES];
and add delegate method in MasterViewController.m for get button title.
#pragma mark -
#pragma mark - Custom Delegate Method
-(void) getButtonTitile:(NSString *)btnTitle;
{
NSLog(#"%#", btnTitle);
}