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How does [self.tableView reloadData] know what data needs to be reloaded?

It seems to me that my view manager, which is a tableViewController, knows that it is not informed that its NSArray or NSDictionary property contains data that must be loaded into the table for display.

It seems like I should explicitly say something like:

[self.tableView useData:self.MyArray];

I want to have more than one array inside my TableViewController and switch between one and the other programmatically.

I notice that when tableViewController uses searchViewController, you can do this:

if (tableView == self.searchDisplayController.searchResultsTableView) {

I was even able to do this:

self.tableView =  self.searchDisplayController.searchResultsTableView;
[self.tableView reloadData];

But nowhere can I find how to set self.tableView back to the main data source!

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2 answers

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Model-View-Controller, API iPhone/ Cocoa. -, , , , . , Apple Documentation.

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@interface MyDataModel : NSObject {
@protected
    NSArray *arrayOne;
    NSArray *arrayTwo;
@public
    NSArray *currentlyUsedArray;

}
@property(nonatomic, retain)  NSArray *currentlyUsedArray;

-(void) switchToArrayOne;
-(void) switchToArrayTwo;
-(void) toggleUsedArray;

@end

#import "MyDataModel.h"

@interface MyDataModel ()
@property(nonatomic, retain)  NSArray *arrayOne;
@property(nonatomic, retain)  NSArray *arrayTwo;

@end


@implementation MyDataModel

- (id) init{
    if (self=[super init]) {
        self.arrayOne=//... initialize array from some source
        self.arrayTwo=//... initialize array from some source
        self.currentlyUsedArray=self.arrayOne; //whatever default you want
    }
    return self;
}

-(void) switchToArrayOne{
    self.currentlyUsedArray=self.arrayOne;
}

-(void) switchToArrayTwo{
    self.currentlyUsedArray=self.arrayTwo;
}

- (void) toggleUsedArray{
    if (self.currentlyUsedArray==self.arrayOne) {
        self.currentlyUsedArray=self.arrayTwo;
    }else {
        self.currentlyUsedArray=self.arrayOne;
    }
}

( , currentlyUsedArray. , .)

. - , - .

, tableview :

MyDataModel *theDataModel;
@property (nonatomic, retain) MyDataModel *theDataModel;


@synthesize theDataModel;

-(MyDataModel *) theDataModel; {
    if (theDataModel; !=nil) {
        return theDataModel; ;
    }
    id appDelegate=[[UIApplication sharedApplication] delegate];
    self.theDataModel=appDelegate.theDataModelProperty;
    return theDataModel;
}

datasource tableview:

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
    ...
    cell.textLabel.text=[self.theDataModel.currentlyUsedArray objectAtIndex:indexPath.row];
    return cell;
}

- , .

id appDelegate=[[UIApplication sharedApplication] delegate];
[appDelegate.theDataModelProperty toggleUsedArray];

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+41

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. Apple:

UITableView . Model-View-Controller , ( ) ; , , . ( ) , UITableViewController.

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- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath

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