this class is not key value coding-compliant for the key findContact

Question

I am new to iPhone and trying to connect my iPhone with sqlite. please help me to short out this problem or suggest me a basic step connecting example. I will be really thankfull to you for your this act of kindness. ERROR :

2014-05-17 13:06:20.537 sqlite5[1083:11303] * Terminating app due to uncaught exception 'NSUnknownKeyException', reason: '[ setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key findContact.' * First throw call stack: (0x2090012 0x119de7e 0x2118fb1 0xc4a711 0xbcbec8 0xbcb9b7 0xbf6428 0x3020cc 0x11b1663 0x208b45a 0x300bcf 0x1c5e37 0x1c6418 0x1c6648 0x1c6882 0x115a25 0x115dbf 0x115f55 0x11ef67 0xe2fcc 0xe3fab 0xf5315 0xf624b 0xe7cf8 0x1febdf9 0x1febad0 0x2005bf5 0x2005962 0x2036bb6 0x2035f44 0x2035e1b 0xe37da 0xe565c 0x1b7d 0x1aa5 0x1) libc++abi.dylib: terminate called throwing an exception (lldb)

ViewController.m File -:

//
//  ViewController.m
//  sqlite5
//
//  Created by Techinfiniti on 17/05/14.
//  Copyright (c) 2014 Techinfiniti. All rights reserved.
//

#import "ViewController.h"

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.

    NSString *docsDir;
    NSArray *dirPaths;

    // Get the documents directory
    dirPaths = NSSearchPathForDirectoriesInDomains(
                                                   NSDocumentDirectory, NSUserDomainMask, YES);

    docsDir = dirPaths[0];

    // Build the path to the database file
    _databasePath = [[NSString alloc]
                     initWithString: [docsDir stringByAppendingPathComponent:
                                      @"contacts.db"]];

    NSFileManager *filemgr = [NSFileManager defaultManager];

    if ([filemgr fileExistsAtPath: _databasePath ] == NO)
    {
        const char *dbpath = [_databasePath UTF8String];

        if (sqlite3_open(dbpath, &_contactDB) == SQLITE_OK)
        {
            char *errMsg;
            const char *sql_stmt =
            "CREATE TABLE IF NOT EXISTS CONTACTS (ID INTEGER PRIMARY KEY AUTOINCREMENT, NAME TEXT, ADDRESS TEXT, PHONE TEXT)";

            if (sqlite3_exec(_contactDB, sql_stmt, NULL, NULL, &errMsg) != SQLITE_OK)
            {
                _status.text = @"Failed to create table";
            }
            sqlite3_close(_contactDB);
        } else {
            _status.text = @"Failed to open/create database";
        }
    }

}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

- (IBAction)saveData:(id)sender {


    sqlite3_stmt    *statement;
    const char *dbpath = [_databasePath UTF8String];

    if (sqlite3_open(dbpath, &_contactDB) == SQLITE_OK)
    {

        NSString *insertSQL = [NSString stringWithFormat:
                               @"INSERT INTO CONTACTS (name, address, phone) VALUES (\"%@\", \"%@\", \"%@\")",
                               _name.text, _address.text, _phone.text];

        const char *insert_stmt = [insertSQL UTF8String];
        sqlite3_prepare_v2(_contactDB, insert_stmt,
                           -1, &statement, NULL);
        if (sqlite3_step(statement) == SQLITE_DONE)
        {
            _status.text = @"Contact added";
            _name.text = @"";
            _address.text = @"";
            _phone.text = @"";
        } else {
            _status.text = @"Failed to add contact";
        }
        sqlite3_finalize(statement);
        sqlite3_close(_contactDB);
    }

}


- (IBAction)findContact:(id)sender {

    const char *dbpath = [_databasePath UTF8String];
    sqlite3_stmt    *statement;

    if (sqlite3_open(dbpath, &_contactDB) == SQLITE_OK)
    {
        NSString *querySQL = [NSString stringWithFormat:
                              @"SELECT address, phone FROM contacts WHERE name=\"%@\"",
                              _name.text];

        const char *query_stmt = [querySQL UTF8String];

        if (sqlite3_prepare_v2(_contactDB,
                               query_stmt, -1, &statement, NULL) == SQLITE_OK)
        {
            if (sqlite3_step(statement) == SQLITE_ROW)
            {
                NSString *addressField = [[NSString alloc]
                                          initWithUTF8String:
                                          (const char *) sqlite3_column_text(
                                                                             statement, 0)];
                _address.text = addressField;
                NSString *phoneField = [[NSString alloc]
                                        initWithUTF8String:(const char *)
                                        sqlite3_column_text(statement, 1)];
                _phone.text = phoneField;
                _status.text = @"Match found";
            } else {
                _status.text = @"Match not found";
                _address.text = @"";
                _phone.text = @"";
            }
            sqlite3_finalize(statement);
        }
        sqlite3_close(_contactDB);
    }
}

@end

Answer 1

Check corresponding xib file. In the outlets tab there should be a binding with an exclamation mark. You forgot to remove this binding when you removed findContact property in .h file.