我的iOS应用程序从Web查询填充SQLlite数据库（使用FMDB）。有一个UITableView来显示这些数据。自从我开始编写应用程序以来，这个数据库的大小已爆炸到大约10,000条记录。
我目前的设计是从数据库中加载数据，然后在UITableView中使用它。它工作正常，我在屏幕右侧有字母顺序索引，供用户快速访问数据。
问题当然是加载阵列需要15-20秒。我最初设计这个是在每次用户点击UITableView时加载，但这意味着每次15-20秒。
是否有办法在保留搜索功能和索引的同时仅在UITableView中加载某些数据？
我可以/应该加载一次数组并重复使用它吗？我试过了，但似乎无法完成这项工作。
作为最后的手段，我可以切换到CoreData，但我真的不想在中游换马。
UITableView实施：
#import "ContactViewController.h"
#import "ContactDetailViewController.h"
@interface ContactViewController ()
@end
@implementation ContactViewController {
NSMutableArray *_contacts;
UISearchDisplayController *searchController;
BOOL isSearching;
}
- (void)awakeFromNib {
if ([[UIDevice currentDevice] userInterfaceIdiom] ==
UIUserInterfaceIdiomPad) {
self.clearsSelectionOnViewWillAppear = NO;
self.preferredContentSize = CGSizeMake(320.0, 600.0);
}
[super awakeFromNib];
}
- (void)viewDidLoad {
[super viewDidLoad];
// Get array of employees and sections
_contacts = [ContactsDatabase getContacts];
self.sections = [ContactsDatabase getSections:_contacts];
// Set up Search
self.searchDisplayController.displaysSearchBarInNavigationBar = YES;
self.filteredContacts = [NSMutableArray array];
searchController.delegate = self;
searchController.searchResultsDataSource = self;
isSearching = FALSE;
// iPad
// self.dtailViewController = (detailViewController
// *)[[self.splitViewController.viewControllers lastObject]
// topViewController];
// Set the back bar button
UIBarButtonItem *backButton =
[[UIBarButtonItem alloc] initWithTitle:@"Contacts"
style:UIBarButtonItemStylePlain
target:nil
action:nil];
self.navigationItem.backBarButtonItem = backButton;
}
#pragma mark - Table View
- (NSInteger)tableView:(UITableView *)tableView
numberOfRowsInSection:(NSInteger)section {
NSInteger tmpRows;
if (tableView == self.searchDisplayController.searchResultsTableView) {
tmpRows = [self.filteredContacts count];
} else {
tmpRows = [[self.sections
valueForKey:[[[self.sections allKeys]
sortedArrayUsingSelector:
@selector(localizedCaseInsensitiveCompare:)]
objectAtIndex:section]] count];
}
return tmpRows;
}
- (UITableViewCell *)tableView:(UITableView *)tableView
cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = @"Cell";
UITableViewCell *cell =
[tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [self.tableView dequeueReusableCellWithIdentifier:CellIdentifier];
}
if (isSearching) {
contact *thisContact = [self.filteredContacts objectAtIndex:indexPath.row];
cell.textLabel.text = thisContact.cmpNme;
} else {
contact *thisContact = [[self.sections
valueForKey:[[[self.sections allKeys]
sortedArrayUsingSelector:
@selector(localizedCaseInsensitiveCompare:)]
objectAtIndex:indexPath.section]]
objectAtIndex:indexPath.row];
cell.textLabel.text = thisContact.cmpNme;
}
return cell;
}
#pragma mark - Table Sections
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
NSInteger tmpCount;
if (isSearching) {
tmpCount = 1;
} else {
tmpCount = [[self.sections allKeys] count];
}
return tmpCount;
}
- (NSString *)tableView:(UITableView *)tableView
titleForHeaderInSection:(NSInteger)section {
NSString *tmpString;
if (tableView == self.searchDisplayController.searchResultsTableView) {
tmpString = nil;
} else {
tmpString = [[[self.sections allKeys]
sortedArrayUsingSelector:@selector(localizedCaseInsensitiveCompare:)]
objectAtIndex:section];
}
return tmpString;
}
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
if ([[segue identifier] isEqualToString:@"showContactDetail"]) {
contact *dtlContact;
if (isSearching) {
dtlContact = [self.filteredContacts
objectAtIndex:self.searchDisplayController.searchResultsTableView
.indexPathForSelectedRow.row];
} else {
dtlContact = [[self.sections
valueForKey:[[[self.sections allKeys]
sortedArrayUsingSelector:
@selector(localizedCaseInsensitiveCompare:)]
objectAtIndex:[self.tableView indexPathForSelectedRow]
.section]]
objectAtIndex:[self.tableView indexPathForSelectedRow].row];
}
self.contactDetailViewController.detailItem = dtlContact;
[[segue destinationViewController] setDetailItem:dtlContact];
}
}
#pragma mark - Right side bar alphabetical index
- (NSArray *)sectionIndexTitlesForTableView:(UITableView *)tableView {
NSArray *tmpTitle;
if (isSearching) {
tmpTitle = nil;
} else {
tmpTitle = [[self.sections allKeys]
sortedArrayUsingSelector:@selector(localizedCaseInsensitiveCompare:)];
}
return tmpTitle;
}
#pragma mark - Search methods
- (void)searchDisplayControllerWillBeginSearch:
(UISearchDisplayController *)controller {
isSearching = TRUE;
self.searchDisplayController.searchBar.showsCancelButton = YES;
[self.tableView reloadSectionIndexTitles];
}
- (void)searchDisplayControllerDidEndSearch:
(UISearchDisplayController *)controller {
isSearching = FALSE;
self.searchDisplayController.searchBar.showsCancelButton = NO;
[self.tableView reloadSectionIndexTitles];
}
- (void)filterContentForSearchText:(NSString *)searchText
scope:(NSString *)scope {
[self.filteredContacts removeAllObjects];
NSPredicate *predicate =
[NSPredicate predicateWithFormat:@"cmpNme contains[c] %@", searchText];
NSArray *tempArray = [_contacts filteredArrayUsingPredicate:predicate];
// Move to filtered array
self.filteredContacts = [NSMutableArray arrayWithArray:tempArray];
self.sections = [ContactsDatabase getSections:_contacts];
}
- (BOOL)searchDisplayController:(UISearchDisplayController *)controller
shouldReloadTableForSearchString:(NSString *)searchString {
isSearching = TRUE;
[self
filterContentForSearchText:searchString
scope:[self.searchDisplayController.searchBar
.scopeButtonTitles
objectAtIndex:
self.searchDisplayController.searchBar
.selectedScopeButtonIndex]];
return YES;
}
@end
getContacts方法
+ (NSMutableArray *)getContacts {
id tmpDatabasePath = [(AppDelegate *)
[[UIApplication sharedApplication] delegate] databasePathContacts];
NSMutableArray *tmpContacts;
tmpContacts = [[NSMutableArray alloc] init];
FMDatabase *db = [FMDatabase databaseWithPath:tmpDatabasePath];
[db open];
FMResultSet *results =
[db executeQuery:@"SELECT * FROM contacts ORDER by cmpNme"];
while ([results next]) {
contact *thisContact = [contact new];
thisContact.cmpNme = [results stringForColumn:@"cmpNme"];
thisContact.fstNme = [results stringForColumn:@"fstNme"];
thisContact.lstNme = [results stringForColumn:@"lstNme"];
thisContact.cntTyp = [results stringForColumn:@"cnttyp"];
NSString *tst = [results stringForColumn:@"phnNbr"];
thisContact.phnNbr = [NSNumber numberWithInt:[tst intValue]];
thisContact.adr1 = [results stringForColumn:@"adr1"];
thisContact.adr2 = [results stringForColumn:@"adr2"];
thisContact.cty = [results stringForColumn:@"cty"];
thisContact.ste = [results stringForColumn:@"ste"];
tst = [results stringForColumn:@"zip"];
thisContact.zip = [NSNumber numberWithInt:[tst intValue]];
thisContact.ema = [results stringForColumn:@"ema"];
tst = [results stringForColumn:@"id"];
thisContact.id = [NSNumber numberWithInt:[tst intValue]];
[tmpContacts addObject:thisContact];
}
[db close];
return tmpCon