How to Apply Sqlite in IOS development

SqliteHowIOS developmentApplication is the content to be introduced in this article, mainly to learnIOS developmentMediumSqlite Database.Sqlite DatabaseInitialize, copy to the user directory, and determine whether or notDatabaseAlready exists, or is the replication successful!

Enter the following code in AppDelegate. m to copy the preset database to the specified doucment directory.

 
 

  
  
-(BOOL) initializeDb {
  
  
NSLog (@ "initializeDB ");
  
  
// Look to see if DB is in known location (~ /Documents/$ DATABASE_FILE_NAME)
  
  
// START: code. DatabaseShoppingList. findDocumentsDirectory
  
  
NSArray * searchPaths = NSSearchPathForDirectoriesInDomains (NSDocumentDirectory, NSUserDomainMask, YES );
  
  
NSString * documentFolderPath = [searchPaths objectAtIndex: 0];
  
  
// View the file directory
  
  
NSLog (@ "% @", documentFolderPath );
  
  
DbFilePath = [documentFolderPath stringByAppendingPathComponent: @ "shopping. db"];
  
  
// END: code. DatabaseShoppingList. findDocumentsDirectory
  
  
[DbFilePath retain];
  
  
// START: code. DatabaseShoppingList. copyDatabaseFileToDocuments
  
  
If (! [[NSFileManager defaultManager] fileExistsAtPath: dbFilePath]) {
  
  
// Didn't find db, need to copy
  
  
NSString * backupDbPath = [[NSBundle mainBundle] pathForResource: @ "shopping" ofType: @ "db"];
  
  
If (backupDbPath = nil ){
  
  
// Couldn't find backup db to copy, bail
  
  
Return NO;
  
  
} Else {
  
  
BOOL copiedBackupDb = [[NSFileManager defaultManager] copyItemAtPath: backupDbPath toPath: dbFilePath error: nil];
  
  
If (! CopiedBackupDb ){
  
  
// Copying backup db failed, bail
  
  
Return NO;
  
  
}
  
  
}
  
  
}
  
  
Return YES;
  
  
// END: code. DatabaseShoppingList. copyDatabaseFileToDocuments
  
  
NSLog (@ "bottom of initializeDb ");
  
  
}
  
  
-(Void) applicationDidFinishLaunching :( UIApplication *) application {
  
  
// Copy the database from the bundle if necessary
  
  
If (! [Self initializeDb]) {
  
  
// TODO: alert the user!
  
  
NSLog (@ "couldn't init db ");
  
  
Return;
  
  
}
  
  
// Add the tab bar controller's current view as a subview of the window
  
  
[Window addSubview: tabBarController. view];
  
  
}
 
 

Summary: DetailsSqliteHowIOS developmentI hope this article will help you!