iOS的NSArray從SQLite在UITableView的NSDictionaries

Question

我一直在努力爭取過去兩天這個問題，我似乎無法弄清楚。我有一個具有以下結構的SQlite數據庫。

它是一個列表和List_Items

我訪問數據庫，並創建一個對象，然後將其添加到被添加到一個的NSArray NSDictionary的之間一對多的關係。我做了兩次，一次用於List表，一次用於List_Items。 然後我使用列表數組來計算我的tableview行的列表數，然後將它們添加到tableview。

的問題出現時，我得到的方法

-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath 

我似乎無法弄清楚如何匹配的列表和List_Items的記錄，以顯示屬於該名單列表中的項目一個向下鑽取tableview。因爲我的心在這一點玉米粥

具體代碼示例會有幫助:(

下面是相關的代碼，我有多達我目前Writersblock。

//#******************************************************# 

//    *******Start Database******* 

//#******************************************************# 

-(void)checkAndCreateDatabase 
{ 
    // Check if the SQL database has already been saved to the users phone, if not then copy it over 
    BOOL success; 

    // Create a FileManager object, we will use this to check the status 
    // of the database and to copy it over if required 
    NSFileManager *fileManager = [NSFileManager defaultManager]; 

    // Check if the database has already been created in the users filesystem 
    success = [fileManager fileExistsAtPath:databasePath]; 

    // If the database already exists then return without doing anything 
    if(success) return; 

    // If not then proceed to copy the database from the application to the users filesystem 

    // Get the path to the database in the application package 
    NSString *databasePathFromApp = [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:databaseName]; 

    // Copy the database from the package to the users filesystem 
    [fileManager copyItemAtPath:databasePathFromApp toPath:databasePath error:nil]; 
} 

-(void)readItemsFromDatabase 
{ 
    // Setup the database object 
    sqlite3 *database; 

    // Init the Items Array 
    items = [[NSMutableArray alloc] init]; 
    lists = [[NSMutableArray alloc] init]; 

    //---------------### SELECT THE LISTS #####---------------// 

    // Open the database from the users filessytem 
    if(sqlite3_open([databasePath UTF8String], &database) == SQLITE_OK) 
    { 
     NSLog(@"SQL Opened"); 
     // Setup the SQL Statement and compile it for faster access 
     const char *sqlStatement = "SELECT * from List"; 
     sqlite3_stmt *compiledStatement; 
     if(sqlite3_prepare_v2(database, sqlStatement, -1, &compiledStatement, NULL) == SQLITE_OK) { 
      // Loop through the results and add them to the array 
      while(sqlite3_step(compiledStatement) == SQLITE_ROW) { 
       // Read the data from the result row 
       NSString *aListName = [NSString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, 1)]; 
       NSString *aUserID = [NSString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, 2)]; 
       NSString *aListID = [NSString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, 3)]; 

       NSLog(@"SQL Compiled"); 

       // Create a new list object with the data from the database 
       List *list = [[List alloc] initWithlistName:(NSString *)aListName userID:(NSString *)aUserID listID:(NSString *)aListID]; 

       listNames = [NSDictionary dictionaryWithObjectsAndKeys:list.listName,@"listName",list.listID,@"listID",list.listID,@"listID",nil]; 

       // Add the Shopping object to the list Array 
       [lists addObject:listNames]; 

      } 
     } 

     else { NSLog(@"Database Not Found");} 

     // Release the compiled statement from memory 
     sqlite3_finalize(compiledStatement); 
    } 
    sqlite3_close(database); 

     //---------------### SELECT THE LIST_ITEMS #####---------------// 

     if(sqlite3_open([databasePath UTF8String], &database) == SQLITE_OK) 
     { 
      NSLog(@"SQL Opened"); 
      // Setup the SQL Statement and compile it for faster access 
      const char *sqlStatement = "SELECT * from List_Items"; 
      sqlite3_stmt *compiledStatement; 
      if(sqlite3_prepare_v2(database, sqlStatement, -1, &compiledStatement, NULL) == SQLITE_OK) { 
       // Loop through the results and add them to the array 
       while(sqlite3_step(compiledStatement) == SQLITE_ROW) { 
        // Read the data from the result row 

        NSString *aBrandName = [NSString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, 1)]; 
        NSString *aItemName = [NSString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, 2)]; 
        NSString *aItemQuantity = [NSString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, 4)]; 
        NSString *aImageUrl = [NSString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, 5)]; 
        NSString *aListID = [NSString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, 6)]; 

        NSLog(@"SQL Compiled"); 

        // Create a new items object with the data from the database 
        Shopping *shopping = [[Shopping alloc] initWithlistID:(NSString *)aListID brandName:(NSString *)aBrandName itemName:(NSString *)aItemName itemQuantity:(NSString *)aItemQuantity imageURL:(NSString *)aImageUrl];      

        itemList = [NSDictionary dictionaryWithObjectsAndKeys:shopping.listID,@"listID",shopping.brandName,@"brandName",shopping.itemName,@"itemName",shopping.itemQuantity,@"itemQuantity",shopping.imageURL,@"imageURL",nil]; 

        // Add the Shopping object to the items Array 
        [items addObject:itemList]; 
       } 
      } 

      else { NSLog(@"Database Not Found");} 

      // Release the compiled statement from memory 
      sqlite3_finalize(compiledStatement); 

     NSLog(@"%@",items); 
     NSLog(@"%@",lists); 

    } 
    sqlite3_close(database); 

} 

//#******************************************************# 

//    *******END Database******* 

//#******************************************************# 

-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section 
{ 
    int rowcount; 
    rowcount = [lists count]; 
    return rowcount; 
} 

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

    static NSString *CellIdentifier = @"Cell"; 

    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier]; 
    if (cell == nil) 
    { 
     cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault 
             reuseIdentifier:CellIdentifier];  
    } 

    // Set up the cell... 

    NSString *cellValue = [[lists objectAtIndex:indexPath.row] objectForKey:@"listName"]; 

    cell.textLabel.text = cellValue; 

    return cell; 
} 

-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath 
{ 

    if ([[lists objectAtIndex:indexPath.row] objectForKey:@"listID"] != NULL) 
    {   
     NSString *listIndex = [[lists objectAtIndex:indexPath.row] objectForKey:@"listID"]; 
     int i = [listIndex intValue]; 
     NSLog(@"indexPath: %d",i); 
    } 

} 

編輯**** ******

的單個SQL語句返回多個列表名，這是一個問題，因爲我只需要每個列表的名字之一。

Answer 1

任何有興趣我這是怎麼了ened計算出來。 我得到列表的listID，然後我創建一個數組並循環列表項，並將它們與listID進行比較。如果它們與listID相同，我將它們添加到數組中，一旦它完成for循環，它會將結果添加到我的數據對象協議（以使其可用於下一個視圖），然後提交一個模式視圖控制器並加載來自數據對象的數組。一旦我完成了模態視圖，我將數據對象重新設置爲零和Tada！有用。

-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath 
{ 

    if ([[lists objectAtIndex:indexPath.row] objectForKey:@"listID"] != NULL) 
    {   
     [listTableView deselectRowAtIndexPath:indexPath animated:YES]; 
     NSString *listIndex = [[lists objectAtIndex:indexPath.row] objectForKey:@"listID"]; 

     NSMutableArray *itemArray = [[NSMutableArray alloc]init]; 

     int i; int itemCount = [items count]; 

     for (i = 0; i < itemCount; i++) 
     { 
      if ([[[items objectAtIndex:i] objectForKey:@"listID"] isEqual:listIndex]) 
      { 
       [itemArray addObject:[items objectAtIndex:i]]; 
       NSLog(@"Item Array:%@",itemArray); 
      } 
     } 

     if (i == itemCount) 
     { 
      AppDataObject* theDataObject = [self theAppDataObject]; 
      theDataObject.itemArray = itemArray; 

      ItemView *temp = [[ItemView alloc] initWithNibName:@"ItemView" bundle:nil]; 
      [self presentModalViewController: temp animated: YES]; 
     } 

    } 

} 

Answer 2

因此，首先創建一個List對象，然後創建一個與List對象非常相似的NSDictionary對象。爲什麼？爲什麼不直接將List對象添加到數組中。如果您沒有對List項目的屬性執行任何功能，那麼根本不要使用List對象，只需將這些字段直接放在NSDictionary中即可。

其次，不要做兩個不同的SQL調用來獲取信息，只能使用一個來同時獲取該列表的list和list_items。然後，如果您使用的是List對象，請添加一個NSMutableArray屬性調用項目，然後將listItems添加到該數組中。你可以在NSDictionary中做同樣的事情，只需爲關鍵項添加一個NSMutableArray對象，然後將list_items添加到該數組中。

現在你可以設置tableview來做你想做的事情。響應

修訂回答下面的評論

Select * FROM List, List_Items WHERE List.list_id = List.list_id