Question

经过大量搜索后，没有找到更新 tableview

的正确解决方案

我想更新我的tableview，就像新的记录应该放在先前更新的记录之下。

这是我的代码

if (sqlite3_open(myDatabase, &myConnection) == SQLITE_OK)
{
    sqliteQuery = [NSString stringWithFormat: @"SELECT  Description, SalePrice FROM ProductDetails WHERE Barcode = \'%@\'", barcode];
    if (sqlite3_prepare_v2(myConnection, [sqliteQuery UTF8String], -1, &sQLStatement, NULL) == SQLITE_OK)
    {
        if(sqlite3_step(sQLStatement) == SQLITE_ROW)
        {
                temp = [[NSString alloc] initWithUTF8String:(const char *) sqlite3_column_text(sQLStatement, 0)];
            }
            temp1 = [NSString stringWithFormat:@"%d", value];
            if ([temp1 isEqualToString:@"0"])
            {temp1 = @"1";}
               temp2 = [[NSString alloc] initWithUTF8String:(const char *) sqlite3_column_text(sQLStatement, 1)]                    }
            }
            [description addObject: temp];
            [qty addObject: temp1];
            [price addObject:temp2];
        }
        sqlite3_finalize(sQLStatement);
    }
    sqlite3_close(myConnection);
}
myTable.hidden = NO;
myTable.delegate = self;
myTable.dataSource = self;
[myTable reloadData];
[self.view endEditing:YES];

和tableview数据源委托方法

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
return 1;
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
return [description count];
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath: (NSIndexPath *)indexPath
{
// Configure the cell in each row
static NSString *CellIdentifier = @"Cell";
UITableViewCell *cell;
cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
cell = [self getCellContentView:CellIdentifier];

UILabel *lbl11 = (UILabel *)[cell viewWithTag:1];
[lbl11 setText:@"Label1"];
UILabel *lbl21 = (UILabel *)[cell viewWithTag:2];
[lbl21 setText:@"Label2"];
UILabel *lbl31 = (UILabel *)[cell viewWithTag:3];
[lbl31 setText:@"Label3"];

lbl11.text = [description objectAtIndex:indexPath.row];
lbl21.text = [qty objectAtIndex:indexPath.row];
lbl31.text = [price objectAtIndex:indexPath.row];
   return cell;
}

- (UITableViewCell *)getCellContentView:(NSString *)cellIdentifier
{
UITableViewCell *cell = [[UITableViewCell alloc]   initWithStyle:UITableViewCellStyleValue1 reuseIdentifier:cellIdentifier];
cell.backgroundColor=[UIColor clearColor];

CGRect lbl11Rect = CGRectMake(20, 5, 450, 30);
CGRect lbl21Rect = CGRectMake(545, 5, 150, 30);
CGRect lbl31Rect = CGRectMake(795, 5, 150, 30);

UILabel *lbl11 = [[UILabel alloc] initWithFrame:lbl11Rect];
lbl11.tag=1;
lbl11.font=[UIFont fontWithName:@"Superclarendon" size:15];
lbl11.backgroundColor=[UIColor clearColor];
//lbl11.layer.borderWidth = 1.0f;
[cell.contentView addSubview:lbl11];

UILabel *lbl21 = [[UILabel alloc] initWithFrame:lbl21Rect];
lbl21.tag=2;
lbl21.font=[UIFont fontWithName:@"Superclarendon" size:15];
lbl21.backgroundColor=[UIColor clearColor];
//lbl21.layer.borderWidth = 1.0f;
[cell.contentView addSubview:lbl21];

UILabel *lbl31 = [[UILabel alloc] initWithFrame:lbl31Rect];
lbl31.tag=3;
lbl31.font=[UIFont fontWithName:@"Superclarendon" size:15];
lbl31.backgroundColor=[UIColor clearColor];
//lbl31.layer.borderWidth = 1.0f;
[cell.contentView addSubview:lbl31];

cell.selectionStyle = UITableViewCellSelectionStyleBlue;
return cell;
}

对于第一个值搜索，它显示了tableview中的数据....我该如何正确更新tableview 我发现了更新

[myTable beginUpdate]

将使用

功能......还有

insertRowsAtIndexPaths: withRowAnimation

但遗憾的是没有找到任何有关如何使用它的好帮助。任何帮助将不胜感激......

Answer 1

首先更新您的数据源，以便numberOfRowsInSection和cellForRowAtIndexPath将返回插入后数据的正确值。您必须在插入或删除行之前执行此操作。然后插入你的行：

   // First figure out how many sections there are
    NSInteger lastSectionIndex = [tableView numberOfSections] - 1;

// Then grab the number of rows in the last section
NSInteger lastRowIndex = [tableView numberOfRowsInSection:lastSectionIndex];

// Now just construct the index path
NSIndexPath *pathToLastRow = [NSIndexPath indexPathForRow:lastRowIndex inSection:lastSectionIndex];

//Adding new data row to last index position:
[myTable beginUpdates];
[myTable insertRowsAtIndexPaths:[NSArray arrayWithObject: pathToLastRow] withRowAnimation:UITableViewRowAnimationNone];
[myTable endUpdates];

动画有不同的变体：

UITableViewRowAnimationBottom
UITableViewRowAnimationFade
UITableViewRowAnimationMiddle
UITableViewRowAnimationNone
UITableViewRowAnimationRight
UITableViewRowAnimationTop

来自iOs开发者库：

beginUpdates
Begin a series of method calls that insert, delete, or select rows and sections of the receiver.
Discussion
Call this method if you want subsequent insertions, deletion, and selection operations (for example, cellForRowAtIndexPath: and indexPathsForVisibleRows) to be animated simultaneously. This group of methods must conclude with an invocation of endUpdates. These method pairs can be nested. If you do not make the insertion, deletion, and selection calls inside this block, table attributes such as row count might become invalid. You should not call reloadData within the group; if you call this method within the group, you will need to perform any animations yourself.

使用此方法的示例，您可以在相关示例代码中找到： iPhoneCoreDataRecipes

tableview更新，新行保留先前的行

1 个答案: