我知道Apple文档没有指定cellForRowAtIndexPath按顺序排列，即首先它将转到第0部分，索引0;然后是第0节，索引2;然后是第1节，索引0 ......等等。我认为它跳了起来。
下面有什么更好的方法来实现？目前我一直收到错误
NSRangeException', reason: '*** -[__NSArrayM objectAtIndex:]: index 3 beyond bounds [0 .. 2]'
错误出现b / c我认为cellForRowAtIndexPath会跳转并标记
*sectioned = NULL，因此跳过条件并通过转到错误的条件转到空数组或超过索引计数。
以下是代码：
... declared and synthesized
NSManaged *object;
@property (strong, nonatomic) NSNumber *sevenDaysSectionFilled;
@property (strong, nonatomic) NSNumber *fourteenDaysSectionFilled;
@property (strong, nonatomic) NSNumber *thirtyDaysSectionFilled;
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
object = NULL;
static NSString *CellIdentifier = @"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];
if (indexPath.section == 0)
{
if ((SevenDaysArraySectioned == [NSNumber numberWithBool:YES]) && (sevenDaysSectionFilled != [NSNumber numberWithBool:YES]))
{
object = [pastSevenDayArray objectAtIndex:indexPath.row];
sevenDaysSectionFilled = [NSNumber numberWithBool:YES];
}
else if ((fourteenDaysArraySectioned == [NSNumber numberWithBool:YES]) && (fourteenDaysSectionFilled != [NSNumber numberWithBool:YES]))
{
object = [pastFourteenDaysArray objectAtIndex:indexPath.row];
fourteenDaysSectionFilled = [NSNumber numberWithBool:YES];
}
else if ((thirtyDaysArraySectioned == [NSNumber numberWithBool:YES]) && (thirtyDaysSectionFilled != [NSNumber numberWithBool:YES]))
{
object = [pastThirtyDaysArray objectAtIndex:indexPath.row];
thirtyDaysSectionFilled = [NSNumber numberWithBool:YES];
}
else if (indexPath.section == 1)
{
if ((fourteenDaysArraySectioned == [NSNumber numberWithBool:YES]) && (fourteenDaysSectionFilled != [NSNumber numberWithBool:YES]))
{
object = [pastFourteenDaysArray objectAtIndex:indexPath.row];
fourteenDaysSectionFilled = [NSNumber numberWithBool:YES];
}
else if ((thirtyDaysArraySectioned == [NSNumber numberWithBool:YES]) && (thirtyDaysSectionFilled != [NSNumber numberWithBool:YES]))
{
object = [pastThirtyDaysArray objectAtIndex:indexPath.row];
thirtyDaysSectionFilled = [NSNumber numberWithBool:YES];
}
else if (indexPath.section == 2)
{
if ((thirtyDaysArraySectioned == [NSNumber numberWithBool:YES]) && (thirtyDaysSectionFilled != [NSNumber numberWithBool:YES]))
{
object = [pastThirtyDaysArray objectAtIndex:indexPath.row];
thirtyDaysSectionFilled = [NSNumber numberWithBool:YES];
}
}
NSString *entityName = [[object entity]name];
cell.textLabel.text = [NSString stringWithFormat:@"%@ %i", entityName, [indexPath row]];
object = NULL;
return cell;
}
如果有更好的方法可以告诉我。谢谢。
*的修改
这有点复杂，但现在是：
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
numberOfSections = 0;
if ([pastSevenDayArray count] > 0) numberOfSections++;
if ([pastFourteenDaysArray count] > 0) numberOfSections++;
if ([pastThirtyDaysArray count] > 0) numberOfSections++;
if ([pastSixtyDaysArray count] > 0) numberOfSections++;
if ([pastNinteyDaysArray count] > 0) numberOfSections++;
if ([pastArray count] > 0) numberOfSections++;
[self numberOfCells];
return numberOfSections;
}
numberOfCells
-(void)numberOfCells
{
for (int section = 0; section<numberOfSections; section ++)
{
if (section == 0)
{
if ([pastSevenDayArray count] > 0)
{
SevenDaysArraySectioned = [NSNumber numberWithBool:YES];
sectionZeroCellCount = [pastSevenDayArray count];
sectionZeroHeader = sevenDaysSectionLabel;
}
else if ([pastFourteenDaysArray count] > 0)
{
fourteenDaysArraySectioned = [NSNumber numberWithBool:YES];
sectionZeroCellCount = [pastFourteenDaysArray count];
sectionZeroHeader = fourteenDaysSectionLabel;
}
else if ([pastThirtyDaysArray count] > 0)
{
thirtyDaysArraySectioned = [NSNumber numberWithBool:YES];
sectionZeroCellCount = [pastThirtyDaysArray count];
sectionZeroHeader = thirtyDaysSectionLabel;
}
else if ([pastSixtyDaysArray count] > 0)
{
sixtyDaysArraySectioned = [NSNumber numberWithBool:YES];
sectionZeroCellCount = [pastSixtyDaysArray count];
sectionZeroHeader = sixtyDaysSectionLabel;
}
else if ([pastNinteyDaysArray count] > 0)
{
ninetyDaysArraySectioned = [NSNumber numberWithBool:YES];
sectionZeroCellCount = [pastNinteyDaysArray count];
sectionZeroHeader = ninetyDaysSectionLabel;
}
else if ([pastArray count] > 0)
{
pastArraySectioned = [NSNumber numberWithBool:YES];
sectionZeroCellCount = [pastArray count];
sectionZeroHeader = pastSectionLabel;
}
}
else if (section == 1)
{
if (([pastFourteenDaysArray count] > 0) && (fourteenDaysArraySectioned != [NSNumber numberWithBool:YES]))
{
fourteenDaysArraySectioned = [NSNumber numberWithBool:YES];
sectionOneCellCount = [pastFourteenDaysArray count];
sectionOneHeader = fourteenDaysSectionLabel;
}
else if (([pastThirtyDaysArray count] > 0) && (thirtyDaysArraySectioned != [NSNumber numberWithBool:YES]))
{
thirtyDaysArraySectioned = [NSNumber numberWithBool:YES];
sectionOneCellCount = [pastThirtyDaysArray count];
sectionOneHeader = thirtyDaysSectionLabel;
}
else if (([pastSixtyDaysArray count] > 0) && (sixtyDaysArraySectioned != [NSNumber numberWithBool:YES]))
{
sixtyDaysArraySectioned = [NSNumber numberWithBool:YES];
sectionOneCellCount = [pastSixtyDaysArray count];
sectionOneHeader = sixtyDaysSectionLabel;
}
else if (([pastNinteyDaysArray count] > 0) && (ninetyDaysArraySectioned != [NSNumber numberWithBool:YES]))
{
ninetyDaysArraySectioned = [NSNumber numberWithBool:YES];
sectionOneCellCount = [pastNinteyDaysArray count];
sectionOneHeader = ninetyDaysSectionLabel;
}
else if (([pastArray count] > 0) && (pastArraySectioned != [NSNumber numberWithBool:YES]))
{
pastArraySectioned = [NSNumber numberWithBool:YES];
sectionOneCellCount = [pastArray count];
sectionOneHeader = pastSectionLabel;
}
}
else if (section ==2)
{
if (([pastThirtyDaysArray count] > 0) && (thirtyDaysArraySectioned != [NSNumber numberWithBool:YES]))
{
thirtyDaysArraySectioned = [NSNumber numberWithBool:YES];
sectionTwoCellCount = [pastThirtyDaysArray count];
sectionTwoHeader = thirtyDaysSectionLabel;
}
else if (([pastSixtyDaysArray count] > 0) && (sixtyDaysArraySectioned != [NSNumber numberWithBool:YES]))
{
sixtyDaysArraySectioned = [NSNumber numberWithBool:YES];
sectionTwoCellCount = [pastSixtyDaysArray count];
sectionTwoHeader = sixtyDaysSectionLabel;
}
else if (([pastNinteyDaysArray count] > 0) && (ninetyDaysArraySectioned != [NSNumber numberWithBool:YES]))
{
ninetyDaysArraySectioned = [NSNumber numberWithBool:YES];
sectionTwoCellCount = [pastNinteyDaysArray count];
sectionTwoHeader = ninetyDaysSectionLabel;
}
else if (([pastArray count] > 0) && (pastArraySectioned != [NSNumber numberWithBool:YES]))
{
pastArraySectioned = [NSNumber numberWithBool:YES];
sectionTwoCellCount = [pastArray count];
sectionTwoHeader = pastSectionLabel;
}
}
else if (section ==3)
{
NSLog(@"Entered Section %i", section);
if (([pastSixtyDaysArray count] > 0) && (sixtyDaysArraySectioned != [NSNumber numberWithBool:YES])) {
sixtyDaysArraySectioned = [NSNumber numberWithBool:YES];
sectionThreeCellCount = [pastSixtyDaysArray count];
sectionThreeHeader = sixtyDaysSectionLabel;
}
else if (([pastNinteyDaysArray count] > 0) && (ninetyDaysArraySectioned != [NSNumber numberWithBool:YES]))
{
ninetyDaysArraySectioned = [NSNumber numberWithBool:YES];
sectionThreeCellCount = [pastNinteyDaysArray count];
sectionThreeHeader = ninetyDaysSectionLabel;
}
else if (([pastArray count] > 0) && (pastArraySectioned != [NSNumber numberWithBool:YES]))
{
pastArraySectioned = [NSNumber numberWithBool:YES];
sectionThreeCellCount = [pastArray count];
sectionThreeHeader = pastSectionLabel;
}
}
else if (section ==4)
{
NSLog(@"Entered Section %i", section);
if (([pastNinteyDaysArray count] > 0) && (ninetyDaysArraySectioned != [NSNumber numberWithBool:YES]))
{
ninetyDaysArraySectioned = [NSNumber numberWithBool:YES];
sectionFourCellCount = [pastNinteyDaysArray count];
sectionFourHeader = ninetyDaysSectionLabel;
}
else if (([pastArray count] > 0) && (pastArraySectioned != [NSNumber numberWithBool:YES]))
{
pastArraySectioned = [NSNumber numberWithBool:YES];
sectionFourCellCount = [pastArray count];
sectionFourHeader = pastSectionLabel;
}
}
else if (section ==5)
{
NSLog(@"Entered Section %i", section);
if (([pastArray count] > 0) && (pastArraySectioned != [NSNumber numberWithBool:YES]))
{
pastArraySectioned = [NSNumber numberWithBool:YES];
sectionFiveCellCount = [pastArray count];
sectionFiveHeader = pastSectionLabel;
}
}
}
}
numberOfRowsInSection
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
if (section == 0)
{
return sectionZeroCellCount;
}
else if (section == 1)
{
return sectionOneCellCount;
}
else if (section == 2)
{
return sectionTwoCellCount;
}
else if (section == 3)
{
return sectionThreeCellCount;
}
else if (section == 4)
{
return sectionFourCellCount;
}
if (section == 5)
{
return sectionFiveCellCount;
}
}
编辑2
标题：
- (CGFloat)tableView:(UITableView *)tableView heightForHeaderInSection:(NSInteger)section
{
return 30.0;
}
- (UIView *) tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger)section
{
UIView *headerView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, tableView.bounds.size.width, 150)];
UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(10, 3, tableView.bounds.size.width - 10, 25)];
label.backgroundColor = [UIColor clearColor];
[label setFont:[UIFont boldSystemFontOfSize:16]];
label.textColor = [UIColor whiteColor];
if (section == 0)
{
label.text = sectionZeroHeader;
}
else if (section == 1)
{
label.text = sectionOneHeader;
}
else if (section == 2)
{
label.text = sectionTwoHeader;
}
else if (section == 3)
{
label.text = sectionThreeHeader;
}
else if (section == 4)
{
label.text = sectionFourHeader;
}
else if (section == 5)
{
label.text = sectionFiveHeader;
}
[headerView addSubview:label];
return headerView;
}
答案 0 :(得分：1)
我认为你必须确定你设置了适当的
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section;
和
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView;
如果你想拥有多个部分，并且每个部分都有很多行，请使用NSDictionary并设置密钥 - ＆gt;数组值，然后
NSDictionary *dict = @{@"section1": @[@"obj1", @"obj2"],@"section2": @[@"obj3", @"obj4"]};
NSInteger numberOfSections = [[dict allKeys] count];// return in numberOfSections
NSArray *values = [dict valueForKey:@"obj1"];// get appropriate array
答案 1 :(得分：1)
在各种实例变量中维护了很多状态，而不是必须的。我们可以使用集合和其他数据结构来构建表应该如何定义，然后在我们的数据源/委托方法中引用它。
此视图控制器的基本思想是每个部分由CVSectionModel对象表示，该对象包含该部分的行数据，以及特定于部分的信息，如标题视图。在viewDidLoad内部，我们构建了这些剖面模型，每当我们完成数据更新时，我们都应该重新构建它们。要尝试使用不同的数据安排，请使用其他测试方法之一将viewDidLoad中的调用替换为testCase1。
我们维护一系列剖面模型，只有在有内容显示的情况下才为剖面创建模型。正如您所看到的，这简化了用于获取行信息的数组的计算以及每个部分中的行数。我们只是向section模型询问一个部分该做什么，而不是同步几个不同的实例变量。
请注意，此表控制器不支持更精细的内容插入，删除或重新排序动画，因此如果需要，则需要额外的工作。但它确实支持在更新后重新加载常规表，如在viewDidLoad之后10秒运行的块中可以看到的。
请检查代码并提出任何问题。这是实现文件，但除了@interface CVViewController: UIViewController @end之外，标题中没有任何内容。
@interface CVSectionModel : NSObject
@property (nonatomic) NSArray *rowModels;
@property (nonatomic) NSString *sectionTitle;
@property (nonatomic) NSInteger tag; // possibly useful for animations, different behavior on section, etc.
@end
@implementation CVSectionModel
@end
@interface CVViewController () <UITableViewDataSource, UITableViewDelegate>
@property (weak, nonatomic) IBOutlet UITableView *tableView;
@property (nonatomic) NSArray *sectionModels;
@property (nonatomic) NSArray *sevenDays;
@property (nonatomic) NSArray *fourteenDays;
@property (nonatomic) NSArray *thirtyDays;
@end
@implementation CVViewController
- (void)viewDidLoad
{
[super viewDidLoad];
// In your application, you'll be loading and processing your real data
// But here I'm just going to simulate a number of cases with strings for illustration
// Call the other methods to try different configurations
[self testCase1];
// We call this once on viewDidLoad. You'll also want to call it whenever you update the underlying data, as in the block below
[self processSectionData];
[self.tableView registerClass:[UITableViewCell class] forCellReuseIdentifier:@"IDENTIFIER"];
// Demonstrate support for modifying the underlying data and refresh the view.
// Uncomment to test it.
// double delayInSeconds = 10.0;
// dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, (int64_t)(delayInSeconds * NSEC_PER_SEC));
// dispatch_after(popTime, dispatch_get_main_queue(), ^(void){
// [self testCase2];
// [self processSectionData];
// [self.tableView reloadData];
// });
}
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
return [self.sectionModels count];
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
return [((CVSectionModel *)self.sectionModels[section]).rowModels count];
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"IDENTIFIER"];
// In your app this appears to be an NSManagedObject of some type, here it's just a string
NSString *modelForRow = ((CVSectionModel *)self.sectionModels[indexPath.section]).rowModels[indexPath.row];
cell.textLabel.text = modelForRow;
return cell;
}
- (CGFloat)tableView:(UITableView *)tableView heightForHeaderInSection:(NSInteger)section
{
return 30.0;
}
- (UIView *)tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger)section
{
NSString *sectionTitle = ((CVSectionModel *)self.sectionModels[section]).sectionTitle;
UIView *headerView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, tableView.bounds.size.width, 150)];
UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(10, 3, tableView.bounds.size.width - 10, 25)];
label.backgroundColor = [UIColor clearColor];
[label setFont:[UIFont boldSystemFontOfSize:16]];
label.textColor = [UIColor whiteColor];
label.text = sectionTitle;
[headerView addSubview:label];
return headerView;
}
- (void)processSectionData
{
NSArray *allDayArrays = @[self.sevenDays, self.fourteenDays, self.thirtyDays];
// You won't use hard-coded strings here - use your sevenDaysSectionLabel, etc. variables instead
NSArray *labelTitles = @[@"7 days", @"14 days", @"30 days"];
NSMutableArray *mutableSectionModels = [NSMutableArray array];
[allDayArrays enumerateObjectsUsingBlock:^(NSArray *array, NSUInteger index, BOOL *stop) {
if ([array count] > 0) {
CVSectionModel *sectionModel = [[CVSectionModel alloc] init];
sectionModel.rowModels = array;
sectionModel.sectionTitle = labelTitles[index];
sectionModel.tag = index+1; // track this to enable re-ordering in the future
[mutableSectionModels addObject:sectionModel];
}
}];
// If Animating insertions / deletions will require something more elaborate
self.sectionModels = [mutableSectionModels copy];
}
// Case 1:
// All three populated
- (void)testCase1
{
self.sevenDays = @[@"sevendayitem1", @"sevendayitem2", @"sevendayitem3", @"sevendayitem4"];
self.fourteenDays = @[@"14day item 1", @"14 day item 2"];
self.thirtyDays = @[@"30 day item 1", @"30 day item 2", @"30 day item 3"];
}
// Case 2:
// self.fourteenDays is empty
- (void)testCase2
{
self.sevenDays = @[@"sevendayitem1", @"sevendayitem2", @"sevendayitem3", @"sevendayitem4"];
self.fourteenDays = @[];
self.thirtyDays = @[@"30 day item 1", @"30 day item 2", @"30 day item 3"];
}
// Case 3:
// self.thirtydays is the only one
- (void)testCase3
{
self.sevenDays = @[];
self.fourteenDays = @[];
self.thirtyDays = @[@"30 day item 1", @"30 day item 2", @"30 day item 3"];
}
@end