我有 10 行已經在連接中想做什么添加另一個 10 行,我使用的 insertRowsAtIndexPaths,但我要的錯誤。
以下是我使用的代碼
-(void)insertDownloadedActions:(NSMutableArray *)dataToAdd
{
__weak CurrentViewController *weakSelf = self;
int64_t delayInSeconds = 2.0;
dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, delayInSeconds * NSEC_PER_SEC);
dispatch_after(popTime, dispatch_get_main_queue(), ^(void){
[weakSelf.tableView beginUpdates];
[weakSelf.dataSource addObjects:dataToAdd];
NSIndexPath *newIndexPath = [NSIndexPath indexPathForRow:[weakSelf.dataSource count]-dataToAdd.count-1 inSection:0];
[weakSelf.tableView insertRowsAtIndexPaths:@[newIndexPath] withRowAnimation:UITableViewRowAnimationTop];
[weakSelf.tableView endUpdates];
});
}
但我要為那下列錯誤
Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Invalid update: invalid number of rows in section 0. The number of rows contained in an existing section after the update (20) must be equal to the number of rows contained in that section before the update (10), plus or minus the number of rows inserted or deleted from that section (1 inserted, 0 deleted) and plus or minus the number of rows moved into or out of that section (0 moved in, 0 moved out).
解決方法 1:
代碼是密切,但表視圖需要確切的對應與什么添加到數據源中要更新的索引路徑。
-(void)insertDownloadedActions:(NSMutableArray *)dataToAdd
{
// don't need this
//__weak CurrentViewController *weakSelf = self;
int64_t delayInSeconds = 2.0;
dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, delayInSeconds * NSEC_PER_SEC);
dispatch_after(popTime, dispatch_get_main_queue(), ^(void) {
// build the index paths for insertion
// since you're adding to the end of datasource, the new rows will start at count
NSMutableArray *indexPaths = [NSMutableArray array];
NSInteger currentCount = self.datasource.count;
for (int i = 0; i < dataToAdd.count; i++) {
[indexPaths addObject:[NSIndexPath indexPathForRow:currentCount+i inSection:0]];
}
// do the insertion
[self.dataSource addObjects:dataToAdd];
// tell the table view to update (at all of the inserted index paths)
[self.tableView beginUpdates];
[self.tableView insertRowsAtIndexPaths:indexPaths withRowAnimation:UITableViewRowAnimationTop];
[self.tableView endUpdates];
});
}
你想要避免周期哪里塊所有者保留塊和塊 weakSelf (通過使用塊所有者"自我") 保留所有者。有的 weakSelf 模式在這里沒有必要因為視圖控制器不保留在被派遣的塊的副本。