发表于(2016-09-27 16:35:49)

最近项目到某个节点，我在解决一些问题的时候，记录一下：

1. RAC 在引用的时候会忽略一点，如
   @weakify(self); @weakify(cell); [[[cell.clearButton rac_signalForControlEvents:UIControlEventTouchUpInside] takeUntil:cell.rac_prepareForReuseSignal] subscribeNext:^(UIButton *x) { if ([self_weak_.selectedNumArray containsObject:asset]) { [self_weak_.selectedNumArray removeObject:asset]; cell_weak_.numButton.selected = NO; [self_weak_.collectionView reloadData]; }else{ if (self_weak_.addMorePicture) { if (self_weak_.selectedNumArray.count==self_weak_.maxPictureCanAdd) { LxDBAnyVar(self_weak_.selectedNumArray); LxDBAnyVar(self_weak_.maxPictureCanAdd); [SHUIHelper showAlertMessage:[NSString stringWithFormat:@"您最多可添加%ld张哦",self_weak_.maxPictureCanAdd]]; }else{ [self_weak_.selectedNumArray addObject:asset]; cell_weak_.numButton.selected = YES; [cell_weak_.numButton setTitle:[NSString stringWithFormat:@"%ld",(unsigned long)self_weak_.selectedNumArray.count] forState:UIControlStateNormal]; } }else{ if (self_weak_.selectedNumArray.count==6) { [SHUIHelper showAlertMessage:@"选取最多6张"]; }else{ [self_weak_.selectedNumArray addObject:asset]; cell_weak_.numButton.selected = YES; [cell_weak_.numButton setTitle:[NSString stringWithFormat:@"%ld",(unsigned long)self_weak_.selectedNumArray.count] forState:UIControlStateNormal]; } } } cell_weak_.grayLayerView.hidden = !cell_weak_.numButton.selected; }];
   上面这里的cell，自己对自己进行了循环引用，原因就是：这一段如果写在该Cell class里面，那么block里面的cell，其实在自身类里面也叫self，于是也需要进行weak处理。
   这里会出现这样的错误，就是因为写得太快了，然后有时候会想不出来，可以慢慢思考。
2. Realm 的RLMArray 如果添加某一个元素，但其已经存在数据库中，那么做法是先使用[RLMObject objectForPrimaryKey：@“keyID”]找出该元素添加进去，即可

   Just want to add a comment for future users of Realm. I think TiM means[ objectForPrimaryKey:…]. I literally typed [RLMObject objectForPrimaryKey:…] and got a crash about “RLMObject” is not persisted in Realm database