OC小结

禁止第三方输入键盘

//禁止第三方输入键盘
- (BOOL)application:(UIApplication *)application shouldAllowExtensionPointIdentifier:(NSString *)extensionPointIdentifier {
    return NO;
}

行数算法

//行数
NSInteger row = (self.btnArr.count + colNum - 1) / colNum;

九宫格算法

-(void)layoutSubviews{
    [super layoutSubviews];
    //设置按钮的frame值
    //计算处在哪行哪列
    for (int i = 0; i < self.btnArr.count; ++i) {
        
        NSInteger col = i % colNum;
        NSInteger row = i / colNum;
        
        CGFloat btnX = padding + col * (tangButtonW + margin);
        CGFloat btnY = 44 + padding + row * (tangButtonH + margin);
        //设置按钮的frame值
        UIButton *btn = self.btnArr[i];
        btn.frame = CGRectMake(btnX, btnY, tangButtonW, tangButtonH);
    }
}

处理连点

[[self class] cancelPreviousPerformRequestsWithTarget:self selector:@selector(todoSomething:) object:btn];
[self performSelector:@selector(todoSomething:) withObject:btn afterDelay:0.2f];

IMP类型(就是实现方法) 来源：UITableView-FDTemplateLayoutCell-master

- (IBAction)rightNavigationItemAction:(id)sender {
    [[[UIActionSheet alloc]
      initWithTitle:@"Actions"
      delegate:self
      cancelButtonTitle:@"Cancel"
      destructiveButtonTitle:nil
      otherButtonTitles:
      @"Insert a row",
      @"Insert a section",
      @"Delete a section", nil]
     showInView:self.view];
}

- (void)actionSheet:(UIActionSheet *)actionSheet clickedButtonAtIndex:(NSInteger)buttonIndex {
    SEL selectors[] = {
        @selector(insertRow),
        @selector(insertSection),
        @selector(deleteSection)
    };

    if (buttonIndex < sizeof(selectors) / sizeof(SEL)) {
        //定义IMP类型，IMP类型就是实现方法
        void(*imp)(id, SEL) = (typeof(imp))[self methodForSelector:selectors[buttonIndex]];
        imp(self, selectors[buttonIndex]);
    }
}

- (FDFeedEntity *)randomEntity {
    NSUInteger randomNumber = arc4random_uniform((int32_t)self.prototypeEntitiesFromJSON.count);
    FDFeedEntity *randomEntity = self.prototypeEntitiesFromJSON[randomNumber];
    return randomEntity;
}

- (void)insertRow {
    if (self.feedEntitySections.count == 0) {
        [self insertSection];
    } else {
        [self.feedEntitySections[0] insertObject:self.randomEntity atIndex:0];
        NSIndexPath *indexPath = [NSIndexPath indexPathForRow:0 inSection:0];
        [self.tableView insertRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationAutomatic];
    }
}

- (void)insertSection {
    [self.feedEntitySections insertObject:@[self.randomEntity].mutableCopy atIndex:0];
    [self.tableView insertSections:[NSIndexSet indexSetWithIndex:0] withRowAnimation:UITableViewRowAnimationAutomatic];
}

- (void)deleteSection {
    if (self.feedEntitySections.count > 0) {
        [self.feedEntitySections removeObjectAtIndex:0];
        [self.tableView deleteSections:[NSIndexSet indexSetWithIndex:0] withRowAnimation:UITableViewRowAnimationAutomatic];
    }
}