ios - 如何在 iOS 的 NSArray 中获取未选择的数组

Question

我正在 iOS 中使用 Objective-C 制作一款匹配游戏有一组 12 张卡片(3 列和 4 行)，它是连接到 IBOutletCollection 的 UIButton 数组，问题是当你点击第一张卡片时，你也可以同时点击其他卡牌，但允许点击的卡牌必须只有2张。如果被点击的卡片大于 1 且小于 2，如何防止卡片被点击。

Answer 1

//One action for all buttons
-(void)buttonAction:(UIButton*)button
{

//if user select three button at a time, dont do further operations
if (previousButton && currentButton) {
    return;
}

//previous button is the first button
if(previousButton==nil)
{
    previousButton=button;
}
//current button is the second button
else if(currentButton==nil)
{
    currentButton=button;
}
//if button is selected, set button as not selected and vice versa
if([button isSelected]==NO)
{
    [button setSelected:YES];
}
else
{
    [button setSelected:NO];
}
//if user press the same button again and again
if (currentButton==previousButton)
{
    currentButton=nil;
    if([previousButton isSelected]==NO)
    {
        previousButton=nil;
    }
    return;
}    
  else if((currentButton!=previousButton)&&(currentButton!=nil))
{
    //both button tags are same, that means both selected state images are same
    if(previousButton.tag==currentButton.tag)
    {
        [self performSelector:@selector(delay) withObject:nil afterDelay:0.5];
    }
    else
    {
        [self performSelector:@selector(delayTwo) withObject:nil afterDelay:0.5];
    }
 } 
 }

-(void)delay
 {
    //[currentButton setHidden:YES];
    //[previousButton setHidden:YES];
  currentButton=nil;
previousButton=nil;
score++;
NSLog(@"Score %d",score);
//the final stage, that means left only two buttons
if(score==6)
{
    //[self endGame];
  }
 } 

-(void)delayTwo
{
   [currentButton setSelected:NO];
   [previousButton setSelected:NO];
  currentButton=nil;
  previousButton=nil;
}

在 viewDidLoad 中，根据需要分配所有按钮选择和正常状态图像或标题