ios - 启用捏合以放大 View Controller

Question

我希望用户能够使用双指缩放来放大我的应用程序，该应用程序使用 Storyboard 和以编程方式生成的按钮和标签在 Viewcontroller 中生成一个 View。在 View 的属性检查器中，我选中了 User Interaction Enabled 和 Multiple Touch。但是缩放似乎不起作用。

创建 View 的重要部分的代码如下。

- (void)viewDidLoad
{
    [super viewDidLoad];
    NSInteger xPipsOrigin = 0;
    NSInteger xPipsStep = 22.0;
    NSString* cards = @"AKQJT98765432";
    NSInteger yPipsOrigin = 100;

    if (UI_USER_INTERFACE_IDIOM()== UIUserInterfaceIdiomPhone){
        xPipsOrigin = 0;
        xPipsStep = 22.0;
        xPipsStep = 34.0;

    }
    else{
        xPipsOrigin = 100;
        xPipsStep = 40.0;
    }
    NSInteger xPipsCurrent = xPipsOrigin;

    self.countCards = 0;

    self.cardList = [NSMutableArray arrayWithCapacity:0];
    yPipsOrigin = 100;
    xPipsCurrent = xPipsOrigin;

    for( int x=0;x<[cards length]; x++ ){
        [cards substringWithRange:NSMakeRange(x,1)];
        UIButton *b= [UIButton buttonWithType:UIButtonTypeRoundedRect];
        xPipsCurrent += xPipsStep;
        [b setTitle:[cards substringWithRange:NSMakeRange(x,1)] forState:UIControlStateNormal];
        [b setTitle:@" " forState:UIControlStateDisabled];
        [b setFrame:CGRectMake(xPipsCurrent, yPipsOrigin, 20, 20)];
        [b setEnabled:YES];
        [b setUserInteractionEnabled:YES];
        [self.view addSubview:b];
        [b addTarget:self action:@selector(spadeButtonPressed:) forControlEvents:UIControlEventTouchUpInside];

    }

    xPipsCurrent = xPipsOrigin + xPipsStep/2;
    for( int x=0;x<[cards length]-1; x++ ){
        xPipsCurrent += xPipsStep;
        UILabel *lab = [[UILabel alloc] initWithFrame:CGRectMake(  0, 0, 20, 20)];
        lab.text = @"\u2660";
        lab.backgroundColor = [UIColor clearColor];
        lab.center = CGPointMake(xPipsCurrent+10, yPipsOrigin+10);
        [self.view addSubview:lab];
    }

}

如何在此应用中启用双指缩放？

Answer 1

如果你想在 UIView 上启用缩放功能，你必须先将它包装到 UIScrollView 中