Ios UIScrollview使用for循环水平添加子视图纯自动布局_Ios_Autolayout

Ios UIScrollview使用for循环水平添加子视图纯自动布局

ios

Ios UIScrollview使用for循环水平添加子视图纯自动布局,ios,autolayout,Ios,Autolayout,我有以下ui视图层次结构： -UIView -UIScrollView 我对UIScrollview与其超级视图的约束非常简单： @"H:|-%f-[%@]-%f-|" 及他们正在按预期工作。我正在尝试添加一个UIImageView作为scrollview水平视图的子视图。因此，我的视图层次结构将变为： -UIView -UIScrollView -UIImageView 我在uicrollview中使用for循环以编程方式将UIImageView添加为子视图在for循环中

我有以下

ui视图

层次结构：

-UIView
 -UIScrollView

我对

UIScrollview

与其超级视图的约束非常简单：

@"H:|-%f-[%@]-%f-|"

及

他们正在按预期工作。

我正在尝试添加一个

UIImageView

作为scrollview水平视图的子视图。因此，我的视图层次结构将变为：

-UIView
 -UIScrollView
  -UIImageView

我在

uicrollview

中使用

for

循环以编程方式将

UIImageView

添加为子视图

在

for

循环中，我如何实现：

[SuperView]-10-[scrollview]-10-[UIImageView]-10-[UIImageView]-10-[UIScrollView]-10-[SuperView]

有问题的部分是粗体部分。 我所尝试的：

for(int i=1;i<3;i++)
        {
            UIImageView *image = [[UIImageView alloc] init];
            [image setImage:[UIImage imageNamed:[NSString stringWithFormat:@"%d.jpg",i]]];
            image.translatesAutoresizingMaskIntoConstraints = NO;
            [_scrollView addSubview:image];

            UIView *superView = _scrollView;



            NSDictionary * views = NSDictionaryOfVariableBindings(superView, image);

            NSString *formate = [NSString stringWithFormat:@"H:|-%f-[%@]-%f-|", scrollViewLeftMarginFromParent, @"image", scrollViewRightMarginFromParent];

            NSArray * WIDTH_CONSTRAINT = [NSLayoutConstraint constraintsWithVisualFormat:formate options:0 metrics:nil views:views];

            formate = [NSString stringWithFormat:@"V:|-%f-[%@]-%f-|", scrollViewTopMarginFromParent, @"image", scrollViewBottomMarginFromParent];

            NSArray * HEIGHT_CONSTRAINT = [NSLayoutConstraint constraintsWithVisualFormat:formate options:0 metrics:nil views:views];
            [superView addConstraints:WIDTH_CONSTRAINT];
            [superView addConstraints:HEIGHT_CONSTRAINT];
        }

如果这是正确的方法，那么如何在

for

循环中实现这一点

如果不是，那么什么是最好的方法。

其实很简单。您的方法是正确的，您所需要的只是如何将其转换为代码。我会尽量为你简化这件事。我假设UIImageView的宽度和高度为100。你可以随意改变

-(void)setUI
{
    lastView = nil;   //Declare a UIImageView* as instance var.
    arrayCount = [array count]; //In your case a static count of 3

    for(NSInteger index =0; index < arrayCount; index++)
    {
        UIImageView *view = [[UIImageView alloc] init];
        [self.mainScroll addSubview:view];

        [view setTranslatesAutoresizingMaskIntoConstraints:NO];

        [self.mainScroll addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"V:|-20-[view(100)]-20-|" options:0 metrics:nil views:@{@"view":view}]];

        //--> If view is first then pin the leading edge to main ScrollView otherwise to the last View.
        if(lastView == nil && index == 0) {
            [self.mainScroll addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:|-10-[view(100)]" options:0 metrics:nil views:@{@"view":view}]];
        }
        else {
            [self.mainScroll addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:[lastView]-10-[view(100)]" options:0 metrics:nil views:@{@"lastView":lastView, @"view":view}]];
        }
        //--> If View is last then pin the trailing edge to mainScrollView trailing edge.
        if(index == arrayCount-1) {
            [self.mainScroll addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:[view]-10-|" options:0 metrics:nil views:@{@"view":view}]];
        }
        //--> Assign the current View as last view to keep the reference for next View.
        lastView = view;
    }
}

-（void）setUI
{
lastView=nil；//将UIImageView*声明为实例变量。
arrayCount=[array count]；//在本例中，静态计数为3
对于（NSInteger index=0；index如果视图是第一个视图，则将前缘固定到主滚动视图，否则固定到最后一个视图。
if（lastView==nil&&index==0）{
[self.main Scroll addConstraints:[NSLayoutConstraintsWithVisualFormat:@“H:|-10-[view（100）]选项：0度量：无视图：@{“view”：view}]]；
}
否则{
[self.main Scroll addConstraints:[NSLayoutConstraintsWithVisualFormat:@“H:[lastView]--10-[view（100）]选项：0度量：无视图：@{“lastView”：lastView，@“view”：view}]；
}
//-->如果视图是最后一个视图，则将后缘固定到主滚动视图后缘。
if（索引==arrayCount-1）{
[self.main Scroll addConstraints:[NSLayoutConstraintsWithVisualFormat:@“H:[view]--10-|”选项：0度量：无视图：@{“view”：view}]；
}
//-->将当前视图指定为最后一个视图，以保留下一个视图的参照。
lastView=视图；
}
}

-(void)setUI
{
    lastView = nil;   //Declare a UIImageView* as instance var.
    arrayCount = [array count]; //In your case a static count of 3

    for(NSInteger index =0; index < arrayCount; index++)
    {
        UIImageView *view = [[UIImageView alloc] init];
        [self.mainScroll addSubview:view];

        [view setTranslatesAutoresizingMaskIntoConstraints:NO];

        [self.mainScroll addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"V:|-20-[view(100)]-20-|" options:0 metrics:nil views:@{@"view":view}]];

        //--> If view is first then pin the leading edge to main ScrollView otherwise to the last View.
        if(lastView == nil && index == 0) {
            [self.mainScroll addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:|-10-[view(100)]" options:0 metrics:nil views:@{@"view":view}]];
        }
        else {
            [self.mainScroll addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:[lastView]-10-[view(100)]" options:0 metrics:nil views:@{@"lastView":lastView, @"view":view}]];
        }
        //--> If View is last then pin the trailing edge to mainScrollView trailing edge.
        if(index == arrayCount-1) {
            [self.mainScroll addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:[view]-10-|" options:0 metrics:nil views:@{@"view":view}]];
        }
        //--> Assign the current View as last view to keep the reference for next View.
        lastView = view;
    }
}

-（void）setUI
{
lastView=nil；//将UIImageView*声明为实例变量。
arrayCount=[array count]；//在本例中，静态计数为3
对于（NSInteger index=0；index如果视图是第一个视图，则将前缘固定到主滚动视图，否则固定到最后一个视图。
if（lastView==nil&&index==0）{
[self.main Scroll addConstraints:[NSLayoutConstraintsWithVisualFormat:@“H:|-10-[view（100）]选项：0度量：无视图：@{“view”：view}]]；
}
否则{
[self.main Scroll addConstraints:[NSLayoutConstraintsWithVisualFormat:@“H:[lastView]--10-[view（100）]选项：0度量：无视图：@{“lastView”：lastView，@“view”：view}]；
}
//-->如果视图是最后一个视图，则将后缘固定到主滚动视图后缘。
if（索引==arrayCount-1）{
[self.main Scroll addConstraints:[NSLayoutConstraintsWithVisualFormat:@“H:[view]--10-|”选项：0度量：无视图：@{“view”：view}]；
}
//-->将当前视图指定为最后一个视图，以保留下一个视图的参照。
lastView=视图；
}
}

我遇到过类似的情况，我的scrollview及其内容视图是从IB创建的，但子视图是通过编程方式添加的。为子视图编写约束使视图控制器膨胀。for循环也得到了大量的ifs和else，因此我编写了一个UIView子类来处理这个场景

在IB中更改内容视图的类类型，获取其引用，通过直接设置属性

stackViewItems

，或方法

-（void）insertStackItem:

，

-（void）insertStackItem:atIndex:

#import "IEScrollContentView.h"

@interface IEScrollContentView()
{
    NSMutableArray * _stackViewItems;
}

@property (nonatomic,strong) NSLayoutConstraint * topConstraint;
@property (nonatomic,strong) NSLayoutConstraint * bottomConstraint;

@end

@implementation IEScrollContentView

@synthesize stackViewItems = _stackViewItems;

//-----------------------------------------------------------------//
#pragma mark - Init Methods
//-----------------------------------------------------------------//

-(instancetype)initWithCoder:(NSCoder *)aDecoder {
    if(self = [super initWithCoder:aDecoder])
        _stackViewItems = [NSMutableArray new];
    return self;
}

-(instancetype)initWithFrame:(CGRect)frame {
    if(self = [super initWithFrame:frame])
        _stackViewItems = [NSMutableArray new];
    return self;
}

//-----------------------------------------------------------------//
#pragma mark - Public Methods
//-----------------------------------------------------------------//

-(void)setStackViewItems:(NSArray *)stackViewItems {
    if(!_stackViewItems)
        _stackViewItems = [NSMutableArray new];

    for (UIView * view in stackViewItems) {
        [self insertStackItem:view];
    }
}

-(void)insertStackItem:(UIView *)stackItem
{
    [self insertStackItem:stackItem atIndex:_stackViewItems.count];
}

-(void)insertStackItem:(UIView *)stackItem atIndex:(NSUInteger)index
{
    if(!stackItem || index > _stackViewItems.count)return;

    if(index == 0)
        [self addView:stackItem
            belowView:self
            aboveView:_stackViewItems.count>0?_stackViewItems.firstObject:self];

    else if(index==_stackViewItems.count)
        [self addView:stackItem
            belowView:_stackViewItems[index-1]
            aboveView:self];
    else
        [self addView:stackItem
            belowView:_stackViewItems[index-1]
            aboveView:_stackViewItems[index]];
}

//-----------------------------------------------------------------//
#pragma mark - Constraining Views
//-----------------------------------------------------------------//

-(void)addView:(UIView *)view belowView:(UIView *)viewAbove aboveView:(UIView *)viewBelow {

    view.translatesAutoresizingMaskIntoConstraints = NO;
    [self addSubview:view];

    NSArray * defaultConstraints = [NSLayoutConstraint constraintsWithVisualFormat:@"H:|-0-[view]-0-|" options:0 metrics:nil views:NSDictionaryOfVariableBindings(view)];
    NSLayoutConstraint * upperConstraint,* lowerConstraint;

    if(viewAbove==self) {
        [self removeConstraint:_topConstraint];
        upperConstraint = [NSLayoutConstraint constraintsWithVisualFormat:@"V:|-0-[view]" options:0 metrics:nil views:NSDictionaryOfVariableBindings(view)].firstObject;
        _topConstraint = upperConstraint;
    }
    else
        upperConstraint = [NSLayoutConstraint constraintsWithVisualFormat:@"V:[viewAbove]-0-[view]" options:0 metrics:nil views:NSDictionaryOfVariableBindings(view,viewAbove)].firstObject;

    if(viewBelow==self) {
        [self removeConstraint:_bottomConstraint];
        lowerConstraint = [NSLayoutConstraint constraintsWithVisualFormat:@"V:[view]-0-|" options:0 metrics:nil views:NSDictionaryOfVariableBindings(view)].firstObject;
        _bottomConstraint = lowerConstraint;
    }
    else
        lowerConstraint = [NSLayoutConstraint constraintsWithVisualFormat:@"V:[view]-0-[viewBelow]" options:0 metrics:nil views:NSDictionaryOfVariableBindings(view,viewBelow)].firstObject;

    [self addConstraints:defaultConstraints];
    [self addConstraints:@[upperConstraint,lowerConstraint]];

    [_stackViewItems addObject:view];
}

@end

我已经把文件上传到这里了

在IB中更改内容视图的类类型，获取其引用，通过直接设置属性

stackViewItems

，或方法

-（void）insertStackItem:

，

-（void）insertStackItem:atIndex:

#import "IEScrollContentView.h"

@interface IEScrollContentView()
{
    NSMutableArray * _stackViewItems;
}

@property (nonatomic,strong) NSLayoutConstraint * topConstraint;
@property (nonatomic,strong) NSLayoutConstraint * bottomConstraint;

@end

@implementation IEScrollContentView

@synthesize stackViewItems = _stackViewItems;

//-----------------------------------------------------------------//
#pragma mark - Init Methods
//-----------------------------------------------------------------//

-(instancetype)initWithCoder:(NSCoder *)aDecoder {
    if(self = [super initWithCoder:aDecoder])
        _stackViewItems = [NSMutableArray new];
    return self;
}

-(instancetype)initWithFrame:(CGRect)frame {
    if(self = [super initWithFrame:frame])
        _stackViewItems = [NSMutableArray new];
    return self;
}

//-----------------------------------------------------------------//
#pragma mark - Public Methods
//-----------------------------------------------------------------//

-(void)setStackViewItems:(NSArray *)stackViewItems {
    if(!_stackViewItems)
        _stackViewItems = [NSMutableArray new];

    for (UIView * view in stackViewItems) {
        [self insertStackItem:view];
    }
}

-(void)insertStackItem:(UIView *)stackItem
{
    [self insertStackItem:stackItem atIndex:_stackViewItems.count];
}

-(void)insertStackItem:(UIView *)stackItem atIndex:(NSUInteger)index
{
    if(!stackItem || index > _stackViewItems.count)return;

    if(index == 0)
        [self addView:stackItem
            belowView:self
            aboveView:_stackViewItems.count>0?_stackViewItems.firstObject:self];

    else if(index==_stackViewItems.count)
        [self addView:stackItem
            belowView:_stackViewItems[index-1]
            aboveView:self];
    else
        [self addView:stackItem
            belowView:_stackViewItems[index-1]
            aboveView:_stackViewItems[index]];
}

//-----------------------------------------------------------------//
#pragma mark - Constraining Views
//-----------------------------------------------------------------//

-(void)addView:(UIView *)view belowView:(UIView *)viewAbove aboveView:(UIView *)viewBelow {

    view.translatesAutoresizingMaskIntoConstraints = NO;
    [self addSubview:view];

    NSArray * defaultConstraints = [NSLayoutConstraint constraintsWithVisualFormat:@"H:|-0-[view]-0-|" options:0 metrics:nil views:NSDictionaryOfVariableBindings(view)];
    NSLayoutConstraint * upperConstraint,* lowerConstraint;

    if(viewAbove==self) {
        [self removeConstraint:_topConstraint];
        upperConstraint = [NSLayoutConstraint constraintsWithVisualFormat:@"V:|-0-[view]" options:0 metrics:nil views:NSDictionaryOfVariableBindings(view)].firstObject;
        _topConstraint = upperConstraint;
    }
    else
        upperConstraint = [NSLayoutConstraint constraintsWithVisualFormat:@"V:[viewAbove]-0-[view]" options:0 metrics:nil views:NSDictionaryOfVariableBindings(view,viewAbove)].firstObject;

    if(viewBelow==self) {
        [self removeConstraint:_bottomConstraint];
        lowerConstraint = [NSLayoutConstraint constraintsWithVisualFormat:@"V:[view]-0-|" options:0 metrics:nil views:NSDictionaryOfVariableBindings(view)].firstObject;
        _bottomConstraint = lowerConstraint;
    }
    else
        lowerConstraint = [NSLayoutConstraint constraintsWithVisualFormat:@"V:[view]-0-[viewBelow]" options:0 metrics:nil views:NSDictionaryOfVariableBindings(view,viewBelow)].firstObject;

    [self addConstraints:defaultConstraints];
    [self addConstraints:@[upperConstraint,lowerConstraint]];

    [_stackViewItems addObject:view];
}

@end

我已经把文件上传到这里了

您要求的似乎是算法修复，与

ios

或

autolayout

没有直接关系。您要求的似乎是算法修复，与

ios

或

autolayout

没有直接关系。