Question

我正在寻找将子视图添加到视图时触发的某种委托方法。我需要这个，因为iOS7地图上的罗盘视图在它开始旋转时会被添加到mapview中（它不存在以前和未被隐藏）。但是，当我尝试操纵regionWillChangeAnimated中的罗盘视图时，它不会触发，直到用户放开地图。

基本上我需要的是： subviewWasAdded，subviewsDidChange或类似内容。

编辑：在接受Daij-Djan的建议后，我制作了MPOMapView.m和MPOMapView。

#import "MPOMapView.h"

@implementation MPOMapView

- (id)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];
    if (self) {
        // Initialization code
    }
    return self;
}

- (void)addSubview:(UIView *)view {
    [super addSubview:view];

    [self moveCompass:&view];
}


- (void)moveCompass:(UIView **)view {

    if([[[UIDevice currentDevice] systemVersion] floatValue] < 7) {
        return;
    }

    if(![*view isKindOfClass:NSClassFromString(@"MKCompassView")]) {
        return;
    }

    //Gets here
    NSLog(@"Was the compass");

    float width = (*view).frame.size.width;
    float height = (*view).frame.size.height;

    (*view).frame = CGRectMake(40, self.frame.size.height - 50, width, height);

    //Frame doesn't change
    NSLog(@"Frame should change");
}

@end

调用该方法，但框架不会更改。我也试过了：

- (void)addSubview:(UIView *)view {
    [super addSubview:view];

    [self moveCompass:view];
}


- (void)moveCompass:(UIView *)view {

    if([[[UIDevice currentDevice] systemVersion] floatValue] < 7) {
        return;
    }

    if(![view isKindOfClass:NSClassFromString(@"MKCompassView")]) {
        return;
    }

    //Gets here
    NSLog(@"Was the compass");

    float width = view.frame.size.width;
    float height = view.frame.size.height;

    view.frame = CGRectMake(40, self.frame.size.height - 50, width, height);

    //Frame doesn't change
    NSLog(@"Frame should change");
}

但这也不起作用。最后......

- (void)addSubview:(UIView *)view {
    [super addSubview:[self movedCompass:view]];
}


- (UIView *)movedCompass:(UIView *)view {

    if([[[UIDevice currentDevice] systemVersion] floatValue] < 7) {
        return view;
    }

    if(![view isKindOfClass:NSClassFromString(@"MKCompassView")]) {
        return view;
    }

    //Gets here
    NSLog(@"Was the compass");

    float width = view.frame.size.width;
    float height = view.frame.size.height;

    view.frame = CGRectMake(40, self.frame.size.height - 50, width, height);

    //Frame doesn't change
    NSLog(@"Frame should change");

    return view;
}

不起作用

Answer 1

没有这样的代表。

BUT

你所能做的只是继承MKMapView并实现insertSubview和addSubview并构建你自己的解决方案。

BUT

看到更好的方式

- (void)layoutSubviews {
    [super layoutSubviews];

                if([[[UIDevice currentDevice] systemVersion] floatValue] < 7) {
                     return;
                }

    for(id view in self.subviews) {
                if(![view isKindOfClass:NSClassFromString(@"MKCompassView")]) {
                     continue;
                }

                [self moveCompass:view]];
    }
}

- (void)moveCompass:(UIView *)view {
    //Gets here
    NSLog(@"Was the compass");

    float width = view.frame.size.width;
    float height = view.frame.size.height;

    //view.frame = CGRectMake(40, self.frame.size.height - 50, width, height);
    view.frame = CGRectMake(40, self.bounds.size.height - 50, width, height);

}

Answer 2

Daij-Djan发布了正确的答案，归功于他！

这只是我觉得代码太多的改进了：

- (void)layoutSubviews 
{
    [super layoutSubviews];

    for(id view in self.subviews) 
    {
        if([view isKindOfClass:NSClassFromString(@"MKCompassView")]) 
            [self moveCompass:view]];
    }
}

- (void)moveCompass:(UIView *)view 
{
    //change compass frame as shown by Daij-Djan
}

Answer 3

我不知道它是否会起作用，您可以尝试使用具有camera属性的mapview heading使用键值观察。

寻找subviewsDidChange委托方法

3 个答案: