遍历输出所有子视图（View）

/**
*  程序获得了焦点就会自动调用这个方法(只要程序获得了焦点,所有控件才能接收触摸事件)
*/
- (void)applicationDidBecomeActive:(UIApplication *)application
{
NSString *xml = [self digView:self.window];
[xml writeToFile:@"/Users/aplle/Documents/window.xml" atomically:YES];
}

- (NSString *)digView:(UIView *)view
{
if ([view isKindOfClass:[UITableViewCell class]]) return @"";
// 1.初始化
NSMutableString *xml = [NSMutableString string];

// 2.标签开头
[xml appendFormat:@"<%@ frame=\"%@\"", view.class, NSStringFromCGRect(view.frame)];
if (!CGPointEqualToPoint(view.bounds.origin, CGPointZero)) {
[xml appendFormat:@" bounds=\"%@\"", NSStringFromCGRect(view.bounds)];
}

if ([view isKindOfClass:[UIScrollView class]]) {
UIScrollView *scroll = (UIScrollView *)view;
if (!UIEdgeInsetsEqualToEdgeInsets(UIEdgeInsetsZero, scroll.contentInset)) {
[xml appendFormat:@" contentInset=\"%@\"", NSStringFromUIEdgeInsets(scroll.contentInset)];
}
}

// 3.判断是否要结束
if (view.subviews.count == 0) {
[xml appendString:@" />"];
return xml;
} else {
[xml appendString:@">"];
}

// 4.遍历所有的子控件
for (UIView *child in view.subviews) {
NSString *childXml = [self digView:child];
[xml appendString:childXml];
}

// 5.标签结尾
[xml appendFormat:@"</%@>", view.class];

return xml;
}