Ios 为什么我的方法调用两次?
我在我的页面视图控制器类中有一个方法,它意味着一次生成一组数字,但由于某种原因它似乎触发了两次?有人能告诉我为什么它发射了两次吗 这是控制台激发的 发生了什么,为什么它不能正常工作 我希望我的页面视图控制器在用户向前滚动时循环,而我有五个不同的数字,它们在同一时间不断上升,但不循环,它们只是无限增加 向后滑动法Ios 为什么我的方法调用两次?,ios,objective-c,uipageviewcontroller,Ios,Objective C,Uipageviewcontroller,我在我的页面视图控制器类中有一个方法,它意味着一次生成一组数字,但由于某种原因它似乎触发了两次?有人能告诉我为什么它发射了两次吗 这是控制台激发的 发生了什么,为什么它不能正常工作 我希望我的页面视图控制器在用户向前滚动时循环,而我有五个不同的数字,它们在同一时间不断上升,但不循环,它们只是无限增加 向后滑动法 -(UIViewController *)pageViewController:(UIPageViewController *)pageViewController view
-(UIViewController *)pageViewController:(UIPageViewController *)pageViewController
viewControllerBeforeViewController:(UIViewController *)viewController
{
NSUInteger currentIndex = [myViewControllers indexOfObject:viewController];
swipeTotal = swipeTotal - 1;
if (swipeTotal > 4) {
firstFive = true;
// NSLog(@"First Five Passed");
}else{
firstFive = false;
// NSLog(@"First Five False");
}
// NSLog(@"Swipe Total is %d",swipeTotal);
if (currentIndex == 0) {
swipeContent1 = swipeTotal;
swipeContent2 = swipeTotal + 1;
swipeContent3 = swipeTotal + 2;
swipeContent4 = swipeTotal - 2;
swipeContent5 = swipeTotal - 1;
}
if (currentIndex == 1) {
swipeContent1 = swipeTotal - 1;
swipeContent2 = swipeTotal;
swipeContent3 = swipeTotal + 1;
swipeContent4 = swipeTotal + 2;
swipeContent5 = swipeTotal - 2;
}
if (currentIndex == 2) {
swipeContent1 = swipeTotal - 2;
swipeContent2 = swipeTotal - 1;
swipeContent3 = swipeTotal;
swipeContent4 = swipeTotal + 1;
swipeContent5 = swipeTotal + 2;
}
if (currentIndex == 3) {
swipeContent1 = swipeTotal + 2;
swipeContent2 = swipeTotal - 2;
swipeContent3 = swipeTotal - 1;
swipeContent4 = swipeTotal;
swipeContent5 = swipeTotal + 1;
}
if (currentIndex == 4) {
swipeContent1 = swipeTotal + 1;
swipeContent2 = swipeTotal + 2;
swipeContent3 = swipeTotal - 2;
swipeContent4 = swipeTotal - 1;
swipeContent5 = swipeTotal;
}
if (firstFive == true) {
if (currentIndex == 0) {
currentIndex = 4;
}else{
--currentIndex;
currentIndex = currentIndex % (myViewControllers.count);
}
}else{
if (currentIndex > 0)
{
return [myViewControllers objectAtIndex:currentIndex-1];
// return the previous viewcontroller
} else
{
return nil;
// do nothing
}
}
/*
content1 = [users objectAtIndex:swipeContent1];
content2 = [users objectAtIndex:swipeContent2];
content3 = [users objectAtIndex:swipeContent3];
content4 = [users objectAtIndex:swipeContent4];
content5 = [users objectAtIndex:swipeContent5]; */
NSLog(@"Content 1 = %d",swipeContent1);
NSLog(@"Content 2 = %d",swipeContent2);
NSLog(@"Content 3 = %d",swipeContent3);
NSLog(@"Content 4 = %d",swipeContent4);
NSLog(@"Content 5 = %d",swipeContent5);
return [myViewControllers objectAtIndex:currentIndex];
}
-(UIViewController *)pageViewController:(UIPageViewController *)pageViewController
viewControllerAfterViewController:(UIViewController *)viewController
{
NSUInteger currentIndex = [myViewControllers indexOfObject:viewController];
if (swipeTotal > 4) {
firstFive = true;
// NSLog(@"First Five Passed");
}else{
firstFive = false;
// NSLog(@"First Five False");
}
// NSLog(@"Swipe Total is %d",swipeTotal);
++currentIndex;
currentIndex = currentIndex % (myViewControllers.count);
swipeTotal = swipeTotal + 1;
if (currentIndex == 0) {
swipeContent1 = swipeTotal;
swipeContent2 = swipeTotal + 1;
swipeContent3 = swipeTotal + 2;
swipeContent4 = swipeTotal - 2;
swipeContent5 = swipeTotal - 1;
} else if (currentIndex == 1) {
swipeContent1 = swipeTotal - 1;
swipeContent2 = swipeTotal;
swipeContent3 = swipeTotal + 1;
swipeContent4 = swipeTotal + 2;
swipeContent5 = swipeTotal - 2;
} else if (currentIndex == 2) {
swipeContent1 = swipeTotal - 2;
swipeContent2 = swipeTotal - 1;
swipeContent3 = swipeTotal;
swipeContent4 = swipeTotal + 1;
swipeContent5 = swipeTotal + 2;
} else if (currentIndex == 3) {
swipeContent1 = swipeTotal + 2;
swipeContent2 = swipeTotal - 2;
swipeContent3 = swipeTotal - 1;
swipeContent4 = swipeTotal;
swipeContent5 = swipeTotal + 1;
} else if (currentIndex == 4) {
swipeContent1 = swipeTotal + 1;
swipeContent2 = swipeTotal + 2;
swipeContent3 = swipeTotal - 2;
swipeContent4 = swipeTotal - 1;
swipeContent5 = swipeTotal;
}
NSLog(@"Content 1 = %d",swipeContent1);
NSLog(@"Content 2 = %d",swipeContent2);
NSLog(@"Content 3 = %d",swipeContent3);
NSLog(@"Content 4 = %d",swipeContent4);
NSLog(@"Content 5 = %d",swipeContent5);
return [myViewControllers objectAtIndex:currentIndex];
}
向前滑动法
-(UIViewController *)pageViewController:(UIPageViewController *)pageViewController
viewControllerBeforeViewController:(UIViewController *)viewController
{
NSUInteger currentIndex = [myViewControllers indexOfObject:viewController];
swipeTotal = swipeTotal - 1;
if (swipeTotal > 4) {
firstFive = true;
// NSLog(@"First Five Passed");
}else{
firstFive = false;
// NSLog(@"First Five False");
}
// NSLog(@"Swipe Total is %d",swipeTotal);
if (currentIndex == 0) {
swipeContent1 = swipeTotal;
swipeContent2 = swipeTotal + 1;
swipeContent3 = swipeTotal + 2;
swipeContent4 = swipeTotal - 2;
swipeContent5 = swipeTotal - 1;
}
if (currentIndex == 1) {
swipeContent1 = swipeTotal - 1;
swipeContent2 = swipeTotal;
swipeContent3 = swipeTotal + 1;
swipeContent4 = swipeTotal + 2;
swipeContent5 = swipeTotal - 2;
}
if (currentIndex == 2) {
swipeContent1 = swipeTotal - 2;
swipeContent2 = swipeTotal - 1;
swipeContent3 = swipeTotal;
swipeContent4 = swipeTotal + 1;
swipeContent5 = swipeTotal + 2;
}
if (currentIndex == 3) {
swipeContent1 = swipeTotal + 2;
swipeContent2 = swipeTotal - 2;
swipeContent3 = swipeTotal - 1;
swipeContent4 = swipeTotal;
swipeContent5 = swipeTotal + 1;
}
if (currentIndex == 4) {
swipeContent1 = swipeTotal + 1;
swipeContent2 = swipeTotal + 2;
swipeContent3 = swipeTotal - 2;
swipeContent4 = swipeTotal - 1;
swipeContent5 = swipeTotal;
}
if (firstFive == true) {
if (currentIndex == 0) {
currentIndex = 4;
}else{
--currentIndex;
currentIndex = currentIndex % (myViewControllers.count);
}
}else{
if (currentIndex > 0)
{
return [myViewControllers objectAtIndex:currentIndex-1];
// return the previous viewcontroller
} else
{
return nil;
// do nothing
}
}
/*
content1 = [users objectAtIndex:swipeContent1];
content2 = [users objectAtIndex:swipeContent2];
content3 = [users objectAtIndex:swipeContent3];
content4 = [users objectAtIndex:swipeContent4];
content5 = [users objectAtIndex:swipeContent5]; */
NSLog(@"Content 1 = %d",swipeContent1);
NSLog(@"Content 2 = %d",swipeContent2);
NSLog(@"Content 3 = %d",swipeContent3);
NSLog(@"Content 4 = %d",swipeContent4);
NSLog(@"Content 5 = %d",swipeContent5);
return [myViewControllers objectAtIndex:currentIndex];
}
-(UIViewController *)pageViewController:(UIPageViewController *)pageViewController
viewControllerAfterViewController:(UIViewController *)viewController
{
NSUInteger currentIndex = [myViewControllers indexOfObject:viewController];
if (swipeTotal > 4) {
firstFive = true;
// NSLog(@"First Five Passed");
}else{
firstFive = false;
// NSLog(@"First Five False");
}
// NSLog(@"Swipe Total is %d",swipeTotal);
++currentIndex;
currentIndex = currentIndex % (myViewControllers.count);
swipeTotal = swipeTotal + 1;
if (currentIndex == 0) {
swipeContent1 = swipeTotal;
swipeContent2 = swipeTotal + 1;
swipeContent3 = swipeTotal + 2;
swipeContent4 = swipeTotal - 2;
swipeContent5 = swipeTotal - 1;
} else if (currentIndex == 1) {
swipeContent1 = swipeTotal - 1;
swipeContent2 = swipeTotal;
swipeContent3 = swipeTotal + 1;
swipeContent4 = swipeTotal + 2;
swipeContent5 = swipeTotal - 2;
} else if (currentIndex == 2) {
swipeContent1 = swipeTotal - 2;
swipeContent2 = swipeTotal - 1;
swipeContent3 = swipeTotal;
swipeContent4 = swipeTotal + 1;
swipeContent5 = swipeTotal + 2;
} else if (currentIndex == 3) {
swipeContent1 = swipeTotal + 2;
swipeContent2 = swipeTotal - 2;
swipeContent3 = swipeTotal - 1;
swipeContent4 = swipeTotal;
swipeContent5 = swipeTotal + 1;
} else if (currentIndex == 4) {
swipeContent1 = swipeTotal + 1;
swipeContent2 = swipeTotal + 2;
swipeContent3 = swipeTotal - 2;
swipeContent4 = swipeTotal - 1;
swipeContent5 = swipeTotal;
}
NSLog(@"Content 1 = %d",swipeContent1);
NSLog(@"Content 2 = %d",swipeContent2);
NSLog(@"Content 3 = %d",swipeContent3);
NSLog(@"Content 4 = %d",swipeContent4);
NSLog(@"Content 5 = %d",swipeContent5);
return [myViewControllers objectAtIndex:currentIndex];
}
我认为您的
UIPageViewController
需要3个控制器(通常)才能正确显示其内容:
因此,这两种方法不会分别针对滑动方向调用,而是在每次滚动控制器时调用。因此,您的刷卡内容将被评估两次。为这两个方法添加一个断点,然后查看调用它们的内容。