i want a game that scrolls the background in a similar way to a UItableView. I solved it with a timer that moves the background up and brings another copy of the same picture up
if (bg1.center.y <= - self.view.bounds.size.height/2 ) {
bg1.center = CGPointMake(bg1.center.x, 690);
}
if (bg2.center.y <= - self.view.bounds.size.height/2 ) {
bg2.center = CGPointMake(bg2.center.x, 690);
bg1.center = CGPointMake(bg1.center.x, bg1.center.y - movement);
bg2.center = CGPointMake(bg2.center.x, bg2.center.y - movement);
But the faster i move the pictures the more problems occur: There are appearing gaps between the backgrounds and they are getting biggiger the faster i move them! movement is defined by the speed of swiping over the screen
Any idea to solve that?
You could try using the canvas element
Related
I recently started using Haxe, so pardon me if my question has an obvious answer or if my description of the problem is a little sloppy, but I'm going to try my best to explain it.
I'm working on a laptop that has a multitouch-supported track pad, and a normal optical mouse with only a vertical scroll wheel (no horizontal clicking available on there). I'm looking for a way to handle horizontal scroll input / events. OpenFL's mouse events support vertical scrolling well enough. Both the mouse scrolling and the two-finger track pad scrolling work fine for the vertical axis. It looks like the same event is generated when either of those input methods are used, which is understandable. But I can't seem to find an event that would be generated when a horizontal scroll is performed. The track pad allows for horizontal scrolling, since web browsers respond to the command, but I can't find any way to make my program respond to this input. Lime's "onMouseWheel" function doesn't respond to the input either. Do you guys have any suggestions for capturing this kind of input for an app targeted for Windows?
Thanks in advance
UPDATE: What I'm looking for here is not a question of how to scroll the screen horizontally, but how to recognize the horizontal scroll event coming from hardware, for example two fingers on the track pad or a sideways click of the middle mouse wheel. Lime's onMouseWheel has two params, deltaX and deltaY, but no events are triggered that give back a non-zero deltaX value. Vertical scrolling fires an event that returns deltaX = 0 and deltaY = +/- 1, but horizontal scrolling doesn't even trigger an event.
This can be done in several ways. The first is to add an event handler to mouse wheel for the object instance that you want to attach the event handler to, so MouseEvent.MOUSE_WHEEL and use the delta variable to determine the scroll direction. What you may also need to do is handle a key down event which enables horizontal scrolling instead of vertical.
Some example code:
mySprite.addEventHandler(MouseEvent.MOUSE_WHEEL, onScroll);
mySprite.addEventHandler(KeyboardEvent.KEY_DOWN, onKeyDown);
mySprite.addEventHandler(KeyboardEvent.KEY_UP, onKeyUp);
...
private var horizontal:Bool;
private function onScroll(e:MouseEvent):Void
{
if (e.delta > 0 && horizontal)
mySprite.scrollRect.x++;
else if (e.delta < 0 && horizontal)
mySprite.scrollRect.x--;
}
private function onKeyDown(e:KeyboardEvent):Void
{
if (e.keyCode == 18)
horizontal = true;
}
private function onKeyUp(e:KeyboardEvent):Void
{
if (e.keyCode == 18)
horizontal = false;
}
You will need to define the scrollRect in your constructor somewhere to specify the scrolling bounds of the sprite.
I'm trying to create functionality very similar to most websites these days.
The concept is 3 sections the size of the browser, the background images are supposed to be fixed positioned and revealed by the div scrolling up and down.
We need this to function as beautifully on mobile as it does on desktop, and it looks like Famous/angular is the solution.
Here is a pen.
http://codepen.io/LAzzam2/pen/XJrwbo
I'm using famous' Scroll.sync, firing javascript that positions the background image on every start / update / end.
scrollObject.sync.on("update", function (event) {
console.log('update');
test(event);
});
here is the function positioning the backgrounds.
function test(data){
var scroller = document.getElementsByClassName('famous-group');
styles = window.getComputedStyle(scroller[0], null);
tr = styles.getPropertyValue("-webkit-transform").replace('matrix(1, 0, 0, 1, 0,','').replace(')','');
var distanceTop = -(parseInt(tr));
var sections = document.getElementsByClassName('section');
sections[3].style.backgroundPosition="50% "+distanceTop+"px";
sections[4].style.backgroundPosition="50% "+(-(window.innerHeight)+distanceTop)+"px";
sections[5].style.backgroundPosition="50% "+(-(window.innerHeight*2)+distanceTop)+"px";
};
Any input / suggestions / advice would be wonderful, really just looking for a proof of concept with these 3 background images scrolling nicely.
That jittery-ness is unfortunate, I can't tell what would be causing the issue, except maybe the order in which events are fired?
**There are known issues, only works in -webkit browsers as of now
I think your idea to use Famous is good, but probably what I would do, would be taking a different approach to the problem.
You are solving this by touching the DOM, that is exactly what both Angular and Famous are meant to avoid.
If I had to face the same goal, I would probably use a Famous surface for the background instead of changing the property of the main one and synchronize its position with the scrolling view.
So, in your code, it would be something like this:
function test(data){
var scrollViewPosition = scrollObject.getAbsolutePosition();
var newBackgroundPosition = // Calculate the new background position
var newForegroundPosition = // Calculate the new foreground position
var backgroundSurface = backgroundSurface.position.set(newBackgroundPosition);
var foregroundSurface = foregroundSurface.position.set(newForegroundPosition);
};
I am trying to imitate what Apple has when showing the search result in the App Store. (reference: http://searchengineland.com/apple-app-search-shows-only-one-result-at-a-time-133818)
It shows like the detailed-application-info in a cards and it is paged. I am stuck at how to make the previous-and-next card shows when one active card in the middle and the scroll view's paging behaviour is still intact.
I have tried using the UICollectionView and set the clipSubviews to NO, hoping that it will show the previous page and the next page, but as soon as the cell goes off-screen, the cell gets hidden (removed from the view hierarchy) and not displayed. I think thats the flyweight pattern of the UICollectionView (the behavior of UICollectionView). Any ideas of what would be possible?
Cheers,
Rendy Pranata
The problem: UICollectionView as a subclass of UIScrollView essentially animates its bounds by a stride of bounds.size. Although this could mean that all you had to do is decrease the bounds while keeping the frame bigger, unfortunately UICollectionView will not render any cells outside its current bounds... destroying your preview effect.
The Solution:
Create a UICollectionView with paging set to NO and with the desired frame.
Create UICollectionViewCells that are smaller than the UICollectionView's frame/bounds. At this stage, a part of the next cell should show in the frame. This should be visible before implementing the other steps below.
Add a collectionView.contentInset.left and right (I assume your layout is horizontal) equal to the contentOffsetValue method (as shown below for simplicity) so as to align the first and last cells to the middle.
Create a UICollectionViewFlowLayout which overrides the method that gives the stopping point like so:
Like so:
-(CGFloat)contentOffsetValue
{
return self.collectionView.bounds.size.width * 0.5f - self.itemSize.width * 0.5f;
}
- (CGPoint)targetContentOffsetForProposedContentOffset:(CGPoint)proposedContentOffset withScrollingVelocity:(CGPoint)velocity
{
static float EscapeVelocity = 0.5f; // otherwise snap back to the middle
NSArray* layoutAttributesArray = [self layoutAttributesForElementsInRect:self.collectionView.bounds];
if(layoutAttributesArray.count == 0)
return proposedContentOffset;
CGFloat currentBoundsCenterX = self.collectionView.contentOffset.x + self.collectionView.bounds.size.width * 0.5f;
UICollectionViewLayoutAttributes* candidateNextLayoutAttributes = layoutAttributesArray.firstObject;
for (UICollectionViewLayoutAttributes* layoutAttributes in layoutAttributesArray)
{
if ((layoutAttributes.representedElementCategory != UICollectionElementCategoryCell) ||
(layoutAttributes == candidateNextLayoutAttributes)) // skip the first comparison
continue;
if(velocity.x > EscapeVelocity || velocity.x < -(EscapeVelocity))
{
if(velocity.x > EscapeVelocity && layoutAttributes.center.x > candidateNextLayoutAttributes.center.x)
{
candidateNextLayoutAttributes = layoutAttributes;
}
else if (velocity.x < -(EscapeVelocity) && layoutAttributes.center.x < candidateNextLayoutAttributes.center.x)
{
candidateNextLayoutAttributes = layoutAttributes;
}
}
else
{
if(fabsf(currentBoundsCenterX - layoutAttributes.center.x) < fabsf(currentBoundsCenterX - candidateNextLayoutAttributes.center.x))
{
candidateNextLayoutAttributes = layoutAttributes;
}
}
}
return CGPointMake(candidateNextLayoutAttributes.center.x - self.collectionView.bounds.size.width * 0.5f, proposedContentOffset.y);
}
I just put together a sample project which shows how you could do this. I created a container view which is 100 points wider than the 320 points for the screen. Then I put a UICollectionView into that container. This offsets everything by 50 points on both sides of the screen.
Then there is a content cell which simply has a background and a label so you can visually identify what is happening. On the left and right there are empty cells. In the viewDidLoad method the content inset is set to negative values on the left and right to make the empty cells now scroll into view. You can adjust the inset to your preference.
This mimics the behavior fairly closely. To get the label below, like in the example you can simply check the contentOffset value to determine which cell is in focus. To do that you'd use the UIScrollViewDelegate which is a part of UICollectionView.
https://github.com/brennanMKE/Interfaces/tree/master/ListView
You'll notice this sample project has 2 collection views. One is a normal horizontal flow layout while the other one which has larger cells is the one which mimics the example you mentioned.
I'm having a problem when I try to move the content of a UIScrollView with CoreMotion.
The thing is, I have a background with approximately 5000px, inside a container, which is inside my scrollView (is a landscape app); I already set the self.scrollView.bounces = FALSE;, my value for motion is attitude.pitch * 10.0; and when I move the content inside and it reaches the edge of the pointZero or the self.scrollView.contentSize.width it doesn't respect the bounds and keep moving in a white screen like it has no limit.
So, I set a verification (the code below), but when it reaches the pointZero it was supposed to stop but still give me a little white border. I set a NSLog and I saw that the contentOffset was still going till x =-14, like the bounce was active. The pitch value is controlling that because when the pitch value is zero the content stays at pointZero, when I raise the value of the pitch ir keep going till -14.
I think that is something wrong with my verification, if anyone can help I will be really grateful!!
self.accel = attitude.pitch *10.0;
//"pointZERO"----------------
if (self.gameArea.contentOffset.x <= self.gameArea.frame.origin.x) {
NSLog(#"%2.f",self.gameArea.contentOffset.x);
self.gameArea.contentOffset = CGPointZero;
} else {
self.gameArea.contentOffset = CGPointMake(self.gameArea.contentOffset.x + self.accel,0.0);
}
//"END OF SCREEN"------------------------
if (self.gameArea.contentOffset.x + self.gameArea.frame.size.width >= self.gameArea.contentSize.width) {
NSLog(#"%2.f",self.gameArea.contentOffset.x);
self.gameArea.contentOffset = CGPointMake(self.gameArea.contentSize.width - self.gameArea.frame.size.width ,0.0);
} else {
self.gameArea.contentOffset = CGPointMake(self.gameArea.contentOffset.x + self.accel,0.0);
}
I have a weird problem with PowerPoint 2010:
I use the following code to remove all animations from a slide. This is done during slideshow:
for (int i = slide.TimeLine.InteractiveSequences.Count; i >= 1; i--)
{
Sequence sequence = slide.TimeLine.InteractiveSequences[i];
for (int x = sequence.Count; x >= 1; x--)
{
sequence[x].Delete();
}
}
for (int i = slide.TimeLine.MainSequence.Count; i >= 1; i--)
{
slide.TimeLine.MainSequence[i].Delete();
}
}
In one slide, which has a Picture and a TextBox and both use the MainSequence animation, after the animations are removed, the Slide appears in the slideshow with only the text but not the picture.
In another slide, after animations are removed, the textbox and the picture are both shown, but are drawn only half down - it really looks as if somebody took a rubber and wiped the bottom parts out! Very weird.
Here's an example screenshot. Notice the image on the right of the slide, which has its bottom half wiped off:
Redrawing the slides by using View.GotoSlide does not fix this. Adding an extra shape to the slides before/after removing the animations, does not help either.
When I create PNG thumbnails of these weird slides, the thumbnails look fine and contain all the shapes.
Any ideas?
This type of redraw bug has come up before. After changing the visibility of shapes (or in this case, the animations) try moving them off the slide then back on again. That seems to help in some case.