My tvOS app generates a game board using SKNodes that looks like the following:
Each shape, separated by lines, is an SKNode that is focusable (e.g. each colored wedge is composed of 5 SKNodes that gradually diminish in size closer to the center).
My problem is that the focus engine doesn't focus the next focus item (SKNode) that would feel like the logical, most natural next node to focus. This issue is because the focus engine logic is rectangular while my SKNodes are curved. As you can see below, there are inherent problems when trying to figure out the next focusable item when swiping down from the outermost yellow SKNode:
In the example above, the focus engine deducts that the currently focused area is the area within the red-shaded rectangle based on the node's edges. Due to this logic, the focused rectangle overlaps areas that are not part of the currently focused node, including the entire width of the second yellow SKNode. Therefore when swiping downward, the focus engine skips focus to the third (middle) yellow SKNode.
How would one go about solving this focus issue so that focus is more natural both vertically and horizontally for my circular game board of SKNodes without seeming so sporadic? Is this possible? Perhaps with UIFocusGuides?
You have to handle the focus manually. Use the methods listed below to check for the next focused view from the context.
func shouldUpdateFocus(in context: UIFocusUpdateContext) -> Bool
In this method, you will get the focus heading direction (UIFocusHeading). Intercept the required direction and save your required next focused view in some property. Manually update the focus by calling below methods
setNeedsFocusUpdate()
updateFocusIfNeeded()
This will trigger the below
preferredFocusEnvironments: [UIFocusEnvironment] { get }
In this check for saved instance, and return the same. This will help you handle the focus manually as per your requirements.
Related
I have a badge animation that has a child of text and then a button that decreases the level that should always appear behind the score badge.
I have tried a lot of things(like sorting layer component but then the badge renders over all UI elements even its child text) but fundamentally I changed the Decrease level and Text to just be Default for the layer option and set the Z position and scale to 0. I have then changed the Score Badge and its child to be layer UI and negative coordinates so they appear in front of the camera but the issue still persists.
Here is the editor hierarchy
The issue I am having is the rendering looks like this:
If you use Layers try dragging it in sorting layers the one in the bottom of the stack will render in front.
The thumbstick on lower left controls player movement in roblox for touch enabled devices. I would like to place some gui elements in that same corner (under the thumbstick) which are just for display like frames or text labels (not buttons or input elements). Its a good place in my opinion to put things that the player might want to glance at occasionally but not interact with directly.
When I place these elements it blocks the normal thumbstick behavior. The thumbstick is drawn on top of the gui elements like I want but I cant click the part of the thumbstick that is on top of other gui elements. When I inspect an active game I can see the thumbstick is at z index 1 and I put my gui elements at zindex -1 so really not sure why its blocking things.
NM found the elements were marked selectable and active. I disabled those thumbstick works now.
I am wondering what is the equivalent of the web api DocumentOrShadowRoot.elementFromPoint() in flutter.
Specifically, I am wondering how I could figure out what is the leaf element/widget instance in a widget hierarchy, given an Offset.
For example, consider the following structure:
For the First Offset marked with a dark circle, I would expect to get some sort of data that can help me figure out the offset is over Container.
For the Second Offset marked with a dark circle, I would expect the stack.
For the last one, it would be the positioned element.
A bit of context
I'm exploring the implementation of a visual editor similar to FIGMA in Flutter. I have experience in implementing such a rendering system with web technologies.
I want to render a selection indicator or outline when a tap/click happens on each element. These elements are nested. Adding multiple nested event handlers triggers all of them. For example, mouse enter and mouse leave when moving the mouse over the Stack or Positioned element would trigger all the parent event handlers as well.
Any help or guidance would be appreciated.
Simple answer to your exact question: No direct equivalent. Possible to implement but not advisable.
You could theoretically implement your own version of elementFromPoint() by looking at how GestureBinding works in Flutter. That would be a deep dive for sure, and you might learn from it, but there is a simpler solution. Even if you implement your own method, then you would still need to resolve conflicts when more than 1 element is found - and this is something Flutter solves out of the box with the gesture arena.
I see that you expect the top-most or deepest child to be reported, something that you can obtain by using the GestureDetector widget. What you're looking for is making your gesture detectors opaque. A GestureDetector has a property called behaviour of type HitTestBehaviour. The default for it is deferToChild. Here are the possible values:
/// How to behave during hit tests.
enum HitTestBehavior {
/// Targets that defer to their children receive events within their bounds
/// only if one of their children is hit by the hit test.
deferToChild,
/// Opaque targets can be hit by hit tests, causing them to both receive
/// events within their bounds and prevent targets visually behind them from
/// also receiving events.
opaque,
/// Translucent targets both receive events within their bounds and permit
/// targets visually behind them to also receive events.
translucent,
}
What follows is slightly related, so consider it a deep dive in your use-case
Since you're going down this path: I also built a WYSIWYG design system, with selection indicators, handles for rotating, resizing, etc. and have one advice: Completely separate your design rendering from your gesture detectors and selection indicators.
I initially put the gesture detectors "around" the design elements - in your example, the gesture detectors would sit in between yellow / blue / green / red. The reason this is a bad idea is that it complicates a few things. In some cases I needed to create touch areas larger than the design elements themselves, in which case I needed to add padding and reposition the GestureDetector parents. In other cases the design elements would become fixed or locked and would not have a GestureDetector parent and Flutter would completely rebuild the contents of the layer since tree comparing got confused. It gets messy fast. So, stack these layers:
Design on bottom, no interactivity.
Selection indicators, resize / rotate handles. Still no interactivity
Gesture detectors for all design elements. If you're lucky, you know the exact size, position, rotation for the design elements you can simply use Positioned. If you have groups of design elements, then your gesture detectors also get grouped and transformed together. If you also have self-sizing design elements (like images), it gets a bit more complicated, but I got around my issues by adding the design element as an invisible child. The way I would do this now is by loading meta-data about the images and knowing them at build time (as opposed to waiting for images to load and produce layout changes).
Selection indicators + resize / rotate handles gesture detectors. They are top-most and also opaque, so they catch everything that hits them.
This setup then allows you to experiment more in the gesture department, it allows you to use colored boxes to debug and in general will make your life easier.
TLDR: Use opaque gesture detectors.
I am building a chess board component, in which we should move the pieces by a simple Drag And Drop. In order to ease the drag and drop, I also try to draw a feedback which is a "cross of cells" centered around the pointer.
So, I am trying this way :
I draw a container that starts at the pointer location
Inside that container, I draw the entire cross, also drawing the dragged piece at the center of this container
So, I need a way to shift that feedback half to the left and to the top. That is, I need the feedback to be positionned to left and to the top of the pointer location.
Is that possible ?
I've tried playing with feedback and dragAnchor properties of Draggable, but I did not achieve.
In gamesalad framework I am creating a game in which I have an actor which only moves on x-axis on touch is pressed. But when I move it to x-axis the actor goes away out of the range of the screen. Let me clarify that I am new to gamesalad framework.
plz help to solve the problem.
I'm reading this in two different ways:
1 - when you press your touch controls the actor disappears from the screen
2 - when you press the touch control the actor moves along the x-axis and out of the screen
For the sake of argument I'm going to assume that we're talking about number two.
What you'll need to do is restrict the actors movement to the boundaries of the current screen. You can do this is two ways with Gamesalad
1 - create an invisible barrier for your actor to collide against
2 - use a behaviour to prevent your actor from going beyond the screen boundary
I'll explain both:
1, Invisible barriers
What you'll do is create a new actor, and set it to collide with the actor that your controlling. You'll create a few instances of this actor to create a walled area for your actor. Although this works, it's a little cludgy and using additional actors in a scene take a little performance away from your application.
2, using a behaviour
In my opinion the better way is to use the given behaviours in Gamesalad itself.
To stop the player actor from moving off screen you can use a combination of Rules and the Constrain Attribute behaviour to achieve this.
The first thing to know is your screen size; for an iPad I believe it's 1074 along the x-axis.
So to stop the actor moving off either side of the screen you'll need to do the following:
Open up the player actor
the click on the "Create Rule" button on the top right.
A new rule window will appear, but default the first dropdown will say "Actor receives event" change this to "Attribute".
Next select the attribute to use the rule against, since we're interested in the x-axis we'll want to query that player attribute which will be:
(also known as self) > Position > X
Select the greater than symbol (">") and then enter the maximum width of the screen minus whatever border value you want, so I'll use 1014 (1024 - 10).
Find and drag the Constrain Attribute behaviour into your rule a set the actors X position to 1014.
This will stop the actor from going beyond one side of the screen, now copy the rule and amend the settings to that if the actor goes less than, say 10, it will constrain the actors X position to 10.
I'd post an image, but alas my Karma isn't large enough right now! Hence the large explanation!
Hope this is what you're looking for!
It is way easier than that.
In top of the Gamesalad Creator there is a play button, which you probably know, displays your progress. To the left of this button there is a button that looks like a little video camera, it changes the camera settings. So what you first have to do is click the camera button, then the rectangular camera screen will show itself as marked. In the center of each of the sides of the highlighted rectangular which is the camera screen, sits 1 little grey rectangular. Each of these needs to be pulled to the center of the camera view so that you get a little grey "cross" in the center and from the center to the boarder there will now be this highlighted color.
Second and last step is easy, just go under your character and in (type or drag in a behavior block) you type control camera... or drag the control camera block, which as by the type box is statet possible.
Since Gamesalad only can have one camera at a time, and you character is the only one with the control camera option applied it will follow him and only him. Wherever your character starts on the screen, the camera will follow it when it passes through the center of the screen. You may know this from Super Mario Bros. Where you start of a little to the left and walk right and the second Mario enters the center of the screen, the camera follows him from then on.
Hope this helps... :