I want to programatically scroll a View. So far, I have found two possibilities :
scrollTo(x,y) : the top left hand corner of the View corresponds to the point (x,y) of what must be drawn in the View. The problem is that, after the call, it is impossible to manually scroll the View to have it displays what is above y or what is at the left of x.
setScrollY(y) : seems to be the function I'm looking for. But it is only available for API above level 14. And my application is supposed to work with API level 8.
Is there another function which could do what I want to do?
Thanks in advance for the time you will spend trying to help me.
Is your View in a ScrollView? If not, you will need to handle events yourself to manually scroll the View after you use code to set the scroll location. It sounds like you want both manual and programmatic control, so you'll need to use a scrolling container or handle touch events yourself.
Related
I am attempting move a Button around in an Android app I'm making (Java). Under certain circumstances in onResume(), I get margin information about the button, then attempt to place the button at the left edge of the screen with that margin as a slight gap so it looks nice. See below.
ViewGroup.MarginLayoutParams lp = (ViewGroup.MarginLayoutParams) button.getLayoutParams(); button.setX(lp.leftMargin);
However, apparently the information in my xml layout file gets read AFTER I programmatically set the button position. So, my button is getting placed exactly in the middle of the screen (as stated in xml file) PLUS 8 dp to the right. I need a way to reorder these positioning commands -- Anyone know how to queue up a dynamic view placement in onResume so it delays just enough to occur immediately after the button is done being placed by my layout file?
Found it!! I guess it was a duplicate question, I couldn't find it searching before:
https://stackoverflow.com/a/24035591/14116101
Attached screenshot of netflix app with left side menu I am able to develop a side menu with customized icon and header in it. I want, when the focus comes on header fragment it should expand on top of row fragment, that is not collapsing the row fragment, the same as Netflix and hotstar are doing. How can I achieve it?
unfortunately, the HeaderSupportFragment used in the BrowseSupportFragment is not configurable enough to achieve this kind of design. Leanback is great to build quickly and easily media browser app but when it comes to "complex" design, it's easier to use custom component.
The major difference also here, is that the left menu of the BrowseSupportFragment show each rows header name displayed in the screen (that's why it's called HeaderSupportFragment). Here you want to show different entries like search, home, settings, etc.
To make this kind of view, I would suggest creating your own custom view and use a basic Fragment. I followed this tutorial which can be useful to handle menu open/close animation (I mixed it with a ConstraintLayout to simplify the animation and I made the menu overlap the rest of the screen instead of moving everything.)
See the tutorial: https://medium.com/building-for-android-tv/building-for-android-tv-episode-3-381e041dfec7
I have a RecyclerView with the implementation of ItemTouchHelper. I am dragging and sorting the items in RecyclerView using ItemTouchHelper.
Also I am performing different actions on different direction of swipe. If user goes from left to right (Swipe) I just Deactivate status of item. If he perform right to left swipe I activate the relevant item.
What I want:
But now here comes the change, What I want is that I need to show some icons after I perform right or left swipe. And By clicking on those icons/buttons I want to perform action then.
Problem:
Problem is as I told you I have implementation of ItemTouchHelper, then how I am doing to perform what I wanted (as described above)
How to solve this? I have seen many libraries but they have limitations, also as the app has very much things going and there are some more implementations on RecyclerView used in our app, so I really do not want to risk the rest of implementations for the sake of this..
UPDATE 1:
To clear my question more I am going to add on more. Right now My implementation is something like this. But this is not what I want. I want to show swipe menu for any type of swipe I mean either it is left or right I want to show some icons on left and right side of item
You can take iOS swipe menu as an example (see here). I want exactly same behavior in android.
You're asking the impossible: suggest a library that doesn't exist (as you have already found out).
You're asking people to also find a solution for a problem you only briefly describe. You're not providing any code whatsoever, nor any specific issue you're facing when trying to come up with a solution; you're essentially expecting magic to happen.
How can you make this better?
Provide something like: "I'm attempting to implement a swipe solution for a recycler view's row; when I try to do YYYY is happening instead. Hhere's my piece of code where I do , calculated like this , am I missing something?"
Anyway...
You claim to be using an ItemTouchHelper already, so, if you look at how a very basic one works, you'll notice that the helper will ultimately draw on the canvas directly via:
#Override
public void onChildDraw(
final Canvas canvas,
final RecyclerView recyclerView,
final RecyclerView.ViewHolder viewHolder,
final float deltaX,
final float deltaY,
final int actionState,
final boolean isCurrentlyActive) {
This is derived from the platform ItemTouchHelper.SimpleCallback. So...
If you want to implement your solutions, you'll need to implement it there to do things like stop dragging, draw the content (icons), etc.
It's not a trivial solution and getting the whole thing right is difficult; more so if you introduce "some more implementations on RecyclerView".
I hope this answer points you in the right direction, and that your next related question is more about what you've tried (and failed) to do, than a "please do this for me" scenario. (If your intentions weren't those, please apologize, but you spent 5 minutes typing this question and it would take hours/days to implement this, so set your expectations this time).
Finally, when I wrote this, I realized most people wanted iOS swipe behavior; unfortunately, said behavior is not pre-implemented (like on iOS) on Android and you have to deal with it yourself; it's not impossible nor the most difficult task on earth to do on Android, but will give you a few headaches if you're hacking RecyclerView too much.
UPDATE
You've realized now, that ItemTouchHelper has a problem. It draws on the Canvas directly, so it has no knowledge of a Layout, View, Margin, etc. These are all things that live outside the realm of the touch helper. The helper is given a canvas, and drawing capabilities and that's it.
Where does this canvas size come from?
Well, it's calculated during the layout/measure pass(es) for the RecyclerView and its views.
How do I then stop dragging "at exactly the center of the screen" then?
Pass the values to your Helper; remember that the responsibility of calculating where the middle of the screen is, is not in the TouchHelper's contract; but your Activity/Fragment does know this. Provide the information the Touch Helper needs to perform the things you want it to perform.
Revert "back" to the original position, means knowledge of what the initial state was, etc. All this information is known by the RecyclerView and beyond, not the TouchHelper.
So you'd need to measure your layouts, save some values, pass them to the touchhelper so it can operate, etc.
As you can see, the full picture starts to become more and more complicated. My advice to you is:
Try to push this feature OUT as "the platform doesn't do it it will take time, it's not worth" (the worthiness and discoverability of swipe actions is dubious at best, but it's an ubiquitous action nowadays so you may have to do it regardless).
If you really have to do this, abstract things as much as you can, create all the classes/interfaces you think you can need, even if you end up with a "MiddleScreenCalculatorDelegate" kind of thing. It will be easier to fix later, but at least have each component do a very small subset of things.
Lastly, your item touch helper will have to calculate how much offset (delta) has the view been swiped already and stop when it reaches a known threshold.
Good luck :)
p.s.: I suggest you post a different question with specific issue(s) to get better help, this answer is very unhelpful as it is. :)
I am trying to show a fragment with right to left animation, as though it is coming from the right side of the screen but my code does exactly the opposite.
flBackground.animate().setDuration(250).x(0).translationX(0).alpha(1).start();
flBackground here is the id of the root view in my fragment.
I played with 'translationX' method. I gave the screen width in pixels, but my fragment got off screen. Is there a way in ViewPropertyAnimation that I can set initial positioning of a view to animate from?
I only want to use ViewPropertyAnimation, not other Animation objects. Other ones are quite big and I want simple code for my project.
You can use FragmentTransaction.setCustomAnimations(). It's the best way.
Example:
getFragmentManager().beginTransaction()
.setCustomAnimations(R.animator.slide_right, R.animator.slide_left)
.add(R.id.list_fragment_container, YourFragment.instance())
.commit()
More: https://developer.android.com/reference/android/app/FragmentTransaction#setCustomAnimations(int,%20int,%20int,%20int)
So I have a question about best practice for dynamically creating and sizing buttons within a ViewPager, based on a changing external state.
Essentially, I have a scrolling view and I want my ViewPager to contain a number of buttons of a specific size and count depending on what part of the scrolling view is currently visible.
My question is about deciding the best implementation of this feature, I see two options: would it be simpler to
Constantly create and scale new buttons whenever the scrolling view moves
Make the viewpager itself contain a scrollview and fill it with all of the pre-scaled buttons on app startup. Then, whenever the user scrolls the main scrollview the viewpager's scrollview (which contains the buttons) will scale programatically
Any ideas on which would be the simpler and more robust system?
Not much of an answer but I will leave a comment for ya! Basically you can do it either way, both aren't to difficult to accomplish, however I would probably go the dynamic route because it will always scale correctly. Doing a set amount will only work until devices become larger, or if you are targeting tablets or tvs then it will start to become extremely messy in the xml file for the layout. Dynamically adding also gives you far more control and saves time later on, you can simply change a number and have 100 more then going through and manually adding even 10. Hope this helps!