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How to prevent touches prematurely stopping smoothScroll in RecyclerView?

I am using an Adapter to fill a RecyclerView with numerous CardView layouts (horizontally). Each CardView has a Button at the bottom of the layout, which when pressed prompts the call:
recyclerView.smoothScrollBy(x, y);
This scrolls horizontally to the next card as expected, unless the user touches the screen as it is scrolling. I have attempted disabling the TouchEvent for the RecyclerView and the CardView to no avail.
I obviously cannot rely on a user to not touch the screen during this scrolling animation, so I was wondering if anyone had any ideas as to why the scrolling is halted prematurely and how I can stop it.
Thanks.

problem is onInterceptTouchEvent
if you add listener to recyclerView this way:
addOnItemTouchListener(object : RecyclerView.SimpleOnItemTouchListener() {
override fun onInterceptTouchEvent(rv: RecyclerView, e: MotionEvent): Boolean {
return true
}
})
if it is return true you can't scroll recyclerView manually (programmatically you can)
if it is return true scrolling is stopped/interrupted
this option worked for me (add this to recyclerView with previous code snippet (to prevent manual scrolling) to prevent scrolling interrupt on touch):
override fun onInterceptTouchEvent(e: MotionEvent): Boolean {
if (layoutManager?.isSmoothScrolling == true || scrollState == SCROLL_STATE_SETTLING) {
return true
}
return super.onInterceptTouchEvent(e)
}
override fun onTouchEvent(e: MotionEvent): Boolean {
if (layoutManager?.isSmoothScrolling == true || scrollState == SCROLL_STATE_SETTLING) {
return true
}
return super.onTouchEvent(e)
}

Disable user interactions before the scroll and reenable them a little after. I would use window flags:
getWindow().setFlags(WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE,WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE);
recyclerView.smoothScrollBy(x, y);
new Handler().postDelayed(new Runnable() {
public void run(){
getWindow().clearFlags(WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE);
}
}, 500);

SearchView cant restore search function after closing

I have a structure where a search view resides at the top and a frame layout does below. SearchAFragment is the initial fragment of frame layout.
I am managing frame layout like;
search_box.setOnSearchClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
changeFragment(new SearchBFragment(), id);
}
});
search_box.setOnCloseListener(new SearchView.OnCloseListener() {
#Override
public boolean onClose() {
changeFragment(new SearchAFragment(), id);
//search_box.clearFocus();
return false;
}
});
I am clicking search view and then searching things and everything is all right. After searching, I click close button of search view to switch to SearchAFragment and then the problem occurs. It switches SearchAFragment but when I try to open search view and search things again, SearchBFragment never comes to front. How can I handle this problem?

screenshots don't change when layout changes

I'm using ViewPager as my main navigation in app. I'm using ActionBar, as well. What I want to achieve is that when user clicks search button in ActionBar I want to have blurred background. So my approach is to take a screenshot, blur it, set as ImageView and display as an overlay over the whole view. And it works. But problem is that actually when I first open search it displays proper screenshot. Then I turn overlay off, change page in ViewPager, click search again and ... I can see the previous screenshot- not new one with new page on it. Here are my snippets of code:
show and hide overlay on search click (I'm passing R.id.container view which is parent id of my content view, menuOverlay is my ImageView referenced from layout)
Here's my method that takes screenshot and makes it blurry
// Ad. 1
item.setOnActionExpandListener(new MenuItem.OnActionExpandListener() {
#Override
public boolean onMenuItemActionExpand(MenuItem menuItem) {
if(menuItem.getItemId() == R.id.action_search) {
menuOverlay.setImageBitmap(Utils.takeSnapshot(findViewById(R.id.container)));
menuOverlay.setVisibility(View.VISIBLE);
}
return true;
}
#Override
public boolean onMenuItemActionCollapse(MenuItem menuItem) {
if(menuItem.getItemId() == R.id.action_search) {
menuOverlay.setVisibility(View.GONE);
}
return true;
}
});
// Ad. 2
public static Bitmap takeSnapshot(View v) {
v.setDrawingCacheEnabled(true);
v.buildDrawingCache();
Bitmap bm = v.getDrawingCache();
Bitmap scaled = Bitmap.createScaledBitmap(bm, bm.getWidth()/5, bm.getHeight()/5, false);
return Utils.fastblur(scaled, 5);
}
I;m using fast blur algorithm found somewhere here on StackOverflow which is quite fast.
Where's the problem? Why it happens?

ok, I found the answer. if you want to always have "fresh" screenshot you need to destroy cache after all operations:
v.setDrawingCacheEnabled(false);

Action Bar Home Button not functional with nested PreferenceScreen

I found a workaround to actually enable the ActionBar home button on the nested PreferenceScreen... however it doesn't call OnOptionsItemSelected in my PreferenceActivity. Anyone know a way to actually use the home button on a nested PreferenceScreen?
Modification of post 35 here:
http://code.google.com/p/android/issues/detail?id=4611
#Override
public boolean onPreferenceTreeClick(PreferenceScreen preferenceScreen, Preference preference)
{
super.onPreferenceTreeClick(preferenceScreen, preference);
if (preference!=null)
if (preference instanceof PreferenceScreen)
if (((PreferenceScreen)preference).getDialog()!=null)
((PreferenceScreen)preference).getDialog().getActionBar().setHomeButtonEnabled(true);
return false;
}

I had this problem recently and this is how I solved it. Firstly to access the PreferenceScreen I use the exact same method you mentioned above.
#Override
public boolean onPreferenceTreeClick(PreferenceScreen preferenceScreen, Preference preference) {
super.onPreferenceTreeClick(preferenceScreen, preference);
// If the user has clicked on a preference screen, set up the action bar
if (preference instanceof PreferenceScreen) {
initializeActionBar((PreferenceScreen) preference);
}
return false;
}
From here I looked into what a PreferenceScreen is, and I was saddened to find out it is just wrapper of a Dialog. Moving forward, I then set the actionbar display options and attempt find the home button area. This unfortunately wasn't too easy to get, but with the help of the hierarchy viewer I managed to gain access by finding the home icon and then its parent views. Once we have access to the containing LinearLayout, we can attach an onClickListener where we dismiss the PreferenceScreen's dialog, which calls PreferenceScreen's onDismissListener and returns us to the previous screen.
/** Sets up the action bar for an {#link PreferenceScreen} */
public static void initializeActionBar(PreferenceScreen preferenceScreen) {
final Dialog dialog = preferenceScreen.getDialog();
if (dialog != null) {
// Inialize the action bar
dialog.getActionBar().setDisplayHomeAsUpEnabled(true);
// Apply custom home button area click listener to close the PreferenceScreen because PreferenceScreens are dialogs which swallow
// events instead of passing to the activity
// Related Issue: https://code.google.com/p/android/issues/detail?id=4611
View homeBtn = dialog.findViewById(android.R.id.home);
if (homeBtn != null) {
OnClickListener dismissDialogClickListener = new OnClickListener() {
#Override
public void onClick(View v) {
dialog.dismiss();
}
};
// Prepare yourselves for some hacky programming
ViewParent homeBtnContainer = homeBtn.getParent();
// The home button is an ImageView inside a FrameLayout
if (homeBtnContainer instanceof FrameLayout) {
ViewGroup containerParent = (ViewGroup) homeBtnContainer.getParent();
if (containerParent instanceof LinearLayout) {
// This view also contains the title text, set the whole view as clickable
((LinearLayout) containerParent).setOnClickListener(dismissDialogClickListener);
} else {
// Just set it on the home button
((FrameLayout) homeBtnContainer).setOnClickListener(dismissDialogClickListener);
}
} else {
// The 'If all else fails' default case
homeBtn.setOnClickListener(dismissDialogClickListener);
}
}
}
}

Adding a Button on a View

I am going nuts over this.
I did not find any working solution (tried a few from stackoverflow)
Scenario (this is an actual screenshot what is already done):
I have a Activity that has a View as his Attribute.
This view adds another view via View.addView(myView).
I now want to add a Button to myView (to be specific: after MotionEvent.ACTION_UP the button should appear in the right lower corner (this will start the robot to drive the track))
Here is a shortcut of my code:
public class ModeRouting extends View {
public ModeRouting(Context context) {
super(context);
Button asuroStartButton = new Button(context) //does not work
}
#Override
public boolean onTouchEvent(MotionEvent event) {
int actionevent = event.getAction();
if (actionevent == MotionEvent.ACTION_UP
|| actionevent == MotionEvent.ACTION_CANCEL) {
asuroStartButton.visible=true;
view.add(asuroStartButton);
}
return true;
}
}
and my Activity:
//in constructor
contentView = (FrameLayout) findViewById(R.id.content);
onClickListenerFacade(routingMode, route);
//this removes all views from stack and places the new one on the view
private void onClickListenerFacade(View v, final View target) {
v.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View arg0) {
contentView.removeAllViews();
contentView.setBackgroundColor(0xff000000);
contentView.addView(target);
modeSelectorAnimation();
}
});
}
I tried to create a button in my mainactivity.xml and instantiate in my mainactivity.
I am missing some point in here but i am not sure which.
Since my view is purely dynamic (no layout.xml) i dont think i should use a layout.xml (maybe thats my mind-blockage) but instead set the button attributes dynamically too.
Any hint is appreciated!

You want to extend ViewGroup rather than just a View (LinearLayout, RelativeLayout, FrameLayout, etc) - they handle child views for you.

I think maybe you need to refresh the whole view/activity. Try to do this in the onResume methode, maybe this helps. But as you don't use a layout.xml, I'm not sure if this helps you much..
#Override
protected void onResume(){
super.onResume();
setContentView(R.layout.activity_main);
}