I trying use Room to inflate the Database in an RecyclerView, but all this using Fragments. I have the screen where the user enters the data and the screen where the RecyclerView is inflated, but I don't know how to make the Room data inflate in the RecyclerView and I still can't understand the viewModel.
For Getting data from Room this might get helpful
and for view modal this helped me.
after getting data from Room you can simply notify the adapter.
example :
var myList = ArrayList<YourModel>()
roomDataList.forEach { item ->
//You can parse or convert your data according to your use
myList.add(item)
}
adapter.updateList(myList)
I work on an app where I have a recyclerview and a fab on the first fragment (listFragment) you see when you open the app. you click the fab, camera opens, you make a picture -> click ok and get to another fragment, there you fill out some stuff and then press save. you get back to the recyclerview fragment and now you can see the saved entry (room database). when you click the listItem you created before you get to an update fragment where you can either update stuff or delete it. now before it all worked fine.
But now with help of a yt video I tried to also insert a bitmap into the database. That works (#TypeConverter) and now I also have the right bitmap displayed in the listItem and the updateFragment.
The problem:
When I click on a listItem and in the updateFragment I click the update button or delete icon that works fine and I get back to the listFragment. But when I then click on the fab in order to create a new entry the camera opens and then the app crashes (and the camera stays open).
Even when the delete and update code is commented out and the only thing that happens when you click these buttons is the navigation between fragments it still crashes but if I remove all the bitmap database code it is fine again. I can delete and/or update multiple entries no problem but when I click the fab and camera starts the app crashes. I also use safeargs for transportation of data to updateFragment when I click the listItem. The app also crashes when I delete/update something and then leave the app by pressing the homebutton on the phone. I navigate out of the app and then get the "app crashed" message.
LOGCAT:
java.lang.RuntimeException: android.os.TransactionTooLargeException:
data parcel size 4675628 bytes
I also found out that if I delete/update multiple entries in a row and then click the fab and the camera opens the amount of bytes multiply. For the following number to be reached I deleted 5 listItems in a row:
TransactionTooLargeException: data parcel size 23309336 bytes
I just wonder what type of data that is and why does it stack up for every navigation between my updateFragment and listFragment(as even when the code for deleting and updating is removed that still happens)? And why does it then become a problem when I start the camera or close the app per homebutton? Maybe contrary to my original believe the bitmap being display in the listItems and the updateFragment are somehow the problem. I display high quality bitmaps by using a fileprovider because in the addFragment and the updateFragment the imageViews are rather big and i use the same bitmap for the small imageViews on the listItems.
If anyone has any idea why that might happen I would be super gratefull!
Author here:
Found an answer to my problem even though I still don't completely get it.
Instead of using a #TypeConverter to turn a bitmap into a byteArray on storing it in the database and on retrieving turning it form byteArray back to bitmap i now store a uri as a string. I found that code which turns a bitmap into a uri and stores the bitmap on the device and it works like a charm:
private fun saveImageToInternalStorage(bitmap: Bitmap): Uri {
val wrapper = ContextWrapper(applicationContext)
var file = wrapper.getDir(IMAGE_DIRECTORY, Context.MODE_PRIVATE)
file = File(file, "${UUID.randomUUID()}.jpg")
try{
val stream : OutputStream = FileOutputStream(file)
bitmap.compress(Bitmap.CompressFormat.JPEG, 100, stream)
stream.flush()
stream.close()
}catch (e: IOException){
e.printStackTrace()
}
return Uri.parse(file.absolutePath)
}
companion object{
private const val IMAGE_DIRECTORY = "...Images"
}
I am using The new Navigation Architecture Component in android and I am stuck in clearing the navigation stack after moving to a new fragment.
Example:
I am in the loginFragment and I want this fragment to be cleared from the stack when I navigate to the home fragment so that the user will not be returned back to the loginFragment when he presses the back button.
I am using a simple NavHostFragment.findNavController(Fragment).navigate(R.id.homeFragment) to navigate.
Current Code :
mAuth.signInWithCredential(credential)
.addOnCompleteListener(getActivity(), new OnCompleteListener<AuthResult>() {
#Override
public void onComplete(#NonNull Task<AuthResult> task) {
if (task.isSuccessful()) {
NavHostFragment.findNavController(LoginFragment.this).navigate(R.id.homeFragment);
} else {
Log.w(TAG, "signInWithCredential:failure", task.getException());
}
}
});
I tried using the NavOptions in the navigate(), but the back button is still sending me back to the loginFragment
NavOptions.Builder navBuilder = new NavOptions.Builder();
NavOptions navOptions = navBuilder.setPopUpTo(R.id.homeFragment, false).build();
NavHostFragment.findNavController(LoginFragment.this).navigate(R.id.homeFragment, null, navOptions);
First, add attributes app:popUpTo='your_nav_graph_id' and app:popUpToInclusive="true" to the action tag.
<fragment
android:id="#+id/signInFragment"
android:name="com.glee.incog2.android.fragment.SignInFragment"
android:label="fragment_sign_in"
tools:layout="#layout/fragment_sign_in" >
<action
android:id="#+id/action_signInFragment_to_usersFragment"
app:destination="#id/usersFragment"
app:launchSingleTop="true"
app:popUpTo="#+id/main_nav_graph"
app:popUpToInclusive="true" />
</fragment>
Second, navigate to the destination, using above action as parameter.
findNavController(fragment).navigate(
SignInFragmentDirections.actionSignInFragmentToUserNameFragment())
See the docs for more information.
NOTE: If you navigate using method navigate(#IdRes int resId), you won't get the desired result. Hence, I used method navigate(#NonNull NavDirections directions).
I think your question specifically pertains on how to use the Pop Behavior / Pop To / app:popUpTo (in xml)
In documentation,
Pop up to a given destination before navigating. This pops all non-matching destinations from the back stack until this destination is found.
Example (Simple Job hunting app)
my start_screen_nav graph is like this:
startScreenFragment (start) -> loginFragment -> EmployerMainFragment
-> loginFragment -> JobSeekerMainFragment
if I want to navigate to EmployerMainFragment and pop all including startScreenFragment then the code will be:
<action
android:id="#+id/action_loginFragment_to_employerMainFragment"
app:destination="#id/employerMainFragment"
app:popUpTo="#+id/startScreenFragment"
app:popUpToInclusive="true" />
if I want to navigate to EmployerMainFragment and pop all excluding startScreenFragment then the code will be:
<action
android:id="#+id/action_loginFragment_to_employerMainFragment"
app:destination="#id/employerMainFragment"
app:popUpTo="#+id/startScreenFragment"/>
if I want to navigate to EmployerMainFragment and pop loginFragment but not startScreenFragment then the code will be:
<action
android:id="#+id/action_loginFragment_to_employerMainFragment"
app:destination="#id/employerMainFragment"
app:popUpTo="#+id/loginFragment"
app:popUpToInclusive="true"/>
OR
<action
android:id="#+id/action_loginFragment_to_employerMainFragment"
app:destination="#id/employerMainFragment"
app:popUpTo="#+id/startScreenFragment"/>
In my case i needed to remove everything in the back Stack before i open a new fragment so i used this code
navController.popBackStack(R.id.fragment_apps, true);
navController.navigate(R.id.fragment_company);
the first line removes the back Stack till it reaches the fragment specified in my case it's the home fragment so it's removes all the back stack completely , and when the user clicks back in the fragment_company he closes the app.
Going to add another answer here as none of the above worked for me ... we have multiple nav graphs.
findNavController().navigate(R.id.dashboard_graph,null,NavOptions.Builder().setPopUpTo(findNavController().graph.startDestination, true).build())
This was the only way that I could successfully clear the full back stack. Google really need to make this simpler.
NOTE: Clear task is deprecated, official description is
This method is deprecated. Use setPopUpTo(int, boolean) with the id of the NavController's graph and set inclusive to true.
Old Answer
If you don't wanna go through all that fuzz in code, you can simply check Clear Task in Launch Options in properties of the action.
Edit: As of Android Studio 3.2 Beta 5, Clear Task is no longer visible in Launch Options window, but you can still use it in navigation's XML code, in action tag, by adding
app:clearTask="true"
NavController navController
=Navigation.findNavController(requireActivity(),
R.id.nav_host_fragment);// initialize navcontroller
if (navController.getCurrentDestination().getId() ==
R.id.my_current_frag) //for avoid crash
{
NavDirections action =
DailyInfoSelectorFragmentDirections.actionGoToDestionationFragment();
//for clear current fragment from stack
NavOptions options = new
NavOptions.Builder().setPopUpTo(R.id.my_current_frag, true).build();
navController.navigate(action, options);
}
I finally figure it out thanks to How to disable UP in Navigation for some fragment with the new Navigation Architecture Component?
I had to specify .setClearTask(true) as a NavOption.
mAuth.signInWithCredential(credential)
.addOnCompleteListener(getActivity(), new OnCompleteListener<AuthResult>() {
#Override
public void onComplete(#NonNull Task<AuthResult> task) {
if (task.isSuccessful()) {
Log.d(TAG, "signInWithCredential:success");
NavOptions.Builder navBuilder = new NavOptions.Builder();
NavOptions navOptions = navBuilder.setClearTask(true).build();
NavHostFragment.findNavController(LoginFragment.this).navigate(R.id.homeFragment,null,navOptions);
} else {
Log.w(TAG, "signInWithCredential:failure", task.getException());
}
}
});
use this code
navController.navigateUp();
then call new Fragment
android version 4.1.2
Here is how I am getting it done.
//here the R.id refer to the fragment one wants to pop back once pressed back from the newly navigated fragment
val navOption = NavOptions.Builder().setPopUpTo(R.id.startScorecardFragment, false).build()
//now how to navigate to new fragment
Navigation.findNavController(this, R.id.my_nav_host_fragment)
.navigate(R.id.instoredBestPractice, null, navOption)
For
// Navigation library
def nav_version = "2.3.5"
implementation "androidx.navigation:navigation-fragment-ktx:$nav_version"
implementation "androidx.navigation:navigation-ui-ktx:$nav_version"
This solution work for me
findNavController().popBackStack(R.id.<Current Fragment Id In NavGraph>, true)
findNavController().navigate(R.id.< Your Destination Fragment in NavGraph>)
In my case where I used Navigation component with NavigationView (menu drawer):
1.
mNavController.popBackStack(R.id.ID_OF_FRAGMENT_ROOT_TO_POP, true)
mNavController.navigate(
R.id.DESTINATION_ID,
null,
NavOptions.Builder()
.setPopUpTo(R.id.POP_TO_DESTINATION_ID, true)
.build()
)
I wanted to clear the stack after clicking on logout on side menu drawer!
Hope that helped someone!
You can override the back pressed of the base activity like this :
override fun onBackPressed() {
val navigationController = nav_host_fragment.findNavController()
if (navigationController.currentDestination?.id == R.id.firstFragment) {
finish()
} else if (navigationController.currentDestination?.id == R.id.secondFragment) {
// do nothing
} else {
super.onBackPressed()
}
}
Non of the solutions above works for me.
After spending hours on it, here is my solution:
Note: I have multiple nav_graphs and switching between fragments in different nav_graphs.
Define your action as below in xml:
<action
android:id="#id/your_action_id"
app:destination="#id/the_fragment_id_you_want_to_navigate_to"
app:popUpTo="#id/nav_graph_which_contains_destination_fragment"
app:popUpToInclusive="true" />
Navigate using action above from your Java/Kotlin code:
findNavController(R.id.your_nav_name)?.apply {
navigate(R.id.your_action_id)
backQueue.clear()
}
For Jetpack Compose ❤️
navHostController.navigate(Routes.HOME) {
this.popUpTo(Routes.ONBOARDING) {
this.inclusive = true
}
}
I struggled for a while to prevent the back button from going back to my start fragment, which in my case was an intro message that should only appear once.
The easy solution was to create a global action pointing to the destination that the user should stay on. You have to set app:popUpTo="..." correctly - set it to the destination you want to get popped off. In my case it was my intro message. Also set app:popUpToInclusive="true"
In my case, I am using 2 different activities that have their own respective navigation graphs. My first activity is the host for "nav_graph" and has fragments that deal with authentification and the second is the host for "nav_graph_home". Here you can see the settings I have done for nav_graph.
nav_graph example
Then back in my code for the login fragment, I have this written :
findNavController().navigate(R.id.action_logInFragment_to_nav_graph_home)
After the user logs in and they hit the back button the app will close. Remember to set the pop behavior so it pops till your current navigation graph that contains your login fragment without including it.
Edit:
After this, the up button still appears in the top bar. To avoid this behavior we need to tell the first activity which fragments are considered top level. To do this simply add in the params list of the "setupActionBarWithNavController()" method in addition to the nav host fragment an App bar configuration that contains a set of the home fragment of your first navigation graph and your second. Your code should look something like this:
class MainActivity : AppCompatActivity(R.layout.activity_main) {
private lateinit var navController: NavController
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
// Retrieve NavController from the NavHostFragment
val navHostFragment = supportFragmentManager
.findFragmentById(R.id.nav_host_fragment) as NavHostFragment
navController = navHostFragment.navController
// Set up the action bar for use with the NavController
setupActionBarWithNavController(navController, AppBarConfiguration(setOf(R.id.logInFragment,R.id.homeFragment)))
}
/**
* Handle navigation when the user chooses Up from the action bar.
*/
override fun onSupportNavigateUp(): Boolean {
return navController.navigateUp() || super.onSupportNavigateUp()
}
}
This is my first ever contribution, hope this helps.
For androidx.compose version 1.2.0+
I had a few issues with lower versions but 1.2 plus (beta at the time of writing this), works perfectly.
Better syntax for the navGraph in Compose:
navController.navigate(item.name) {
navController.graph.startDestinationRoute?.let { route ->
// use saveState = false to NOT save the state for the popped route
popUpTo(route) { saveState = true }
}
launchSingleTop = true
restoreState = true
}
I am using button to navigate to other fragments so on each button click I am doing this.
val navOptions = NavOptions.Builder().setLaunchSingleTop(true).setPopUpTo(R.id.homeFragment, false).build()
findNavController(R.id.mainNavHostFragment).navigate(R.id.destination, null, navOptions)
You can do as simple as:
getFragmentManager().popBackStack();
If you want to check the count you can do as:
getFragmentManager().getBackStackEntryCount()
I am using accessibility talkback functionality and I am facing one problem I have one bottom navigation in the parent activity and from the setting tab I am opening another fragment(inner fragment) using .add but the inner fragment view not getting focus by default
I also tried with . replace but it's not focusing by default on fragment creation.
open fragment code
val details = DetailsFragment.newInstance();
getSupportFragmentManager().setupForAccessibility()
getSupportFragmentManager().beginTransaction().add(android.R.id.content, details).commit()
and I used this extension function to not get focus on the previous fragment from this source
fun FragmentManager.setupForAccessibility() {
addOnBackStackChangedListener {
val lastFragmentWithView = fragments.lastOrNull { it.view != null }
for (fragment in fragments) {
if (fragment == lastFragmentWithView) {
fragment.view?.importantForAccessibility =
View.IMPORTANT_FOR_ACCESSIBILITY_YES
} else {
fragment.view?.importantForAccessibility =
View.IMPORTANT_FOR_ACCESSIBILITY_NO_HIDE_DESCENDANTS
}
}
}
}
in normal I show that at the start of the first fragment it's focusing top first Textview and speaking automatic but in the inner fragment it's not focusing by default so what should I do to get focus by default on the first view by default
I already try
android:focusable="true"
android:focusableInTouchMode="true"
and request focus but it's not working
Please suggest me any help would be highly appriciated
I've had the best luck using
view.sendAccessibilityEvent(AccessibilityEvent.TYPE_VIEW_FOCUSED)
on the view you want to focus, or maybe
Handler().postDelayed({
view.sendAccessibilityEvent(AccessibilityEvent.TYPE_VIEW_FOCUSED)
}, someDelayMillis)
to let the system do whatever it does, and then jump in after a moment and force a focus change.
But this might be considered bad accessibility, if it's interfering with the usual navigation, and that might be why it's so hard to get focus working consistently! It might be better to just announce the new fragment (with something like view.announceForAccessibility("new fragment")) and let the user start navigating from the top. It depends on your app, it's your call
Also you probably want to use replace for your fragment instead of add, if you add a fragment on top of an old one, TalkBack can get stuck looking at the "invisible" views on the old fragment
this is my improved code that extends from #cactustictacs
//target to specific a view
binding.getRoot().postDelayed(new Runnable() {
#Override
public void run() {
binding.textView.sendAccessibilityEvent(AccessibilityEvent.TYPE_VIEW_FOCUSED);
}
}, 300);
full: https://github.com/dotrinh-PM/AndroidTalkback
I have RecyclerView with custom RecyclerView adapter.
Each row of RecyclerView "opens"(when user clicked on it) using CardFlipAnimation(AnimatorSet).
In each row there is a button that change int value in SharedPreferences , and TextView that shows this value.
If i have opened more than one row i need dynamically change all TextViews in all rows which are opened.
NotifyDataSetChanged and etc updates data in RecyclerView great but the is a problem that they close opened rows(because for standart thay are closed and then open with AnimatorSet)
My main mission now is to understand how to update only one TextView in all opened rows and to keep them opened(dont touch AnimatorSet).
I think i can use an Observer,but i didn't know how correctly implement him.
If you any ideas please help me.
Thanks for answers
Ok, finaly i got a solution , it's a little bit ugly but it works exactly as I need.
First: I pass my RecyclerView to Adapter
...
public CardBaseAdapter(RecyclerView recyclerView,...) {
...
this.mRecyclerView = recyclerView;
....
Second: Create a method in my Adapter :
public void updateViews() {
for(int i =0;i<getItemCount();i++){
HeaderViewHolder holder = (HeaderViewHolder)recyclerView.findViewHolderForAdapterPosition(i);
if(holder!=null){
//Update views at holders
}
}
}
Third: Call this function when i need to update view
P.S. I'm not sure that this is the correct way to update view's , but it works, if you know another, good solution , post it pls