android-architecture-components

问题 I am a bit confused on how the Navigation component fits in the app behavior. It all looks nice and shiny in tutorials where you don't do things too complex but when implementing in real app, things seem different. Before Navigation Before implementing navigation I had to manually run fragment transactions. In order to do this, my fragment would implement an interface onFragmentAction which passed a bundle to the main Activity and in the activity based on the actions, replace the current

问题 I'm using navigation component with bottom navigation view in my app. Problem was when I return back to top-level destinations from child destination, recyclerView not showing any elements. nav_graph_main: <?xml version="1.0" encoding="utf-8"?> <navigation xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto" xmlns:tools="http://schemas.android.com/tools" android:id="@+id/nav_graph_main" app:startDestination="@id/navigation_stats">

问题 I'm using LiveData to fetch data from a server and observe it. My onChanged() method just gets called the first time, and does not get called when data in the server gets updated. UserFragment: UserViewModel userViewModel = ViewModelProviders.of(this).get(UserViewModel.class); userViewModel.getUser().observe(this, new Observer<User>() { @Override public void onChanged(User user) { //Set UI } }); UserViewModel: public class UserViewModel extends AndroidViewModel { private LiveData<User> user;

问题 Using Android Architecture's Navigation component, I have the following navigation graph -> [Home] -> [Articles List] -> [Specific Article] I also have a deeplink to [Specific Article] . When it is opened, navigating up currently goes to [Home] . I'd like to synthesise a backstack such that navigating up instead goes back to [Articles List] (and then on to [Home] if navigating again). What is the Navigation way of doing this? 回答1: Per the NavDeepLinkBuilder documentation, Navigation uses the

问题 Using Android Architecture's Navigation component, I have the following navigation graph -> [Home] -> [Articles List] -> [Specific Article] I also have a deeplink to [Specific Article] . When it is opened, navigating up currently goes to [Home] . I'd like to synthesise a backstack such that navigating up instead goes back to [Articles List] (and then on to [Home] if navigating again). What is the Navigation way of doing this? 回答1: Per the NavDeepLinkBuilder documentation, Navigation uses the

问题 I have a case where I have BottomNavigationView where fragments are shown/hidden instead of adding/replacing, therefore they do not go through their lifecycle every time. Fragment 1 is observing one database table, Fragment 2 is observing a different one. My goal is to call the onChanged of Fragment 2 when onChanged of Fragment 1 is called. A stupid and naive solution that worked was to set up the observer of Fragment 1 in Fragment 2 and inside it call another observer: mFragment1ViewModel1

问题 I am very new using Android architecture components, so I decided to base my application using GithubBrowserSample to achieve many of my use cases. But i have the problem that i don´t know what is the correct way to share viewmodels between fragments with this approach. I want to share the view model because i have a fragment with a viewpager with 2 fragments that need to observe data of the parent fragment view model I used this before to achieve it, based on google's documentation override

问题 I want to implement Android Architecture Component with AppWidgetProvider. I'm not sure to map properly Widget LifeCycle to LifeCycle events. I created a BaseAppWidgetProvider to be extented by my widgets: /** * Base class for {@link BaseAppWidgetProvider} to manage {@link Lifecycle} */ public abstract class BaseAppWidgetProvider extends AppWidgetProvider implements LifecycleOwner { private final AppWidgetProviderLifecycleDispatcher mDispatcher = new AppWidgetProviderLifecycleDispatcher(this)

问题 I want to implement Android Architecture Component with AppWidgetProvider. I'm not sure to map properly Widget LifeCycle to LifeCycle events. I created a BaseAppWidgetProvider to be extented by my widgets: /** * Base class for {@link BaseAppWidgetProvider} to manage {@link Lifecycle} */ public abstract class BaseAppWidgetProvider extends AppWidgetProvider implements LifecycleOwner { private final AppWidgetProviderLifecycleDispatcher mDispatcher = new AppWidgetProviderLifecycleDispatcher(this)

问题 I've trying to integrate the architecture components in my app, viz Pagination, LiveData, ViewModel. Room is already integrated and tested before so I can return a DataSource.Factory<Integer, DbEntity> from my DAO class. This is my code for creating LiveData of PagedList: PagedList.Config pagedListConfig = (new PagedList.Config.Builder()).setEnablePlaceholders(true) .setPrefetchDistance(5) .setPageSize(10) .setInitialLoadSizeHint(10) .build(); LiveData<PagedList<DbEntity>> dbEntities = new