android-room

问题 I'm trying out the new coroutine's flow, my goal is to make a simple repository that can fetch data from a web api and save it to db, also return a flow from the db. I'm using room and firebase as the web api, now everything seems pretty straight forward until i try to pass errors coming from the api to the ui. Since i get a flow from the database which only contains the data and no state, what is the correct approach to give it a state (like loading, content, error) by combining it with the

问题 I'm trying out the new coroutine's flow, my goal is to make a simple repository that can fetch data from a web api and save it to db, also return a flow from the db. I'm using room and firebase as the web api, now everything seems pretty straight forward until i try to pass errors coming from the api to the ui. Since i get a flow from the database which only contains the data and no state, what is the correct approach to give it a state (like loading, content, error) by combining it with the

问题 The RecyclerView when launched shows all the data instead of showing data of a specific id. I am using Room database and as I understand the problem is when the ViewModel is getting initialized, the repository gets all the colors.. I couldn't figure out how to code in Repository, so that when the ViewModel is initialized it only gets data of specific ids instead of all data. In one of the answers in stack it mentions something about using "SwitchMap"...but I am new to Android so not sure if

问题 The RecyclerView when launched shows all the data instead of showing data of a specific id. I am using Room database and as I understand the problem is when the ViewModel is getting initialized, the repository gets all the colors.. I couldn't figure out how to code in Repository, so that when the ViewModel is initialized it only gets data of specific ids instead of all data. In one of the answers in stack it mentions something about using "SwitchMap"...but I am new to Android so not sure if

问题 The RecyclerView when launched shows all the data instead of showing data of a specific id. I am using Room database and as I understand the problem is when the ViewModel is getting initialized, the repository gets all the colors.. I couldn't figure out how to code in Repository, so that when the ViewModel is initialized it only gets data of specific ids instead of all data. In one of the answers in stack it mentions something about using "SwitchMap"...but I am new to Android so not sure if

问题 Over the past days I have been getting comfortable with Android Architecture Components and I've been mostly interested in the Paging Library for handling and displaying lists of data from a remote source. For the best UX it is better to load data first into the database, in this case Room then display it in a recyclerview using the pagingLibrary and adapters. My concern is this, lets say an api has 1000s of records or a twitter feed even and all this data has to pass through the db then to

问题 Over the past days I have been getting comfortable with Android Architecture Components and I've been mostly interested in the Paging Library for handling and displaying lists of data from a remote source. For the best UX it is better to load data first into the database, in this case Room then display it in a recyclerview using the pagingLibrary and adapters. My concern is this, lets say an api has 1000s of records or a twitter feed even and all this data has to pass through the db then to

问题 I am migrating my old Android project to new standards, I got stuck in between room database , not able to find how to execute these 2 SQLite commands using room database . I have 2 queries which are working in a nested manner, so to achieve the same result using room is there any possibility. default public ArrayList getOfflineRoomsAndObjectsByParentIds(String parentId, String site_id, Context context) { databaseHandler = new DatabaseHandler(context); Cursor cr = null; ArrayList<Room>

问题 Im working with Android's Room Database and am having some big problems understanding how to: When I add a Person to the database, it adds all its variables e.g. List<Shoe> , List<Pet> etc. to the database as well. Create relations such that when I retrieve a Person , all its fields are retrieved e.g Pet, Shoe, Shirt etc. (Not sure what type of query that is) Perform simple query e.g. Retrieve Person where shoe.name = "boot" ; I know you must use Foreign Key relationships with list of objects

问题 Im working with Android's Room Database and am having some big problems understanding how to: When I add a Person to the database, it adds all its variables e.g. List<Shoe> , List<Pet> etc. to the database as well. Create relations such that when I retrieve a Person , all its fields are retrieved e.g Pet, Shoe, Shirt etc. (Not sure what type of query that is) Perform simple query e.g. Retrieve Person where shoe.name = "boot" ; I know you must use Foreign Key relationships with list of objects