For now, I have a working ListView that successfully loads every “parent” object in the ListView, retrieving the parent attributes and showing them in every element. Due to I am trying to follow Android’s Model-View-ViewModel architecture patterns, I am using RoomDb, a Repository class and a…
Tag: android-room
For some reason my Android room DAO insert doesn’t work on Temi Robot
For some reason even after following some parts of the guide, I wasn’t able to insert a new entry to my database. retrival is okay. I don’t really want to do the respitory and viewmodel boilerplates as mentioned in the guide I have put the relevant dependencies in build.gradle already. I am using …
Room database RawQuery() is not work on “IN” and “NOT IN” clause
I have my one table like UserTable. // Now in My MainActivity.class file, I have use following code: My query is running in normal database, but when I was pass array of user ids then, in @RawQuery() method of dao class is not supported for “IN” clause used in where condition “WHERE userId I…
Implement favorites list with room library
I want to implement a list of the user’s favorite news for a news app using the room library, but the app crashes Thank you for your help (: DataBase: I could not put the code, I used the photo: enter image description here Dao: AdapterNews: Erro: enter image description here Answer Try to use thread or…
Dao Room database. How to SUM all the amounts and view it as a TextView?
I am creating a simple expence tracker. I can add items to the database and view them in a recyclerview. But when I try to SUM all values from a column, it only return 0 instead of the sum of all the values. First of all, here’s the column which values I am trying to sum together. And here is
Android room how to increment count field and updating specific row fields
I have the following schema I am implementing for counting button taps for a user . For example if the the user clicks on apple button I would like to store the type as primary key which would be a unique entry followed by the count for the number of times the user taps on apple button and for each
Relations between Room Tables Android
I am developping a chat app. I have two Entities And In MessageDao I want to get Contact phone correponding to the contact_id in MessageItem Answer You have three ways you can do this. 1) You can use a POJO with an @Embedded and an @Relation in which case you return MessageItem’s with the Contact e.g. :…
Merging multiple LiveData sources?
To make it easier to visualize my problem I drew the following: I am using a RoomDatabase, a Repository, a Viewmodel and Livedata. Areas have a 1 to n relationship with Gateways and Gateways a 1 to n relationship with Items. I created both an AreaWithGateways entity and a GatewayWithItems entity. Items can mo…
Room database not created
I’m trying to develop an app with Room. The project is in java. This is my first time using Room. I’ve followed the documentation and created class with @Database, @Dao & @Entity. However when I run the app, it throws the following exception. Can someone please help me figure out what am I doi…
Room Database. Insert sucessfull but no data found
I’ve got a simple Room database setup as seen below: Entity Class My Dao Interface: My Database: Finally my ViewModel: And my Activity where I print the results: As you can see from the code, I first try creating a default user in my database. If the insert is sucessfull, which it is cause I always ente…