Delete Firebase Data | Android App Development | Lecture#47 | Hive Learners

Hi dear Hive Learners, I hope you all are well. In lecture 46 we learn how to process the retrieved data from the firebase real-time database and then we add this data in a model class and use this model class in an adapter to show the data in a listview. We also successfully run the app and it was working like charm. Today we will learn how to delete data from the firebase database by using the button in the listview. So let's get started.

GitHub Link

Use this GitHub project to clone into your directory. The following lecture will update it so you will never miss the latest code. Happy Coding!

What Should I Learn

• How to delete data from Firebase real-time database

Assignment

• Delete data on a button click

Procedure

We already has a delete button in our listview and also have a listener for it. We need to get to know what child we are deleting and write the code according to it. We will also implement the complete listener to sow delete successful or failed messages on the screen. We implement the listener interface in the Fragment When we move the code. That interface will not work in the Fragment so we will use the onclicListenere in the Adapter class.

Now we need to first get the child that we want to delete on the button click. We want the parent node and the child inside it can be deleted automatically. We are using the Firebase Auth id as the parent key. So we can get and use the Firebase uid. Using parent Firebase uid will not allow us to store more than one data for a user. We need to use the PushKey and we will do it in the next lecture. This time we are simply learning how to delete the data in firebase.

We can implement the task complete listener to show the success or failure message. I add the new data in the database so we can save the data via uid.

We hardcode the username value which is why we get the My Account in the username field. Here we now have two children in the sending reference.

Now press the delete button on this child and check if the data is deleted from the database or not.

Data is deleted but we have not notify the adapter that data is changed so we need to do so. We also need to change the Listener type from Single Listener to a regular Listener so that the database can get the change and update the POJO class. I also change the code in the Transfers_Fragment to store the account_number correctly.

Let's try to add and delete the item again.

Thank You