Firebase Database Crash - NullPointerException toLowerCase

Feedback Bugs
102

A complex block-based visual programming script with multiple nested conditionals and event handlers, likely created in a platform like MIT App Inventor or Scratch. (Captioned by AI)
A complex block-based visual programming script with multiple nested conditionals and event handlers, likely created in a platform like MIT App Inventor or Scratch. (Captioned by AI)1418×1780 334 KB

This approach utilizes the Web component for handling database operations.

:small_blue_diamond: Core Logic

1. Dynamic Request Builder

A procedure (test_Firebase) dynamically:

  • Constructs the Firebase URL using:
    • Bucket (Project Path)
    • Tag
  • Appends .json to match Firebase REST format
  • Chooses the request type based on a Type parameter:
    • 1 → GET
    • 2 → PUT (Store)
    • 3 → PATCH (Update)
    • 4 → DELETE

2. CRUD Operations

  • GET → Retrieves data from Firebase
  • PUT → Stores new data or overwrites existing data
  • PATCH (simulated via PUT) → Updates existing data
  • DELETE → Removes a specific tag

3. Response Handling

  • Checks responseCode = 200 for success
  • Handles responses based on request type:
    • GET
      • If data exists → JSON decoded and displayed
      • If null → shows no data
    • PUT → “Data saved successfully”
    • PATCH → “Data updated successfully”
    • DELETE
      • null → success
      • otherwise → failure
  • Displays errors when request fails

4. User Interface Flow

  • Separate buttons for:
    • Get
    • Store
    • Delete
  • Inputs:
    • Bucket (database path)
    • Tag (key)
    • Value (for storing/updating)
  • Screen switching system:
    • Toggles between Get / Put / Delete views
    • Clears inputs when switching screens

5. Data Handling

  • Ensures Firebase-compatible format:
    • Uses JSON encoding/decoding
  • Prevents crashes by:
    • Checking for "null" responses before decoding