Custom events in Firebase - Step-by-Step Execution

Process Flow - Custom events

User triggers action

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Create custom event object

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Send event to Firebase Analytics

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Firebase records event

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Event data available in Analytics dashboard

This flow shows how a user action creates a custom event, which is sent to Firebase Analytics and recorded for later analysis.

Execution Sample

Firebase

firebase.analytics().logEvent('purchase', {item: 'sword', price: 10});

This code sends a custom event named 'purchase' with details about the item and price to Firebase Analytics.

Process Table

Step	Action	Event Name	Event Parameters	Result
1	User triggers purchase	purchase	{item: 'sword', price: 10}	Event object created
2	Call logEvent	purchase	{item: 'sword', price: 10}	Event sent to Firebase
3	Firebase receives event	purchase	{item: 'sword', price: 10}	Event recorded in Analytics
4	Analytics dashboard updates	purchase	{item: 'sword', price: 10}	Event visible for analysis
5	No more events	-	-	Execution ends

💡 No more events to send; process completes

Status Tracker

Variable	Start	After Step 1	After Step 2	After Step 3	Final
eventName	undefined	purchase	purchase	purchase	purchase
eventParams	undefined	{item: 'sword', price: 10}	{item: 'sword', price: 10}	{item: 'sword', price: 10}	{item: 'sword', price: 10}
eventSent	false	false	true	true	true
eventRecorded	false	false	false	true	true

Key Moments - 3 Insights

Why do we need to specify event parameters like item and price?

Event parameters provide extra details about the event, making the data more useful in Analytics. See execution_table step 1 and 3 where parameters are included.

What happens if we call logEvent with the same event name multiple times?

Each call sends a separate event instance to Firebase. Analytics records all occurrences separately for accurate tracking.

Does the event get recorded immediately after calling logEvent?

No, the event is sent asynchronously. Execution_table step 2 shows sending, step 3 shows recording, which may happen shortly after.

Visual Quiz - 3 Questions

Look at the execution_table, what is the eventName after Step 2?

A purchase

B undefined

C logEvent

D firebase

💡 Hint

Check the eventName column in execution_table row for Step 2

At which step does Firebase record the event in Analytics?

A Step 1

B Step 2

C Step 3

D Step 4

💡 Hint

Look at the Result column in execution_table for when eventRecorded becomes true

If we add a new parameter 'currency: USD' to the event, how does variable_tracker change?

A eventName will change to 'currency'

B eventParams will include currency: USD after Step 1

C eventSent becomes false

D eventRecorded becomes false

💡 Hint

Check eventParams values in variable_tracker after Step 1

Concept Snapshot

Custom events in Firebase let you track specific user actions.
Use firebase.analytics().logEvent('eventName', {params}) to send events.
Events include a name and optional parameters with details.
Firebase records events asynchronously and shows them in Analytics.
Use descriptive names and parameters for better insights.

Full Transcript

Custom events in Firebase start when a user triggers an action. The app creates an event object with a name and parameters. Then it calls firebase.analytics().logEvent to send the event. Firebase receives and records the event asynchronously. Finally, the event appears in the Analytics dashboard for review. Parameters add useful details to events. Multiple calls with the same event name create separate records. Events are not recorded instantly but shortly after sending.