Deep links in Android Kotlin - Mini App: Build & Ship

Build: DeepLinkDemoScreen

This screen handles deep links to show a message passed in the URL.

Target UI

-------------------------
| Deep Link Demo        |
|-----------------------|
| Message:              |
| [                    ]|
|                       |
| (Open app via deep link)|
-------------------------

Handle deep links with scheme 'myapp' and host 'showmessage'

Extract 'msg' query parameter from the deep link URL

Display the extracted message on the screen

Show a default message if no deep link or no message parameter

Starter Code

Android Kotlin

package com.example.deeplinkdemo

import android.content.Intent
import android.net.Uri
import android.os.Bundle
import android.widget.TextView
import androidx.appcompat.app.AppCompatActivity

class DeepLinkDemoScreen : AppCompatActivity() {
    private lateinit var messageTextView: TextView

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_deep_link_demo_screen)

        messageTextView = findViewById(R.id.messageTextView)

        // TODO: Handle the incoming intent for deep link
    }
}

Task 1

Task 2

Task 3

Task 4

Solution

Android Kotlin

package com.example.deeplinkdemo

import android.content.Intent
import android.net.Uri
import android.os.Bundle
import android.widget.TextView
import androidx.appcompat.app.AppCompatActivity

class DeepLinkDemoScreen : AppCompatActivity() {
    private lateinit var messageTextView: TextView

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_deep_link_demo_screen)

        messageTextView = findViewById(R.id.messageTextView)

        val data: Uri? = intent?.data
        if (data != null && data.scheme == "myapp" && data.host == "showmessage") {
            val message = data.getQueryParameter("msg") ?: "No message found"
            messageTextView.text = message
        } else {
            messageTextView.text = "Welcome! Open this screen via a deep link."
        }
    }
}

We check if the intent has data (a Uri). Then we verify the scheme is 'myapp' and the host is 'showmessage' to confirm it's our deep link. We extract the 'msg' query parameter from the Uri and display it in the TextView. If no deep link or message is found, we show a default welcome message.

Final Result

Completed Screen

-------------------------
| Deep Link Demo        |
|-----------------------|
| Message:              |
| Hello from deep link! |
|                       |
| (Open app via deep link)|
-------------------------

When user opens the app via a deep link like myapp://showmessage?msg=Hello%20from%20deep%20link!, the message text updates to 'Hello from deep link!'

If app is opened normally, the message shows the default welcome text

Stretch Goal

Add support for deep links with a path parameter instead of query parameter, e.g., myapp://showmessage/HelloWorld

💡 Hint

Use Uri.getPathSegments() to extract the message from the path segments