Skip to main content

Taking Screenshots Programmatically

It is possible to take a screenshot of your Android application programmatically.

Basic Usage​

There are possibly many methods that you can use to take a screenshot programmatically. In this document, we are going to take a look at 2 methods used by the wonderful Sentry team in their sentry-java open-source project:

  1. PixelCopy API. This API is added in API level 24.
  2. View.draw() method. This API is added in API level 1.

You can take a look directly at ScreenshotUtils.java file inside sentry-java repository to see how Sentry team utilizes these methods to take a screenshot programmatically. However, to simplify this document, we have recreated a simpler version of the utility file below:

SimpleScreenshotUtil.kt
package com.hanmajid.androidnotebook

import android.app.Activity
import android.content.Context
import android.graphics.Bitmap
import android.graphics.Canvas
import android.os.Build
import android.os.Handler
import android.os.HandlerThread
import android.util.Log
import android.view.PixelCopy

/**
 * Screenshot-related utility object.
 */
object SimpleScreenshotUtil {

    /**
     * Take a screenshot of current [Activity].
     */
    fun takeScreenshot(
        activity: Activity,
    ) {
        val view = activity.window.decorView.rootView
        val resultBitmap = Bitmap.createBitmap(view.width, view.height, Bitmap.Config.ARGB_8888);

        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            val thread = HandlerThread("MyThread").apply {
                start()
            }
            val handler = Handler(thread.looper)
            PixelCopy.request(
                activity.window,
                resultBitmap,
                {
                    if (it == PixelCopy.SUCCESS) {
                        saveScreenshot(
                            activity = activity,
                            bitmap = resultBitmap,
                            filename = "my-screenshot-pixel-copy.png",
                        )
                    } else {
                        Log.i("TAG", "ERROR $it")
                        // Handle error.
                    }
                },
                handler,
            )
        } else {
            val canvas = Canvas(resultBitmap)
            activity.runOnUiThread {
                try {
                    view.draw(canvas)
                    saveScreenshot(
                        activity = activity,
                        bitmap = resultBitmap,
                        filename = "my-screenshot-canvas.png",
                    )
                } catch (e: Throwable) {
                    Log.e("TAG", e.message, e)
                    // Handle error.
                }
            }
        }
    }

    /**
     * Save the taken screenshot [bitmap] to Internal Storage.
     */
    private fun saveScreenshot(
        activity: Activity,
        bitmap: Bitmap,
        filename: String,
    ) {
        activity.openFileOutput(filename, Context.MODE_PRIVATE)
            .use { outputStream ->
                bitmap.compress(Bitmap.CompressFormat.PNG, 0, outputStream)
            }
    }
}

To use SimpleScreenshotUtil.kt object, simply call takeScreenshot method inside your Activity:

MainActivity.kt
package com.hanmajid.androidnotebook

import android.os.Bundle
import androidx.activity.ComponentActivity
import androidx.activity.compose.setContent
import androidx.compose.foundation.layout.Column
import androidx.compose.foundation.layout.fillMaxSize
import androidx.compose.material3.Button
import androidx.compose.material3.MaterialTheme
import androidx.compose.material3.Surface
import androidx.compose.material3.Text
import androidx.compose.runtime.Composable
import androidx.compose.ui.Modifier
import androidx.compose.ui.tooling.preview.Preview
import com.hanmajid.androidnotebook.ui.theme.MyApplicationTheme

class MainActivity : ComponentActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContent {
            MyApplicationTheme {
                // A surface container using the 'background' color from the theme
                Surface(
                    modifier = Modifier.fillMaxSize(),
                    color = MaterialTheme.colorScheme.background
                ) {
                    Column {
                        Greeting("Android")
                        Button(onClick = {
                            SimpleScreenshotUtil.takeScreenshot(this@MainActivity)
                        }) {
                            Text("Take Screenshot")
                        }
                    }
                }
            }
        }
    }
}

@Composable
fun Greeting(name: String, modifier: Modifier = Modifier) {
    Text(
        text = "Hello $name!",
        modifier = modifier
    )
}

@Preview(showBackground = true)
@Composable
fun GreetingPreview() {
    MyApplicationTheme {
        Greeting("Android")
    }
}

After takeScreenshot() method is called, the image will be saved inside the app's Internal Storage:

References​

Last updated on