Take photos

Note: This page refers to the Camera class, which is deprecated. We recommend using CameraX or, for specific use cases, Camera2. Both CameraX and Camera2 support Android 5.0 (API level 21) and higher.

This lesson teaches how to capture a photo by delegating the work to another camera app on the device. (If you'd rather build your own camera functionality, see Controlling the camera.)

Suppose you are implementing a crowd-sourced weather service that makes a global weather map by blending together pictures of the sky taken by devices running your client app. Integrating photos is only a small part of your application. You want to take photos with minimal fuss, not reinvent the camera. Happily, most Android-powered devices already have at least one camera application installed. In this lesson, you learn how to make it take a picture for you.

Request the camera feature

If an essential function of your application is taking pictures, then restrict its visibility on Google Play to devices that have a camera. To advertise that your application depends on having a camera, put a <uses-feature> tag in your manifest file:

<manifest...>
<uses-featureandroid:name="android.hardware.camera"
android:required="true"/>
...
</manifest>

If your application uses, but does not require a camera in order to function, instead set android:required to false. In doing so, Google Play will allow devices without a camera to download your application. It's then your responsibility to check for the availability of the camera at runtime by calling hasSystemFeature(PackageManager.FEATURE_CAMERA_ANY) . If a camera is not available, you should then disable your camera features.

Get the thumbnail

If the simple feat of taking a photo is not the culmination of your app's ambition, then you probably want to get the image back from the camera application and do something with it.

The Android Camera application encodes the photo in the return Intent delivered to onActivityResult() as a small Bitmap in the extras, under the key "data". The following code retrieves this image and displays it in an ImageView .

overridefunonActivityResult(requestCode:Int,resultCode:Int,data:Intent?){
if(requestCode==REQUEST_IMAGE_CAPTURE && resultCode==RESULT_OK){
valimageBitmap=data.extras.get("data")asBitmap
imageView.setImageBitmap(imageBitmap)
}
}

@Override
protectedvoidonActivityResult(intrequestCode,intresultCode,Intentdata){
if(requestCode==REQUEST_IMAGE_CAPTURE && resultCode==RESULT_OK){
Bundleextras=data.getExtras();
BitmapimageBitmap=(Bitmap)extras.get("data");
imageView.setImageBitmap(imageBitmap);
}
}

Note: This thumbnail image from "data" might be good for an icon, but not a lot more. Dealing with a full-sized image takes a bit more work.

Save the full-size photo

The Android Camera application saves a full-size photo if you give it a file to save into. You must provide a fully qualified file name where the camera app should save the photo.

Generally, any photos that the user captures with the device camera should be saved on the device in the public external storage so they are accessible by all apps. The proper directory for shared photos is provided by getExternalStoragePublicDirectory() , with the DIRECTORY_PICTURES argument. The directory provided by this method is shared among all apps. On Android 9 (API level 28) and lower, reading and writing to this directory requires the READ_EXTERNAL_STORAGE and WRITE_EXTERNAL_STORAGE permissions, respectively:

<manifest...>
<uses-permissionandroid:name="android.permission.READ_EXTERNAL_STORAGE"/>
<uses-permissionandroid:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
...
</manifest>

On Android 10 (API level 29) and higher, the proper directory for sharing photos is the MediaStore.Images table. You don't need to declare any storage permissions, as long as your app only needs to access the photos that the user took using your app.

However, if you'd like the photos to remain private to your app only, you can instead use the directory provided by Context.getExternalFilesDir() . On Android 4.3 and lower, writing to this directory also requires the WRITE_EXTERNAL_STORAGE permission. Beginning with Android 4.4, the permission is no longer required because the directory is not accessible by other apps, so you can declare the permission should be requested only on the lower versions of Android by adding the maxSdkVersion attribute:

<manifest...>
<uses-permissionandroid:name="android.permission.WRITE_EXTERNAL_STORAGE"
android:maxSdkVersion="28"/>
...
</manifest>

Note: Files you save in the directories provided by getExternalFilesDir() or getFilesDir() are deleted when the user uninstalls your app.

Once you decide the directory for the file, you need to create a collision-resistant file name. You may wish also to save the path in a member variable for later use. Here's an example solution in a method that returns a unique file name for a new photo using a date-time stamp. (This example assumes you are calling the method from inside a Context.)

lateinitvarcurrentPhotoPath:String
@Throws(IOException::class)
privatefuncreateImageFile():File{
// Create an image file name
valtimeStamp:String=SimpleDateFormat("yyyyMMdd_HHmmss").format(Date())
valstorageDir:File=getExternalFilesDir(Environment.DIRECTORY_PICTURES)
returnFile.createTempFile(
"JPEG_${timeStamp}_",/* prefix */
".jpg",/* suffix */
storageDir/* directory */
).apply{
// Save a file: path for use with ACTION_VIEW intents
currentPhotoPath=absolutePath
}
}

StringcurrentPhotoPath;
privateFilecreateImageFile()throwsIOException{
// Create an image file name
StringtimeStamp=newSimpleDateFormat("yyyyMMdd_HHmmss").format(newDate());
StringimageFileName="JPEG_"+timeStamp+"_";
FilestorageDir=getExternalFilesDir(Environment.DIRECTORY_PICTURES);
Fileimage=File.createTempFile(
imageFileName,/* prefix */
".jpg",/* suffix */
storageDir/* directory */
);
// Save a file: path for use with ACTION_VIEW intents
currentPhotoPath=image.getAbsolutePath();
returnimage;
}

With this method available to create a file for the photo, you can now create and invoke the Intent like this:

privatefundispatchTakePictureIntent(){
Intent(MediaStore.ACTION_IMAGE_CAPTURE).also{takePictureIntent->
// Ensure that there's a camera activity to handle the intent
takePictureIntent.resolveActivity(packageManager)?.also{
// Create the File where the photo should go
valphotoFile:File? =try{
createImageFile()
}catch(ex:IOException){
// Error occurred while creating the File
...
null
}
// Continue only if the File was successfully created
photoFile?.also{
valphotoURI:Uri=FileProvider.getUriForFile(
this,
"com.example.android.fileprovider",
it
)
takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT,photoURI)
startActivityForResult(takePictureIntent,REQUEST_IMAGE_CAPTURE)
}
}
}
}

privatevoiddispatchTakePictureIntent(){
IntenttakePictureIntent=newIntent(MediaStore.ACTION_IMAGE_CAPTURE);
// Ensure that there's a camera activity to handle the intent
if(takePictureIntent.resolveActivity(getPackageManager())!=null){
// Create the File where the photo should go
FilephotoFile=null;
try{
photoFile=createImageFile();
}catch(IOExceptionex){
// Error occurred while creating the File
...
}
// Continue only if the File was successfully created
if(photoFile!=null){
UriphotoURI=FileProvider.getUriForFile(this,
"com.example.android.fileprovider",
photoFile);
takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT,photoURI);
startActivityForResult(takePictureIntent,REQUEST_IMAGE_CAPTURE);
}
}
}

Note: We are using getUriForFile(Context, String, File) which returns a content:// URI. For more recent apps targeting Android 7.0 (API level 24) and higher, passing a file:// URI across a package boundary causes a FileUriExposedException . Therefore, we now present a more generic way of storing images using a FileProvider .

Now, you need to configure the FileProvider . In your app's manifest, add a provider to your application:

<application>
...
<provider
android:name="androidx.core.content.FileProvider"
android:authorities="com.example.android.fileprovider"
android:exported="false"
android:grantUriPermissions="true">
<meta-data
android:name="android.support.FILE_PROVIDER_PATHS"
android:resource="@xml/file_paths"></meta-data>
</provider>
...
</application>

Make sure that the authorities string matches the second argument to getUriForFile(Context, String, File) . In the meta-data section of the provider definition, you can see that the provider expects eligible paths to be configured in a dedicated resource file, res/xml/file_paths.xml. Here is the content required for this particular example:

<?xmlversion="1.0"encoding="utf-8"?>
<pathsxmlns:android="http://schemas.android.com/apk/res/android">
<external-files-pathname="my_images"path="Pictures"/>
</paths>

The path component corresponds to the path that is returned by getExternalFilesDir() when called with Environment.DIRECTORY_PICTURES . Make sure that you replace com.example.package.name with the actual package name of your app. Also, checkout the documentation of FileProvider for an extensive description of path specifiers that you can use besides external-path.

Add the photo to a gallery

When you create a photo through an intent, you should know where your image is located, because you said where to save it in the first place. For everyone else, perhaps the easiest way to make your photo accessible is to make it accessible from the system's Media Provider.

Note: If you saved your photo to the directory provided by getExternalFilesDir() , the media scanner cannot access the files because they are private to your app.

The following example method demonstrates how to invoke the system's media scanner to add your photo to the Media Provider's database, making it available in the Android Gallery application and to other apps.

privatefungalleryAddPic(){
Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE).also{mediaScanIntent->
valf=File(currentPhotoPath)
mediaScanIntent.data=Uri.fromFile(f)
sendBroadcast(mediaScanIntent)
}
}

privatevoidgalleryAddPic(){
IntentmediaScanIntent=newIntent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE);
Filef=newFile(currentPhotoPath);
UricontentUri=Uri.fromFile(f);
mediaScanIntent.setData(contentUri);
this.sendBroadcast(mediaScanIntent);
}

Decode a scaled image

Managing multiple full-sized images can be tricky with limited memory. If you find your application running out of memory after displaying just a few images, you can dramatically reduce the amount of dynamic heap used by expanding the JPEG into a memory array that's already scaled to match the size of the destination view. The following example method demonstrates this technique.

privatefunsetPic(){
// Get the dimensions of the View
valtargetW:Int=imageView.width
valtargetH:Int=imageView.height
valbmOptions=BitmapFactory.Options().apply{
// Get the dimensions of the bitmap
inJustDecodeBounds=true
BitmapFactory.decodeFile(currentPhotoPath,bmOptions)
valphotoW:Int=outWidth
valphotoH:Int=outHeight
// Determine how much to scale down the image
valscaleFactor:Int=Math.max(1,Math.min(photoW/targetW,photoH/targetH))
// Decode the image file into a Bitmap sized to fill the View
inJustDecodeBounds=false
inSampleSize=scaleFactor
inPurgeable=true
}
BitmapFactory.decodeFile(currentPhotoPath,bmOptions)?.also{bitmap->
imageView.setImageBitmap(bitmap)
}
}

privatevoidsetPic(){
// Get the dimensions of the View
inttargetW=imageView.getWidth();
inttargetH=imageView.getHeight();
// Get the dimensions of the bitmap
BitmapFactory.OptionsbmOptions=newBitmapFactory.Options();
bmOptions.inJustDecodeBounds=true;
BitmapFactory.decodeFile(currentPhotoPath,bmOptions);
intphotoW=bmOptions.outWidth;
intphotoH=bmOptions.outHeight;
// Determine how much to scale down the image
intscaleFactor=Math.max(1,Math.min(photoW/targetW,photoH/targetH));
// Decode the image file into a Bitmap sized to fill the View
bmOptions.inJustDecodeBounds=false;
bmOptions.inSampleSize=scaleFactor;
bmOptions.inPurgeable=true;
Bitmapbitmap=BitmapFactory.decodeFile(currentPhotoPath,bmOptions);
imageView.setImageBitmap(bitmap);
}