Package com.cmput301w23t09.qrhunter.scanqr.camera

Class CameraController

java.lang.Object

com.cmput301w23t09.qrhunter.scanqr.camera.CameraController

Direct Known Subclasses:

CameraLocationPhotoController, CameraScannerController

public abstract class CameraController
extends java.lang.Object

Manages Camera preview and capture using Google's CameraX library https://developer.android.com/training/camerax (Used ChatGPT to convert Kotlin to Java)

Extended in subclasses to add functionality, such as QRCode scanning and photo taking (location photos)

See Also:

CameraScannerController, CameraLocationPhotoController

Field Summary

Fields

Modifier and Type	Field	Description
static java.lang.String[]	CAMERA_PERMISSIONS
protected java.util.concurrent.ExecutorService	cameraExecutor
protected androidx.fragment.app.Fragment	fragment
protected androidx.camera.view.PreviewView	previewView
static int	REQUEST_CODE_PERMISSIONS

Constructor Summary

Constructors

Constructor	Description
CameraController(androidx.fragment.app.Fragment fragment, androidx.camera.view.PreviewView previewView)	Creates a basic CameraController that displays its preview to a view.

Method Summary

Modifier and Type	Method	Description
boolean	cameraPermissionsGranted()	Checks if all required permissions are granted
void	onDestroy()	Shut down the camera when it's no longer needed
protected abstract void	setupCamera(com.google.common.util.concurrent.ListenableFuture<androidx.camera.lifecycle.ProcessCameraProvider> cameraProviderFuture)	Adds in the camera's functionality
void	startCamera()	Starts the camera and binds it's preview to the PreviewView UI element.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

cameraExecutor

protected java.util.concurrent.ExecutorService cameraExecutor

fragment

protected androidx.fragment.app.Fragment fragment

previewView

protected androidx.camera.view.PreviewView previewView

REQUEST_CODE_PERMISSIONS

public static final int REQUEST_CODE_PERMISSIONS

See Also:

Constant Field Values

CAMERA_PERMISSIONS

public static final java.lang.String[] CAMERA_PERMISSIONS

Constructor Detail

CameraController

public CameraController(androidx.fragment.app.Fragment fragment,
                        androidx.camera.view.PreviewView previewView)

Creates a basic CameraController that displays its preview to a view.

Parameters:

fragment - The fragment that uses the camera.

previewView - The UI element in fragment to show camera preview on.

Method Detail

startCamera

public void startCamera()

Starts the camera and binds it's preview to the PreviewView UI element.

setupCamera

protected abstract void setupCamera(com.google.common.util.concurrent.ListenableFuture<androidx.camera.lifecycle.ProcessCameraProvider> cameraProviderFuture)
                             throws java.util.concurrent.ExecutionException,
                                    java.lang.InterruptedException

Adds in the camera's functionality

Parameters:

cameraProviderFuture - The camera's provider object

Throws:

java.util.concurrent.ExecutionException - if setup fails

java.lang.InterruptedException - if setup fails

onDestroy

public void onDestroy()

Shut down the camera when it's no longer needed

cameraPermissionsGranted

public boolean cameraPermissionsGranted()

Checks if all required permissions are granted

Returns:

True if every permission under CameraController.REQUIRED_PERMISSIONS is granted