Android

- If a camera was already set initialized it would initialize it again
- A redesign on how to handle that situation might be better
- This prevents the crash and works in one specific use case

integration/boofcv-android/src/main/java/boofcv/android/fragments/CameraProcessFragment.kt

@@ -49,7 +49,7 @@ import kotlin.math.roundToInt
  */
 abstract class CameraProcessFragment : Fragment() {
     /** Used to adjust how it captures images. Affects quality and speed */
-    private var captureRequestTemplateType = CameraDevice.TEMPLATE_RECORD
+    protected var captureRequestTemplateType = CameraDevice.TEMPLATE_RECORD
 
     /** Data structures for each camera and capture surface */
     protected val cameraDevices = HashMap<CameraID, DeviceSurfaces>()
@@ -92,7 +92,7 @@ abstract class CameraProcessFragment : Fragment() {
                 for (reader in cam.readers) {
                     reader.close()
                 }
-            } catch( e: IllegalStateException) {
+            } catch (e: IllegalStateException) {
                 Log.e(TAG, "Failed to close a camera", e)
             }
         }
@@ -262,7 +262,7 @@ abstract class CameraProcessFragment : Fragment() {
      * Starts a [CameraCaptureSession] and returns the configured session (as the result of the
      * suspend coroutine
      */
-    private suspend fun createCaptureSession(cameraID: CameraID, camera: DeviceSurfaces):
+    protected suspend fun createCaptureSession(cameraID: CameraID, camera: DeviceSurfaces):
             CameraCaptureSession = suspendCoroutine { cont ->
 
         // Configure it so it can point a camera inside a multi-camera system

integration/boofcv-android/src/main/java/boofcv/android/fragments/ImageProcessingFragment.kt

@@ -195,6 +195,12 @@ abstract class ImageProcessingFragment : CameraProcessFragment() {
                 initializeCameraCoordinates(cameraID, right - left, bottom - top, rotation)
             }
 
+            // If the device already exists, don't create it again and crash
+            // NOTE: If the resolution changed this might not be the correct behavior
+            val device = cameraDevices[cameraID]
+            if (device != null && device.session != null)
+                return@addOnLayoutChangeListener
+
             // Add image processor for computer vision stream
             val reader = addCameraProcessor(
                 cameraID,
@@ -319,8 +325,8 @@ abstract class ImageProcessingFragment : CameraProcessFragment() {
             setWillNotDraw(false)
         }
 
-        override fun onDraw(canvas: Canvas?) {
-            onDrawFrame(this, canvas!!)
+        override fun onDraw(canvas: Canvas) {
+            onDrawFrame(this, canvas)
         }
 
         override fun surfaceCreated(holder: SurfaceHolder) {}