show/hide brightness seekbar from camera callback

app/src/main/kotlin/com/simplemobiletools/flashlight/activities/MainActivity.kt

@@ -19,6 +19,7 @@ import com.simplemobiletools.commons.models.FAQItem
 import com.simplemobiletools.flashlight.BuildConfig
 import com.simplemobiletools.flashlight.R
 import com.simplemobiletools.flashlight.extensions.config
+import com.simplemobiletools.flashlight.helpers.CameraTorchListener
 import com.simplemobiletools.flashlight.helpers.MIN_BRIGHTNESS_LEVEL
 import com.simplemobiletools.flashlight.helpers.MyCameraImpl
 import com.simplemobiletools.flashlight.models.Events
@@ -54,10 +55,6 @@ class MainActivity : SimpleActivity() {
 
         flashlight_btn.setOnClickListener {
             mCameraImpl!!.toggleFlashlight()
-            if (mCameraImpl?.supportsBrightnessControl() == true) {
-                brightness_bar.beInvisibleIf(brightness_bar.isVisible)
-                stroboscope_bar.beInvisible()
-            }
         }
 
         sos_btn.setOnClickListener {
@@ -184,7 +181,13 @@ class MainActivity : SimpleActivity() {
     }
 
     private fun setupCameraImpl() {
-        mCameraImpl = MyCameraImpl.newInstance(this)
+        mCameraImpl = MyCameraImpl.newInstance(this, object : CameraTorchListener {
+            override fun onTorchEnabled(isEnabled: Boolean) {
+                if (mCameraImpl?.supportsBrightnessControl() == true) {
+                    brightness_bar.beVisibleIf(isEnabled)
+                }
+            }
+        })
         if (config.turnFlashlightOn) {
             mCameraImpl!!.enableFlashlight()
         }
@@ -233,7 +236,6 @@ class MainActivity : SimpleActivity() {
             sos_btn.setTextColor(if (isSOSRunning) getProperPrimaryColor() else getContrastColor())
         } else if (mCameraImpl!!.toggleStroboscope()) {
             stroboscope_bar.beInvisibleIf(stroboscope_bar.isVisible())
-            brightness_bar.beInvisible()
             changeIconColor(if (stroboscope_bar.isVisible()) getProperPrimaryColor() else getContrastColor(), stroboscope_btn)
         }
     }

app/src/main/kotlin/com/simplemobiletools/flashlight/helpers/CameraTorchListener.kt

@@ -0,0 +1,5 @@
+package com.simplemobiletools.flashlight.helpers
+
+interface CameraTorchListener {
+    fun onTorchEnabled(isEnabled:Boolean)
+}

app/src/main/kotlin/com/simplemobiletools/flashlight/helpers/MyCameraImpl.kt

@@ -1,5 +1,6 @@
 package com.simplemobiletools.flashlight.helpers
 
+import android.annotation.SuppressLint
 import android.content.Context
 import android.graphics.SurfaceTexture
 import android.hardware.Camera
@@ -14,7 +15,7 @@ import com.simplemobiletools.flashlight.extensions.updateWidgets
 import com.simplemobiletools.flashlight.models.Events
 import org.greenrobot.eventbus.EventBus
 
-class MyCameraImpl(val context: Context) {
+class MyCameraImpl private constructor(val context: Context, private val cameraTorchListener: CameraTorchListener?) {
     var stroboFrequency = 1000L
 
     companion object {
@@ -40,7 +41,7 @@ class MyCameraImpl(val context: Context) {
         @Volatile
         private var isSOSRunning = false
 
-        fun newInstance(context: Context) = MyCameraImpl(context)
+        fun newInstance(context: Context, cameraTorchListener: CameraTorchListener? = null) = MyCameraImpl(context, cameraTorchListener)
     }
 
     init {
@@ -140,9 +141,10 @@ class MyCameraImpl(val context: Context) {
         }
     }
 
+    @SuppressLint("NewApi")
     private fun setupMarshmallowCamera() {
         if (marshmallowCamera == null) {
-            marshmallowCamera = PostMarshmallowCamera(context)
+            marshmallowCamera = PostMarshmallowCamera(context, cameraTorchListener)
         }
     }
 
@@ -209,6 +211,7 @@ class MyCameraImpl(val context: Context) {
 
         val mainRunnable = Runnable { stateChanged(true) }
         Handler(context.mainLooper).post(mainRunnable)
+        marshmallowCamera?.initialize()
     }
 
     private fun disableFlashlight() {
@@ -254,6 +257,7 @@ class MyCameraImpl(val context: Context) {
 
         isFlashlightOn = false
         shouldStroboscopeStop = true
+        marshmallowCamera?.cleanUp()
     }
 
     private val stroboscope = Runnable {

app/src/main/kotlin/com/simplemobiletools/flashlight/helpers/PostMarshmallowCamera.kt

@@ -1,22 +1,32 @@
 package com.simplemobiletools.flashlight.helpers
 
-import android.annotation.TargetApi
 import android.content.Context
 import android.hardware.camera2.CameraCharacteristics
 import android.hardware.camera2.CameraManager
 import android.os.Build
 import android.os.Handler
+import androidx.annotation.RequiresApi
 import com.simplemobiletools.commons.extensions.showErrorToast
 import com.simplemobiletools.commons.helpers.isTiramisuPlus
 import com.simplemobiletools.flashlight.extensions.config
 import com.simplemobiletools.flashlight.models.Events
 import org.greenrobot.eventbus.EventBus
 
-internal class PostMarshmallowCamera constructor(val context: Context) {
+@RequiresApi(Build.VERSION_CODES.M)
+internal class PostMarshmallowCamera(
+    private val context: Context,
+    private val cameraTorchListener: CameraTorchListener? = null,
+) {
 
     private val manager = context.getSystemService(Context.CAMERA_SERVICE) as CameraManager
     private var cameraId: String? = null
 
+    private val torchCallback = object : CameraManager.TorchCallback() {
+        override fun onTorchModeChanged(cameraId: String, enabled: Boolean) {
+            cameraTorchListener?.onTorchEnabled(enabled)
+        }
+    }
+
     init {
         try {
             cameraId = manager.cameraIdList[0] ?: "0"
@@ -25,7 +35,6 @@ internal class PostMarshmallowCamera constructor(val context: Context) {
         }
     }
 
-    @TargetApi(Build.VERSION_CODES.M)
     fun toggleMarshmallowFlashlight(enable: Boolean) {
         try {
             manager.setTorchMode(cameraId!!, enable)
@@ -69,4 +78,12 @@ internal class PostMarshmallowCamera constructor(val context: Context) {
         }
         return brightnessLevel
     }
+
+    fun initialize() {
+        manager.registerTorchCallback(torchCallback, Handler(context.mainLooper))
+    }
+
+    fun cleanUp() {
+        manager.unregisterTorchCallback(torchCallback)
+    }
 }