recheck the previews aspect ratio on resolution change

app/src/main/kotlin/com/simplemobiletools/camera/Preview.kt

@@ -132,10 +132,7 @@ class Preview : ViewGroup, SurfaceHolder.Callback, MediaScannerConnection.OnScan
             mMaxZoom = mParameters!!.maxZoom
             mZoomRatios = mParameters!!.zoomRatios
             mSupportedPreviewSizes = mParameters!!.supportedPreviewSizes.sortedByDescending { it.width * it.height }
-            mIsSixteenToNine = isSixteenToNine()
-            requestLayout()
-            invalidate()
-            mSetupPreviewAfterMeasure = true
+            refreshPreview()
 
             val focusModes = mParameters!!.supportedFocusModes
             if (focusModes.contains(Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE))
@@ -163,6 +160,13 @@ class Preview : ViewGroup, SurfaceHolder.Callback, MediaScannerConnection.OnScan
         return true
     }
 
+    private fun refreshPreview() {
+        mIsSixteenToNine = isSixteenToNine()
+        mSetupPreviewAfterMeasure = true
+        requestLayout()
+        invalidate()
+    }
+
     private fun isSixteenToNine(): Boolean {
         val selectedSize = getSelectedResolution()
         val selectedRatio = Math.abs(selectedSize.width / selectedSize.height.toFloat())
@@ -287,8 +291,6 @@ class Preview : ViewGroup, SurfaceHolder.Callback, MediaScannerConnection.OnScan
         mCanTakePicture = true
     }
 
-    fun getSupportedVideoSizes(): List<Camera.Size> = mParameters!!.supportedVideoSizes ?: mParameters!!.supportedPreviewSizes
-
     private fun focusArea(takePictureAfter: Boolean) {
         if (mCamera == null)
             return
@@ -332,9 +334,12 @@ class Preview : ViewGroup, SurfaceHolder.Callback, MediaScannerConnection.OnScan
     }
 
     fun showChangeResolutionDialog() {
+        val oldResolution = getSelectedResolution()
         if (mCamera != null) {
             ChangeResolutionDialog(mActivity, config.lastUsedCamera == Camera.CameraInfo.CAMERA_FACING_BACK, mCamera!!) {
-
+                if (oldResolution != getSelectedResolution()) {
+                    refreshPreview()
+                }
             }
         }
     }

app/src/main/kotlin/com/simplemobiletools/camera/dialogs/ChangeResolutionDialog.kt

@@ -21,6 +21,7 @@ class ChangeResolutionDialog(val activity: SimpleActivity, val isBackCamera: Boo
 
         AlertDialog.Builder(activity)
                 .setPositiveButton(R.string.ok, null)
+                .setOnDismissListener { callback() }
                 .create().apply {
             activity.setupDialogStuff(view, this, if (isBackCamera) R.string.back_camera else R.string.front_camera)
         }