1 /*
<lambda>null2  * Copyright 2022 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package androidx.camera.integration.view
18 
19 import android.graphics.RectF
20 import android.os.Bundle
21 import android.view.LayoutInflater
22 import android.view.View
23 import android.view.ViewGroup
24 import android.widget.Button
25 import android.widget.ToggleButton
26 import androidx.camera.core.CameraSelector.DEFAULT_BACK_CAMERA
27 import androidx.camera.core.CameraSelector.DEFAULT_FRONT_CAMERA
28 import androidx.camera.core.ImageAnalysis.COORDINATE_SYSTEM_VIEW_REFERENCED
29 import androidx.camera.core.impl.utils.executor.CameraXExecutors.mainThreadExecutor
30 import androidx.camera.mlkit.vision.MlKitAnalyzer
31 import androidx.camera.view.LifecycleCameraController
32 import androidx.camera.view.PreviewView
33 import androidx.fragment.app.Fragment
34 import com.google.mlkit.vision.barcode.BarcodeScanner
35 import com.google.mlkit.vision.barcode.BarcodeScanning
36 
37 /** Fragment for testing MLKit integration. */
38 class MlKitFragment : Fragment() {
39 
40     private lateinit var cameraController: LifecycleCameraController
41     private lateinit var previewView: PreviewView
42     private lateinit var overlayView: OverlayView
43     private lateinit var toggle: ToggleButton
44     private var barcodeScanner: BarcodeScanner? = null
45 
46     override fun onCreateView(
47         inflater: LayoutInflater,
48         container: ViewGroup?,
49         savedInstanceState: Bundle?
50     ): View? {
51         // Set up UI.
52         val view = inflater.inflate(R.layout.mlkit_view, container, false)
53         previewView = view.findViewById(R.id.preview_view)
54         overlayView = view.findViewById(R.id.overlay_view)
55         toggle = view.findViewById(R.id.toggle_camera)
56         toggle.setOnCheckedChangeListener { _, _ -> updateCameraOrientation() }
57         previewView.implementationMode = PreviewView.ImplementationMode.COMPATIBLE
58         // This button resets the pipeline. This is for testing when the detector is closed,
59         // MlKitAnalyzer handles it correctly.
60         view.findViewById<Button>(R.id.restart).setOnClickListener { clearAndSetAnalyzer() }
61 
62         // Set up CameraX.
63         cameraController = LifecycleCameraController(requireContext())
64         cameraController.bindToLifecycle(viewLifecycleOwner)
65         previewView.controller = cameraController
66         clearAndSetAnalyzer()
67 
68         // Update states to match UI.
69         updateCameraOrientation()
70         return view
71     }
72 
73     override fun onDestroyView() {
74         super.onDestroyView()
75         barcodeScanner?.close()
76     }
77 
78     private fun updateCameraOrientation() {
79         cameraController.cameraSelector =
80             if (toggle.isChecked) DEFAULT_BACK_CAMERA else DEFAULT_FRONT_CAMERA
81     }
82 
83     private fun clearAndSetAnalyzer() {
84         barcodeScanner?.close()
85         barcodeScanner = BarcodeScanning.getClient()
86 
87         cameraController.clearImageAnalysisAnalyzer()
88         val scanner = barcodeScanner!!
89         cameraController.setImageAnalysisAnalyzer(
90             mainThreadExecutor(),
91             MlKitAnalyzer(
92                 listOf(scanner),
93                 COORDINATE_SYSTEM_VIEW_REFERENCED,
94                 mainThreadExecutor()
95             ) { result ->
96                 val barcodes = result.getValue(scanner)
97                 if (barcodes != null && barcodes.size > 0) {
98                     overlayView.setTileRect(RectF(barcodes[0].boundingBox))
99                     overlayView.invalidate()
100                 }
101             }
102         )
103     }
104 }
105