说明：这里使用的是zxing，目前还有在更新维护，如果对速度要求高可以使用zbar，不过zbar没有更新维护了

1、gradle添加依赖

implementation 'cn.yipianfengye.android:zxing-library:2.2'

 

2、添加权限

<!-- 获取手机相机的权限 -->
    <uses-permission android:name="android.permission.CAMERA" />
    <uses-permission android:name="android.permission.FLASHLIGHT" />
    <uses-permission android:name="android.permission.VIBRATE" />

 

3、xml文件添加按钮

<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="开启相机扫描"
android:id="@+id/btn"/>

 

4、修改Activity文件

override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        //隐藏系统默认的标题
        val actionBar = supportActionBar
        actionBar?.hide()
        //初始化相机权限
        ZXingLibrary.initDisplayOpinion(this)
        btn.setOnClickListener(object : View.OnClickListener {
            override fun onClick(v: View) {
                //先判断手机版本是否在6.0以上，如果在6.0以上则需要动态申请权限
                if (Build.VERSION.SDK_INT > 22) {
                    if (ContextCompat.checkSelfPermission(
                            this@MainActivity,
                            Manifest.permission.CAMERA
                        ) != PackageManager.PERMISSION_GRANTED
                    ) {
                        //先判断有没有权限 ，没有就在这里进行权限的申请
                        ActivityCompat.requestPermissions(
                            this@MainActivity,
                            arrayOf(Manifest.permission.CAMERA), 1
                        )
                    } else {
                        //已经获取到摄像头权限，执行自定义操作
                        val intent = Intent(this@MainActivity, CaptureActivity::class.java)
                        startActivityForResult(intent, 1)
                    }
                } else {
                    //系统版本在6.0之下，不需要动态获取权限。
                    val intent = Intent(this@MainActivity, CaptureActivity::class.java)
                    startActivityForResult(intent, 1)
                }
            }
        })
    }

    //获取手机相机权限
    override fun onRequestPermissionsResult(
        requestCode: Int,
        permissions: Array<String>,
        grantResults: IntArray
    ) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults)
        if (requestCode == 1) {
            if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                val intent = Intent(this, CaptureActivity::class.java)
                startActivityForResult(intent, 1)
            } else {
                Toast.makeText(this@MainActivity, "请打开相机权限", Toast.LENGTH_SHORT).show()
            }
        }
    }

    //处理扫描结果
    override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
        super.onActivityResult(requestCode, resultCode, data)
        if (resultCode == Activity.RESULT_OK) {
            if (data != null) {
                val bundle = data.extras ?: return
                if (bundle.getInt(CodeUtils.RESULT_TYPE) == CodeUtils.RESULT_SUCCESS) {
                    //获取到扫描结果
                    val result = bundle.getString(CodeUtils.RESULT_STRING)
                    if (result != null) {
                        Log.d("res:", result)
                    }
                }
            }
        }
    }