Android开发教程二维码扫描功能

二维码扫描大一点的app都有的功能，因为扫一下真的很方便

一、思路：

用zxing库

二、效果图：

看视频更加直观点：

三、关键代码：

class FCaptureActivity : AppCompatActivity(), SurfaceHolder.Callback {
    // 相机控制
    private var cameraManager: MyCameraManager? = null
    private var handler: CaptureActivityHandler? = null
    private var viewfinderView: ViewfinderView? = null
    private var hasSurface: Boolean = false
    private var decodeFormats: Collection<BarcodeFormat>? = null
    private val decodeHints: Map<DecodeHintType, *>? = null
    private var characterSet: String? = null
    private var REQUEST_CODE: Int = 1001

    private lateinit var open :CheckBox

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.find_activity_zxing)
        val window = window
        window.addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON)
        initUI()

    }

     fun initUI() {

         open = findViewById(R.id.open)

        open.setOnCheckedChangeListener { _, isChecked ->
            when (isChecked) {
                true -> openFlashLight()
                else -> closeFlashLight()
            }
        }
    }




    fun getViewfinderView(): ViewfinderView? {
        return viewfinderView
    }

    fun getHandler(): Handler? {
        return handler
    }

    fun getCameraManager(): MyCameraManager? {
        return cameraManager
    }

    fun drawViewfinder() {
        viewfinderView?.drawViewfinder()
    }

    override fun onResume() {
        super.onResume()
        // CameraManager必须在这里初始化，而不是在onCreate()中。
        // 这是必须的，因为当我们第一次进入时需要显示帮助页，我们并不想打开Camera,测量屏幕大小
        // 当扫描框的尺寸不正确时会出现bug
        cameraManager = MyCameraManager(this)
        viewfinderView = findViewById(R.id.viewfinder_view)
        viewfinderView?.setCameraManager(cameraManager)
        viewfinderView?.setWord(true)
        handler = null
        val surfaceView = findViewById<SurfaceView>(R.id.preview_view)
        val surfaceHolder = surfaceView.holder
        if (hasSurface) {
            // activity在paused时但不会stopped,因此surface仍旧存在；
            // surfaceCreated()不会调用，因此在这里初始化camera
            initCamera(surfaceHolder)
        } else {
            // 重置callback，等待surfaceCreated()来初始化camera
            surfaceHolder.addCallback(this)
        }
        decodeFormats = null
        characterSet = null
    }

    override fun onPause() {
        if (handler != null) {
            handler?.quitSynchronously()
            handler = null
        }
        cameraManager?.closeDriver()
        if (!hasSurface) {
            val surfaceView = findViewById<SurfaceView>(R.id.preview_view)
            val surfaceHolder = surfaceView.holder
            surfaceHolder.removeCallback(this)
        }
        super.onPause()
    }

    /**
     * 初始化Camera
     *
     * @param surfaceHolder
     */
    private fun initCamera(surfaceHolder: SurfaceHolder?) {
        if (surfaceHolder == null) {
            throw IllegalStateException("No SurfaceHolder provided")
        }
        if (cameraManager!!.isOpen) {
            return
        }
        try {
            // 打开Camera硬件设备
            cameraManager?.openDriver(surfaceHolder)
            // 创建一个handler来打开预览，并抛出一个运行时异常
            if (handler == null) {
                handler = CaptureActivityHandler(this, decodeFormats, decodeHints, characterSet, cameraManager)
            }
        } catch (ioe: Exception) {

        }

    }


    /**
     * 扫描成功，处理反馈信息
     *
     * @param rawResult
     * @param barcode
     * @param scaleFactor
     */
    fun handleDecode(result: Result?, barcode: Bitmap?, scaleFactor: Float?) {
        Log.d("handleDecode", "结果${result?.text}")
        Toast.makeText(this,"结果 ${result?.text}",Toast.LENGTH_LONG).show()
//        if (!TextUtils.isEmpty(result?.text)) {
//            if (result?.text!!.indexOf("scan/regID=") != -1) {//扫码登录
//
//            } else if (result?.text!!.indexOf("scan/pcLogin") != -1){ //pc官网登录
//
//            }  else {
//                //基本不会出现这种情况
//                showToastDialog("温馨提示", "无法识别该图片，请用相机扫描", "确认")
//
//            }
//
//        }
    }


    /**
     * 开灯
     */
    private fun openFlashLight() {
        if (!cameraManager!!.isOpen) {
            return
        }
        val parameter = cameraManager?.camera?.parameters
        parameter?.flashMode = FLASH_MODE_TORCH
        cameraManager?.camera?.parameters = parameter
    }

    /**
     * 关闭闪光灯
     */
    private fun closeFlashLight() {
        if (!cameraManager!!.isOpen) {
            return
        }
        val parameter = cameraManager?.camera?.parameters
        parameter?.flashMode = FLASH_MODE_OFF
        cameraManager?.camera?.parameters = parameter
    }

    override fun surfaceCreated(holder: SurfaceHolder) {
        if (!hasSurface) {
            hasSurface = true
            initCamera(holder)
        }
    }

    override fun surfaceChanged(holder: SurfaceHolder, format: Int, width: Int, height: Int) {
    }

    override fun surfaceDestroyed(holder: SurfaceHolder) {
        hasSurface = false
    }

}

四、项目demo源码结构图

有问题或者需要完整源码的私信我