Android - 二维码生成器 API

Question

我正在尝试从我的应用程序生成一些 QR，但我看到有很多类型的 QR，例如联系人、Wi-Fi 等。我想知道是否有免费的 API 或库来实现这一点，我已经看到有些网站已经在生成它，所以我想知道 Android 是否有任何 API 或库可以使用。

我检查过的：

http://goqr.me/api

中兴

但我不确定是否有一个功能可以说好的，我想要一个联系人的二维码，这样我就可以添加它的所有信息。

Answer 1

QR code generation using ZXing

Add the following ZXing core dependency in your app level build.gradle file.

implementation 'com.google.zxing:core:3.4.0'

Sample code to generate a 512x512 px WiFi QR code. You can set the resultant Bitmap in an ImageView.

fun getQrCodeBitmap(ssid: String, password: String): Bitmap {
    val qrCodeContent = "WIFI:S:$ssid;T:WPA;P:$password;;"
    val hints = hashMapOf<EncodeHintType, Int>().also { it[EncodeHintType.MARGIN] = 1 } // Make the QR code buffer border narrower
    val bits = QRCodeWriter().encode(qrCodeContent, BarcodeFormat.QR_CODE, size, size, hints)
    val size = 512 //pixels
    return Bitmap.createBitmap(size, size, Bitmap.Config.RGB_565).also {
        for (x in 0 until size) {
            for (y in 0 until size) {
                it.setPixel(x, y, if (bits[x, y]) Color.BLACK else Color.WHITE)
            }
        }
    }
}

To generate other types of QR code such as SMS, VCard etc. you can check out this helpful ZXing Wiki.

Scanning QR code using Google Mobile Vision API

Add the following GMS dependency to your app level build.gradle.

implementation 'com.google.android.gms:play-services-vision:20.1.2'

Step 1: Setup the Barcode processor callback.

private val processor = object : Detector.Processor<Barcode> {
    
    override fun receiveDetections(detections: Detector.Detections<Barcode>?) {
        detections?.apply {
            if (detectedItems.isNotEmpty()) {
                val qr = detectedItems.valueAt(0)
                // Parses the WiFi format for you and gives the field values directly
                // Similarly you can do qr.sms for SMS QR code etc.
                qr.wifi?.let { 
                    Log.d(TAG, "SSID: ${it.ssid}, Password: ${it.password}")
                }
            }
        }
    }

    override fun release() {}
} 

Step 2: Setup the BardcodeDetector with the barcode processor callback and add it to the CameraSource as follows. Don't forget to check for Manifest.permission.CAMERA at runtime and add the same to your AndroidManifest.xml.

private fun setupCameraView() {
    if (ContextCompat.checkSelfPermission(requireContext(), android.Manifest.permission.CAMERA) == PackageManager.PERMISSION_GRANTED) {
        BarcodeDetector.Builder(requireContext()).setBarcodeFormats(QR_CODE).build().apply {
            setProcessor(processor)
            if (!isOperational) {
                Log.d(TAG, "Native QR detector dependencies not available!")
                return
            }
            cameraSource = CameraSource.Builder(requireContext(), this).setAutoFocusEnabled(true)
                .setFacing(CameraSource.CAMERA_FACING_BACK).build()
        }
    } else {
        // Request camers permission from user
        // Add <uses-permission android:name="android.permission.CAMERA" /> to AndroidManifest.xml
    }
}

Step 3: Add a SurfaceView to your layout to host your CameraSource.

<SurfaceView
    android:id="@+id/surfaceView"
    android:layout_width="match_parent"
    android:layout_height="match_parent" /> 

Step 4: Create a callback to start and stop the CameraSource when the surface is created / destroyed.

private val callback = object : SurfaceHolder.Callback {

    override fun surfaceCreated(holder: SurfaceHolder) {
        // Ideally, you should check the condition somewhere 
        // before inflating the layout which contains the SurfaceView
        if (isPlayServicesAvailable(requireActivity()))
            cameraSource?.start(holder)
    } 

    override fun surfaceDestroyed(holder: SurfaceHolder) {
        cameraSource?.stop()
    }

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


// Helper method to check if Google Play Services are up to-date on the phone
fun isPlayServicesAvailable(activity: Activity): Boolean {
    val code = GoogleApiAvailability.getInstance().isGooglePlayServicesAvailable(applicationContext)
    if (code != ConnectionResult.SUCCESS) {
        GoogleApiAvailability.getInstance().getErrorDialog(activity, code, code).show()
        return false
    }
    return true
}

Step 5: Link everything together with the lifecycle methods.

// Create camera source and attach surface view callback to surface holder
override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
    return inflater.inflate(R.layout.fragment_camera_sheet, container, false).also {
        setupCamera()
        it.surfaceView.holder.addCallback(callback)
    }
}

// Free up camera source resources
override fun onDestroy() {
    super.onDestroy()
    cameraSource?.release()
}

Answer 2

QRCodeWriterU 可以使用类和函数使用 Zxing 生成 QR encode()，其中第一个参数是 QR 保存的实际数据。自定义示例：

val qrCodeData: String = "data"
val bitMatrix = QRCodeWriter().encode(
    String(
        qrCodeData.toByteArray(charset(CHARSET)),
        Charset.forName(CHARSET)
    ),
    BarcodeFormat.QR_CODE,
    size,
    size,
    hints
)

哪里hints也是这个库的一部分，可以在 中找到EncodeHintType。

然后你必须生成一个Bitmap可以在例如中显示的ImageView。

val bitmap = Bitmap.createBitmap(
    size,
    size,
    Bitmap.Config.ARGB_8888
)

for (x in 0 until size) {
    for (y in 0 until size) {
        val fillColor = if (bitMatrix[x, y]) Color.BLACK else Color.WHITE
        bitmap.setPixel(x, y, fillColor) // <-- color ur QR to default black and white
    }
}

Answer 3

对于 vCard 我可以推荐这个How to create vcf file using java?

ZXing正确的方式[2021更新]

依赖性Gradle Scripts/build.gradle(Module:app)

implementation 'com.journeyapps:zxing-android-embedded:4.3.0'

代码

import android.util.Log;
import android.graphics.Bitmap;
import com.google.zxing.BarcodeFormat;
import com.google.zxing.WriterException;
import com.journeyapps.barcodescanner.BarcodeEncoder;

public static Bitmap generateQR(String content, int size) {
    Bitmap bitmap = null;
    try {
        BarcodeEncoder barcodeEncoder = new BarcodeEncoder();
        bitmap = barcodeEncoder.encodeBitmap(content,
            BarcodeFormat.QR_CODE, size, size);
    } catch (WriterException e) {
        Log.e("generateQR()", e.getMessage());
    }
    return bitmap;
}

更多详细信息请参见：dx.dragan.ba/qr-creation-android/