我希望我的应用程序可以通过摄像头识别条形码。使用Android SDK是否可行?
类似这样的实现方式: 条码扫描
我希望我的应用程序可以通过摄像头识别条形码。使用Android SDK是否可行?
类似这样的实现方式: 条码扫描
虽然SDK中没有内置此功能,但您可以使用Zxing库。它是免费、开源且基于Apache许可证。
2016年的建议是使用Barcode API,该API也可以离线使用。
随着Google Play服务的最新版本v7.8发布,您现在可以访问新的移动视觉API。这可能是现在实现条形码扫描的最方便的方式,而且它还可以离线工作。
条形码API可以在设备上任意方向的实时检测条形码。它还可以同时检测多个条形码。
它可以读取以下条形码格式:
- 1D条形码:EAN-13、EAN-8、UPC-A、UPC-E、Code-39、Code-93、Code-128、ITF、Codabar
- 2D条形码:QR码、Data Matrix、PDF-417、Aztec
它会自动解析QR码、Data Matrix、PDF-417和Aztec值,支持以下格式:
- URL
- 联系人信息(VCARD等)
- 日历事件
- 电子邮件
- 电话
- SMS
- ISBN
- WiFi
- 地理位置(纬度和经度)
- AAMVA驾驶执照/身份证明
这里是使用相机 API 的示例代码
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.util.SparseArray;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import java.io.IOException;
import com.google.android.gms.vision.CameraSource;
import com.google.android.gms.vision.Detector;
import com.google.android.gms.vision.Frame;
import com.google.android.gms.vision.barcode.Barcode;
import com.google.android.gms.vision.barcode.BarcodeDetector;
public class MainActivity extends AppCompatActivity {
TextView barcodeInfo;
SurfaceView cameraView;
CameraSource cameraSource;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
cameraView = (SurfaceView) findViewById(R.id.camera_view);
barcodeInfo = (TextView) findViewById(R.id.txtContent);
BarcodeDetector barcodeDetector =
new BarcodeDetector.Builder(this)
.setBarcodeFormats(Barcode.CODE_128)//QR_CODE)
.build();
cameraSource = new CameraSource
.Builder(this, barcodeDetector)
.setRequestedPreviewSize(640, 480)
.build();
cameraView.getHolder().addCallback(new SurfaceHolder.Callback() {
@Override
public void surfaceCreated(SurfaceHolder holder) {
try {
cameraSource.start(cameraView.getHolder());
} catch (IOException ie) {
Log.e("CAMERA SOURCE", ie.getMessage());
}
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
cameraSource.stop();
}
});
barcodeDetector.setProcessor(new Detector.Processor<Barcode>() {
@Override
public void release() {
}
@Override
public void receiveDetections(Detector.Detections<Barcode> detections) {
final SparseArray<Barcode> barcodes = detections.getDetectedItems();
if (barcodes.size() != 0) {
barcodeInfo.post(new Runnable() { // Use the post method of the TextView
public void run() {
barcodeInfo.setText( // Update the TextView
barcodes.valueAt(0).displayValue
);
}
});
}
}
});
}
}
主活动的布局文件activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.example.gateway.cameraapibarcode.MainActivity">
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical">
<SurfaceView
android:layout_width="640px"
android:layout_height="480px"
android:layout_centerVertical="true"
android:layout_alignParentLeft="true"
android:id="@+id/camera_view"/>
<TextView
android:text=" code reader"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/txtContent"/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Process"
android:id="@+id/button"
android:layout_alignParentTop="true"
android:layout_alignParentStart="true" />
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/imgview"/>
</LinearLayout>
</RelativeLayout>
build.gradle(Module:app)
在依赖项中添加compile 'com.google.android.gms:play-services:7.8.+'
以下是示例代码: 我的应用程序使用了ZXing条形码扫描器。
您需要这两个类: IntentIntegrator 和 IntentResult
调用扫描器(例如 OnClickListener,OnMenuItemSelected...),“PRODUCT_MODE”- 它可以扫描标准的1D条形码(您可以添加更多):
IntentIntegrator.initiateScan(this,
"Warning",
"ZXing Barcode Scanner is not installed, download?",
"Yes", "No",
"PRODUCT_MODE");
获得条形码作为结果:
public void onActivityResult(int requestCode, int resultCode, Intent intent) {
switch (requestCode) {
case IntentIntegrator.REQUEST_CODE:
if (resultCode == Activity.RESULT_OK) {
IntentResult intentResult =
IntentIntegrator.parseActivityResult(requestCode, resultCode, intent);
if (intentResult != null) {
String contents = intentResult.getContents();
String format = intentResult.getFormatName();
this.elemQuery.setText(contents);
this.resume = false;
Log.d("SEARCH_EAN", "OK, EAN: " + contents + ", FORMAT: " + format);
} else {
Log.e("SEARCH_EAN", "IntentResult je NULL!");
}
} else if (resultCode == Activity.RESULT_CANCELED) {
Log.e("SEARCH_EAN", "CANCEL");
}
}
}
contents 包含条形码号码。
应用模块:
implementation 'com.google.zxing:core:3.2.1'
implementation 'com.journeyapps:zxing-android-embedded:3.2.0@aar'
AndroidManifest.xml
<uses-permission android:name="android.permission.CAMERA" />
<uses-feature android:name="android.hardware.camera" />
<uses-feature android:name="android.hardware.camera.autofocus"/>
MainActivity.java
public class MainActivity extends AppCompatActivity {
Button BarCode;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
BarCode = findViewById(R.id.button_barcode);
final Activity activity = this;
BarCode.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
IntentIntegrator intentIntegrator = new IntentIntegrator(activity);
intentIntegrator.setDesiredBarcodeFormats(intentIntegrator.ALL_CODE_TYPES);
intentIntegrator.setBeepEnabled(false);
intentIntegrator.setCameraId(0);
intentIntegrator.setPrompt("SCAN");
intentIntegrator.setBarcodeImageEnabled(false);
intentIntegrator.initiateScan();
}
});
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
IntentResult Result = IntentIntegrator.parseActivityResult(requestCode , resultCode ,data);
if(Result != null){
if(Result.getContents() == null){
Log.d("MainActivity" , "cancelled scan");
Toast.makeText(this, "cancelled", Toast.LENGTH_SHORT).show();
}
else {
Log.d("MainActivity" , "Scanned");
Toast.makeText(this,"Scanned -> " + Result.getContents(), Toast.LENGTH_SHORT).show();
}
}
else {
super.onActivityResult(requestCode , resultCode , data);
}
}
}
https://firebase.google.com/docs/ml-kit/read-barcodes?authuser=0
你可以通过此链接高效读取条形码。Firebase Barcode scanning API已被弃用。
您可以使用Google的ML Kit来识别和解码条形码,无需使用Firebase。
在gradle(app)中添加
implementation 'com.google.mlkit:barcode-scanning:17.1.1'
我在parseActivityForResult参数方面遇到了问题。但是我已经让它工作了:
package JMA.BarCodeScanner;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
public class JMABarcodeScannerActivity extends Activity {
Button captureButton;
TextView tvContents;
TextView tvFormat;
Activity activity;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
activity = this;
captureButton = (Button)findViewById(R.id.capture);
captureButton.setOnClickListener(listener);
tvContents = (TextView)findViewById(R.id.tvContents);
tvFormat = (TextView)findViewById(R.id.tvFormat);
}
public void onActivityResult(int requestCode, int resultCode, Intent intent)
{
switch (requestCode)
{
case IntentIntegrator.REQUEST_CODE:
if (resultCode == Activity.RESULT_OK)
{
IntentResult intentResult = IntentIntegrator.parseActivityResult(requestCode, resultCode, intent);
if (intentResult != null)
{
String contents = intentResult.getContents();
String format = intentResult.getFormatName();
tvContents.setText(contents.toString());
tvFormat.setText(format.toString());
//this.elemQuery.setText(contents);
//this.resume = false;
Log.d("SEARCH_EAN", "OK, EAN: " + contents + ", FORMAT: " + format);
} else {
Log.e("SEARCH_EAN", "IntentResult je NULL!");
}
}
else if (resultCode == Activity.RESULT_CANCELED) {
Log.e("SEARCH_EAN", "CANCEL");
}
}
}
private View.OnClickListener listener = new View.OnClickListener() {
@Override
public void onClick(View v) {
IntentIntegrator integrator = new IntentIntegrator(activity);
integrator.initiateScan();
}
};
}
Activity的布局:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<Button
android:id="@+id/capture"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Take a Picture"/>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/tvContents"
android:layout_width="wrap_content"
android:layout_height="wrap_content"/>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/tvFormat"
android:layout_width="wrap_content"
android:layout_height="wrap_content"/>
</LinearLayout>