Android实现扫描二维码功能

本文实例为大家分享了Android实现扫描二维码的具体代码，供大家参考，具体内容如下

1.效果图：

2.引用公共库:builder.radle，在app目录下

implementation 'com.google.android.gms:play-services-maps:17.0.0'
implementation 'com.google.android.gms:play-services-vision:19.0.0'
implementation 'com.google.android.gms:auth-api-impl:11.6.0'

3.清单文件，拍照权限申请

<uses-permission android:name="android.permission.CAMERA" /

4.主界面：

package com.example.administrator.testz;
import android.Manifest;
import android.app.Activity;
import android.content.ActivityNotFoundException;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.content.pm.PackageManager;
import android.content.res.Resources;
import android.net.Uri;
import android.os.Bundle;
import android.os.PersistableBundle;
import android.os.Vibrator;
import android.util.Log;
import android.util.SparseArray;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.widget.TextView;
import com.google.android.gms.vision.CameraSource;
import com.google.android.gms.vision.Detector;
import com.google.android.gms.vision.barcode.Barcode;
import com.google.android.gms.vision.barcode.BarcodeDetector;
import java.io.IOException;
import java.util.ArrayList;
import androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;
import androidx.core.app.ActivityCompat;
public class MainActivity extends AppCompatActivity {
SurfaceView surfaceView;
CameraSource cameraSource;
TextView qrCodeText;
BarcodeDetector barcodeDetector;
public static ArrayList<String  scannList;
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
surfaceView = (SurfaceView) findViewById(R.id.qrView);
qrCodeText = (TextView) findViewById(R.id.tv);
scannList = new ArrayList< ();
barcodeDetector = new BarcodeDetector.Builder(this)
.setBarcodeFormats(Barcode.QR_CODE)
.build();
cameraSource = new CameraSource.Builder(this, barcodeDetector)
.setRequestedPreviewSize(640, 480)
.setAutoFocusEnabled(true)
.build();
surfaceView.getHolder().addCallback(new SurfaceHolder.Callback() {
@Override
public void surfaceCreated(SurfaceHolder holder) {
if (ActivityCompat.checkSelfPermission(getApplicationContext(), Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) {
return;
}
try {
cameraSource.start(holder);
} catch (IOException e) {
e.printStackTrace();
}
}
@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  qrCode = detections.getDetectedItems();
if (qrCode.size() != 0) {
qrCodeText.post(new Runnable() {
@Override
public void run() {
qrCodeText.setText(qrCode.valueAt(0).displayValue);
addInList(qrCode.valueAt(0).displayValue);
}
});
}
}
});
}
private void addInList(String scannResult) {
if (scannList.isEmpty()) {
scannList.add(scannResult);
} else {
String a = scannList.get(scannList.size() - 1);
if (!a.equals(scannResult)) {
scannList.add(scannResult);
}
}
for (String s : scannList) {
Log.e("s", "onCreate: " + s);
}
Log.e("size", "addInList: " + scannList.size());
}
@Override
protected void onDestroy() {
super.onDestroy();
}
}

5.布局页面：

<?xml version="1.0" encoding="utf-8"? 
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.example.administrator.testz.MainActivity" 
<SurfaceView
android:id="@+id/qrView"
android:layout_width="300dp"
android:layout_height="300dp"
android:layout_marginStart="32dp"
android:layout_marginLeft="32dp"
android:layout_marginEnd="32dp"
android:layout_marginRight="32dp"
android:orientation="vertical" / 
<TextView
android:id="@+id/tv"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:text="TextView"
android:textSize="30sp" / 
</RelativeLayout

以上就是本文的全部内容，希望对大家的学习有所帮助。