MainActivity

package com.example.qrcode_demo06;

import android.Manifest;
import android.content.Context;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.graphics.Bitmap;
import android.os.AsyncTask;
import android.os.Build;
import android.support.annotation.NonNull;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.View;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.Toast;

import java.lang.ref.WeakReference;

import cn.bingoogolapple.qrcode.zxing.QRCodeEncoder;

public class MainActivity extends AppCompatActivity {

    private ImageView mImageView;
    private EditText mEditText;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        initView();
    }

    private void initView() {
        mImageView = findViewById(R.id.imageView);
        mEditText = findViewById(R.id.editText);
        findViewById(R.id.look).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Toast.makeText(MainActivity.this, "掃一掃",Toast.LENGTH_SHORT).show();
                checkPermission();
            }
        });

        findViewById(R.id.success).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                createQRcode();
            }
        });

    }
   //判斷許可權
    private void checkPermission(){
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M){
            if (ContextCompat.checkSelfPermission(this, Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) {
                ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.CAMERA},200);
            }else{
                startActivity(new Intent(MainActivity.this, ScanActivity.class));
            }
        }else {
            startActivity(new Intent(MainActivity.this, ScanActivity.class));
        }

    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        if (requestCode == 200 && grantResults[0] == PackageManager.PERMISSION_GRANTED){
            startActivity(new Intent(MainActivity.this, ScanActivity.class));
        }
    }

    //生成二維碼
    private void createQRcode() {
         QRTask qrTask = new QRTask(this, mImageView, mEditText);
         qrTask.execute(mEditText.getText().toString());
    }

    static class QRTask extends AsyncTask<String, Void, Bitmap>{
        private WeakReference<Context> mContext;
        private WeakReference<ImageView> mImageView;

        public QRTask(Context context, ImageView image, EditText ed) {
            mContext = new WeakReference<>(context);
            mImageView = new WeakReference<>(image);
        }

        @Override
        protected Bitmap doInBackground(String... params) {
            String str = params[0];
            if (TextUtils.isEmpty(str)) {
                return null;
            }
            int size = mContext.get().getResources().getDimensionPixelOffset(R.dimen.success_size);
            return QRCodeEncoder.syncEncodeQRCode(str, size);
        }

        @Override
        protected void onPostExecute(Bitmap bitmap) {
            super.onPostExecute(bitmap);
            if (bitmap != null) {
                mImageView.get().setImageBitmap(bitmap);
            } else {
                Toast.makeText(mContext.get(), "生成失敗", Toast.LENGTH_SHORT).show();
            }
        }

    }

}

 

ScanActivity

package com.example.qrcode_demo06;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;

import cn.bingoogolapple.qrcode.core.QRCodeView;
import cn.bingoogolapple.qrcode.zxing.ZXingView;

public class ScanActivity extends AppCompatActivity implements QRCodeView.Delegate {

    private ZXingView mZXingView;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_scan);
        mZXingView = findViewById(R.id.zxingView);
        mZXingView.setDelegate(this);
        findViewById(R.id.sao).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                mZXingView.changeToScanBarcodeStyle();
            }
        });
    }


    @Override
    protected void onResume() {
        super.onResume();
        mZXingView.startCamera();
        mZXingView.startSpotAndShowRect();
        mZXingView.openFlashlight();
    }

    @Override
    protected void onStop() {
        super.onStop();
        mZXingView.stopCamera();
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        mZXingView.onDestroy();
    }


    @Override
    public void onScanQRCodeSuccess(String result) {
        Log.i("dj", "result is " + result);
    }

    @Override
    public void onCameraAmbientBrightnessChanged(boolean isDark) {

    }

    @Override
    public void onScanQRCodeOpenCameraError() {

    }
}

 

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    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"
    android:orientation="vertical"
    tools:context=".MainActivity">

    <Button
        android:id="@+id/look"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="掃描二維碼"
        android:textSize="20sp"
        android:layout_marginTop="10dp"
        />

    <EditText
        android:id="@+id/editText"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="20dp"
        />
    <Button
        android:id="@+id/success"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="生成二維碼"
        android:textSize="20sp"
        />
    <ImageView
        android:id="@+id/imageView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:layout_marginTop="30dp"
        />

</LinearLayout>
 

activity_scan.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
    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=".ScanActivity">

    <cn.bingoogolapple.qrcode.zxing.ZXingView
        android:id="@+id/zxingView"
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>

    <TextView
        android:id="@+id/sao"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="掃一掃"
        android:textSize="30sp"
        android:textColor="#ffff"
        android:gravity="center"
        />

</android.support.constraint.ConstraintLayout>

依賴

implementation 'cn.bingoogolapple:bga-qrcode-zxing:1.3.4'

許可權

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