public static boolean createQRImage(String content, int widthPix, int heightPix, Bitmap logoBm, String filePath) {
    try {
      if (content == null || "".equals(content)) {
        return false;
      }

      //配置参数
      Map<EncodeHintType, Object> hints = new HashMap<>();
      hints.put(EncodeHintType.CHARACTER_SET, "utf-8");
      //容错级别
      hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);
      //设置空白边距的宽度
      hints.put(EncodeHintType.MARGIN, 2); //default is 4

      // 图像数据转换，使用了矩阵转换
      BitMatrix bitMatrix = new QRCodeWriter().encode(content, BarcodeFormat.QR_CODE, widthPix, heightPix, hints);
      int[] pixels = new int[widthPix * heightPix];
      // 下面这里按照二维码的算法，逐个生成二维码的图片，
      // 两个for循环是图片横列扫描的结果
      for (int y = 0; y < heightPix; y++) {
        for (int x = 0; x < widthPix; x++) {
          if (bitMatrix.get(x, y)) {
            pixels[y * widthPix + x] = 0xff000000;
          } else {
            pixels[y * widthPix + x] = 0xffffffff;
          }
        }
      }

      // 生成二维码图片的格式，使用ARGB_8888
      Bitmap bitmap = Bitmap.createBitmap(widthPix, heightPix, Bitmap.Config.ARGB_8888);
      bitmap.setPixels(pixels, 0, widthPix, 0, 0, widthPix, heightPix);

      if (logoBm != null) {
        bitmap = addLogo(bitmap, logoBm);
      }

      //必须使用compress方法将bitmap保存到文件中再进行读取。直接返回的bitmap是没有任何压缩的，内存消耗巨大！
      return bitmap != null && bitmap.compress(Bitmap.CompressFormat.JPEG, 100, new FileOutputStream(filePath));
    } catch (WriterException | IOException e) {
      e.printStackTrace();
    }

    return false;
  }

private static Bitmap addLogo(Bitmap src, Bitmap logo) {
    if (src == null) {
      return null;
    }

    if (logo == null) {
      return src;
    }

    //获取图片的宽高
    int srcWidth = src.getWidth();
    int srcHeight = src.getHeight();
    int logoWidth = logo.getWidth();
    int logoHeight = logo.getHeight();

    if (srcWidth == 0 || srcHeight == 0) {
      return null;
    }

    if (logoWidth == 0 || logoHeight == 0) {
      return src;
    }

    //logo大小为二维码整体大小的1/5
    float scaleFactor = srcWidth * 1.0f / 5 / logoWidth;
    Bitmap bitmap = Bitmap.createBitmap(srcWidth, srcHeight, Bitmap.Config.ARGB_8888);
    try {
      Canvas canvas = new Canvas(bitmap);
      canvas.drawBitmap(src, 0, 0, null);
      canvas.scale(scaleFactor, scaleFactor, srcWidth / 2, srcHeight / 2);
      canvas.drawBitmap(logo, (srcWidth - logoWidth) / 2, (srcHeight - logoHeight) / 2, null);

      canvas.save(Canvas.ALL_SAVE_FLAG);
      canvas.restore();
    } catch (Exception e) {
      bitmap = null;
      e.getStackTrace();
    }

    return bitmap;
  }

private static String getFileRoot(Context context) {
    if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) {
      File external = context.getExternalFilesDir(null);
      if (external != null) {
        return external.getAbsolutePath();
      }
    }

    return context.getFilesDir().getAbsolutePath();
  }

public class SPUtil {

  private static final String CONFIG = "config";

  /**
   * 获取SharedPreferences实例对象
   *
   * @param fileName
   */
  private static SharedPreferences getSharedPreference(String fileName) {
    return QRCodeApplication.getInstance().getSharedPreferences(fileName, Context.MODE_PRIVATE);
  }

  /**
   * 保存一个String类型的值！
   */
  public static void putString(String key, String value) {
    SharedPreferences.Editor editor = getSharedPreference(CONFIG).edit();
    editor.putString(key, value).apply();
  }

  /**
   * 获取String的value
   */
  public static String getString(String key, String defValue) {
    SharedPreferences sharedPreference = getSharedPreference(CONFIG);
    return sharedPreference.getString(key, defValue);
  }

}

public static void showThreadImage(final Activity mContext, final String text, final ImageView imageView, final int centerPhoto) {
    String preContent = SPUtil.getString("share_code_content", "");
    if (text.equals(preContent)) {
      String preFilePath = SPUtil.getString("share_code_filePath", "");
      imageView.setImageBitmap(BitmapFactory.decodeFile(preFilePath));

    } else {
      SPUtil.putString("share_code_content", text);
      final String filePath = getFileRoot(mContext) + File.separator + "qr_" + System.currentTimeMillis() + ".jpg";
      SPUtil.putString("share_code_filePath", filePath);

      //二维码图片较大时，生成图片、保存文件的时间可能较长，因此放在新线程中
      new Thread(new Runnable() {
        @Override
        public void run() {
          boolean success = QRCodeUtil.createQRImage(text, 800, 800, BitmapFactory.decodeResource(mContext.getResources(), centerPhoto),
              filePath);

          if (success) {
            mContext.runOnUiThread(new Runnable() {
              @Override
              public void run() {
                imageView.setImageBitmap(BitmapFactory.decodeFile(filePath));
              }
            });
          }
        }
      }).start();
    }
  }

public class ContentActivity extends AppCompatActivity implements View.OnClickListener {

  private EditText etUrl;

  private Button btnConvert;

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_content);

    initView();
  }

  private void initView() {
    etUrl = (EditText) findViewById(R.id.et_url);
    btnConvert = (Button) findViewById(R.id.btn_convert);

    btnConvert.setOnClickListener(this);

  }

  @Override
  public void onClick(View v) {
    switch (v.getId()) {
      case R.id.btn_convert:
        String str_url = "https://" + etUrl.getText().toString();
        Bundle bundle = new Bundle();
        bundle.putString("url", str_url);
        // 当输入框为空时，提示用户
        if (str_url.equals("https://")) {
          Toast.makeText(getApplicationContext(), "输入框不能为空", Toast.LENGTH_SHORT).show();
        } else {
          Intent intent = new Intent(ContentActivity.this, MainActivity.class);
          intent.putExtras(bundle);
          startActivity(intent);
        }
        break;
      default:
        break;
    }
  }
}

public class MainActivity extends AppCompatActivity {

  private ImageView iv;

//  private String url = "http://weibo.com/cnwutianhao";

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    String str_url = getIntent().getExtras().getString("url");

    iv = (ImageView) findViewById(R.id.iv_qrcode);

    QRCodeUtil.showThreadImage(this, str_url, iv, R.mipmap.ic_launcher);
  }
}

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  android:orientation="vertical"
  android:padding="10dp">

  <EditText
    android:id="@+id/et_url"
    android:layout_width="match_parent"
    android:layout_height="50dp"
    android:layout_marginTop="100dp"
    android:hint="请输入网址"
    android:inputType="textUri" />

  <Button
    android:id="@+id/btn_convert"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentBottom="true"
    android:layout_centerHorizontal="true"
    android:layout_marginBottom="20dp"
    android:text="转换成二维码" />

</RelativeLayout>

<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"
  tools:context="com.tnnowu.android.qrcode.MainActivity">

  <ImageView
    android:id="@+id/iv_qrcode"
    android:layout_width="220dp"
    android:layout_height="220dp"
    android:layout_centerInParent="true"
    android:layout_marginTop="40dp"
    android:background="#FFFFFF" />

</RelativeLayout>