android商户扫码枪读取手机二维码

扫码抢实现读取二维码信息，本地扫码枪是外接写入设备，本质是监控读写输入，下面介绍下扫码设备读取支付二维码。

1.引入扫码设备辅助类

public class scangunkeyeventhelper {
 
    private final static long message_delay = 500;             //延迟500ms，判断扫码是否完成。
    private stringbuffer mstringbufferresult;                  //扫码内容
    private boolean mcaps;                                     //大小写区分
    private final handler mhandler;
    private final bluetoothadapter mbluetoothadapter;
    private final runnable mscanningfishedrunnable;
    private onscansuccesslistener monscansuccesslistener;
    private string mdevicename;
 
    public scangunkeyeventhelper(onscansuccesslistener onscansuccesslistener) {
        monscansuccesslistener = onscansuccesslistener ;
        mbluetoothadapter = bluetoothadapter.getdefaultadapter();
        mstringbufferresult = new stringbuffer();
        mhandler = new handler();
        mscanningfishedrunnable = new runnable() {
            @override
            public void run() {
                performscansuccess();
            }
        };
    }
 
 
    /**
     * 返回扫码成功后的结果
     */
    private void performscansuccess() {
        string barcode = mstringbufferresult.tostring();
        if (monscansuccesslistener != null)
            monscansuccesslistener.onscansuccess(barcode);
        mstringbufferresult.setlength(0);
    }
 
 
    /**
     * 扫码枪事件解析
     * @param event
     */
    public void analysiskeyevent(keyevent event) {
 
        int keycode = event.getkeycode();
 
        //字母大小写判断
        checkletterstatus(event);
 
        if (event.getaction() == keyevent.action_down) {
 
            char achar = getinputcode(event);;
 
            if (achar != 0) {
                mstringbufferresult.append(achar);
            }
 
            if (keycode == keyevent.keycode_enter) {
                //若为回车键，直接返回
                mhandler.removecallbacks(mscanningfishedrunnable);
                mhandler.post(mscanningfishedrunnable);
            } else {
                //延迟post，若500ms内，有其他事件
                mhandler.removecallbacks(mscanningfishedrunnable);
                mhandler.postdelayed(mscanningfishedrunnable, message_delay);
            }
 
        }
    }
    //检查shift键
    private void checkletterstatus(keyevent event) {
        int keycode = event.getkeycode();
        if (keycode == keyevent.keycode_shift_right || keycode == keyevent.keycode_shift_left) {
            if (event.getaction() == keyevent.action_down) {
                //按着shift键，表示大写
                mcaps = true;
            } else {
                //松开shift键，表示小写
                mcaps = false;
            }
        }
    }
 
    //获取扫描内容
    private char getinputcode(keyevent event) {
 
        int keycode = event.getkeycode();
 
        char achar;
 
        if (keycode >= keyevent.keycode_a && keycode <= keyevent.keycode_z) {
            //字母
            achar = (char) ((mcaps ? 'a' : 'a') + keycode - keyevent.keycode_a);
        } else if (keycode >= keyevent.keycode_0 && keycode <= keyevent.keycode_9) {
            //数字
            achar = (char) ('0' + keycode - keyevent.keycode_0);
        } else {
            //其他符号
            switch (keycode) {
                case keyevent.keycode_period:
                    achar = '.';
                    break;
                case keyevent.keycode_minus:
                    achar = mcaps ? '_' : '-';
                    break;
                case keyevent.keycode_slash:
                    achar = '/';
                    break;
                case keyevent.keycode_backslash:
                    achar = mcaps ? '|' : '\\';
                    break;
                default:
                    achar = 0;
                    break;
            }
        }
 
        return achar;
 
    }
 
    public interface onscansuccesslistener {
        void onscansuccess(string barcode);
    }
 
 
    public void ondestroy() {
        mhandler.removecallbacks(mscanningfishedrunnable);
        monscansuccesslistener = null;
    }
 
 
    //部分手机如三星，无法使用该方法
//    private void hasscangun() {
//        configuration cfg = getresources().getconfiguration();
//        return cfg.keyboard != configuration.keyboard_nokeys;
//    }
 
//    /**
//     * 扫描枪是否连接
//     * @return
//     */
//    public boolean hasscangun() {
//
//        if (mbluetoothadapter == null) {
//            return false;
//        }
//
//        set<bluetoothdevice> bluedevices = mbluetoothadapter.getbondeddevices();
//
//        if (bluedevices == null || bluedevices.size() <= 0) {
//            return false;
//        }
//
//        for (iterator<bluetoothdevice> iterator = bluedevices.iterator(); iterator.hasnext(); ) {
//            bluetoothdevice bluetoothdevice = iterator.next();
//
//            if (bluetoothdevice.getbluetoothclass().getmajordeviceclass() == bluetoothclass.device.major.peripheral) {
//                mdevicename = bluetoothdevice.getname();
//                return isinputdeviceexist(mdevicename);
//            }
//
//        }
//
//        return false;
//
//    }
 
    /**
     * 输入设备是否存在
     * @param devicename
     * @return
     */
    private boolean isinputdeviceexist(string devicename) {
        int[] deviceids = inputdevice.getdeviceids();
 
        for (int id : deviceids) {
            if (inputdevice.getdevice(id).getname().equals(devicename)) {
                return true;
            }
        }
        return false;
    }
 
    /**
     * 是否为扫码枪事件(部分机型keyevent获取的名字错误)
     * @param event
     * @return
     */
    @deprecated
    public boolean isscangunevent(keyevent event) {
        return event.getdevice().getname().equals(mdevicename);
    }
 
}

2. active里面实现代理方法

 //实现上述类接口‘
public class mainactivity extends appcompatactivity implements
        scangunkeyeventhelper.onscansuccesslistener
//重写扫码枪识别返回数据
@override
       public void onscansuccess(string barcode) {
 
        barcode = barcode;
        if (barcode != null && recordprice > 0 && paystring.equals
                ("readypay")) {
            paydishs();
        }
    }
 
//重写捕捉到扫码枪事件
    @override
    public boolean dispatchkeyevent(keyevent event) {
 
    mscangunkeyeventhelper.analysiskeyevent(event);
        return true;
    }

dispatchkeyevent里面分发事件一定设置 return true，否则扫码枪事件传递到屏幕其他按钮上

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。