正文 

　　上文，我们讲了 二维码生成 解码

　　这次我们就用 android 来扫一下，实现android 扫二维码。

　　　　下载扫一扫

包结构-介绍

　　#com.zxing.xx 　　这是 zxing 库提供的

　　#BarCodeActivity 

实战

　　一个按钮，一个显示结果的界面

package sedion.jeffli.activity;

import sedion.jeffli.itp.R;

import com.zxing.activity.CaptureActivity;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;

public class BarCodeActivity extends Activity
{

    private TextView resultTextView;            //返回显示结果（以后没有用的）
    private Button   scanBarCodeButton;

    @Override
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.barcode);

        resultTextView = (TextView) this.findViewById(R.id.tv_scan_result);
        scanBarCodeButton = (Button) this.findViewById(R.id.btn_scan_barcode);

        scanBarCodeButton.setOnClickListener(new OnClickListener()
        {
            @Override
            public void onClick(View v)
            {
                //打开扫描界面
                Intent openCameraIntent = new Intent(BarCodeActivity.this,CaptureActivity.class);
                startActivityForResult(openCameraIntent, 0);
            }
        });
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data)
    {
        super.onActivityResult(requestCode, resultCode, data);
        //判断处理结果，并显示
        if (resultCode == RESULT_OK)
        {
            Bundle bundle = data.getExtras();
            String scanResult = bundle.getString("result");
            //Toast.makeText(this, "result", Toast.LENGTH_LONG).show();
            resultTextView.setText(scanResult);
        }
    }
}

 　　#new Intent(BarCodeActivity.this,CaptureActivity.class);

　　 　　打开扫描界面 -> CaptureActivity (这个是进行扫描的activity）

　　 #resultCode == RESULT_OK

　　　　判断是否成功，成功显示结果。

你会看到：

下面是扫描的界面：

　　CaptureActivity（zxing库提供，nice）

package com.zxing.activity;

import java.io.IOException;
import java.util.Vector;

import sedion.jeffli.itp.R;
import android.app.Activity;
import android.content.Intent;
import android.content.res.AssetFileDescriptor;
import android.graphics.Bitmap;
import android.media.AudioManager;
import android.media.MediaPlayer;
import android.media.MediaPlayer.OnCompletionListener;
import android.os.Bundle;
import android.os.Handler;
import android.os.Vibrator;
import android.view.SurfaceHolder;
import android.view.SurfaceHolder.Callback;
import android.view.SurfaceView;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.Toast;

import com.google.zxing.BarcodeFormat;
import com.google.zxing.Result;
import com.zxing.camera.CameraManager;
import com.zxing.decoding.CaptureActivityHandler;
import com.zxing.decoding.InactivityTimer;
import com.zxing.view.ViewfinderView;
/**
 * Initial the camera
 * @author Ryan.Tang
 */
public class CaptureActivity extends Activity implements Callback {

    private CaptureActivityHandler handler;
    private ViewfinderView viewfinderView;
    private boolean hasSurface;
    private Vector<BarcodeFormat> decodeFormats;
    private String characterSet;
    private InactivityTimer inactivityTimer;
    private MediaPlayer mediaPlayer;
    private boolean playBeep;
    private static final float BEEP_VOLUME = 0.10f;
    private boolean vibrate;
    private Button cancelScanButton;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.camera);
        //ViewUtil.addTopView(getApplicationContext(), this, R.string.scan_card);
        CameraManager.init(getApplication());
        viewfinderView = (ViewfinderView) findViewById(R.id.viewfinder_view);
        cancelScanButton = (Button) this.findViewById(R.id.btn_cancel_scan);
        hasSurface = false;
        inactivityTimer = new InactivityTimer(this);
    }

    @Override
    protected void onResume() {
        super.onResume();
        SurfaceView surfaceView = (SurfaceView) findViewById(R.id.preview_view);
        SurfaceHolder surfaceHolder = surfaceView.getHolder();
        if (hasSurface) {
            initCamera(surfaceHolder);
        } else {
            surfaceHolder.addCallback(this);
            surfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
        }
        decodeFormats = null;
        characterSet = null;

        playBeep = true;
        AudioManager audioService = (AudioManager) getSystemService(AUDIO_SERVICE);
        if (audioService.getRingerMode() != AudioManager.RINGER_MODE_NORMAL) {
            playBeep = false;
        }
        initBeepSound();
        vibrate = true;

        //quit the scan view
        cancelScanButton.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                CaptureActivity.this.finish();
            }
        });
    }

    @Override
    protected void onPause() {
        super.onPause();
        if (handler != null) {
            handler.quitSynchronously();
            handler = null;
        }
        CameraManager.get().closeDriver();
    }

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

    /**
     * Handler scan result
     * @param result
     * @param barcode
     */
    public void handleDecode(Result result, Bitmap barcode) {
        inactivityTimer.onActivity();
        playBeepSoundAndVibrate();
        String resultString = result.getText();
        //FIXME
        if (resultString.equals("")) {
            Toast.makeText(CaptureActivity.this, "Scan failed!", Toast.LENGTH_SHORT).show();
        }else {
//            System.out.println("Result:"+resultString);
            Intent resultIntent = new Intent();
            Bundle bundle = new Bundle();
            bundle.putString("result", resultString);
            resultIntent.putExtras(bundle);
            this.setResult(RESULT_OK, resultIntent);
        }
        CaptureActivity.this.finish();
    }

    private void initCamera(SurfaceHolder surfaceHolder) {
        try {
            CameraManager.get().openDriver(surfaceHolder);
        } catch (IOException ioe) {
            return;
        } catch (RuntimeException e) {
            return;
        }
        if (handler == null) {
            handler = new CaptureActivityHandler(this, decodeFormats,
                    characterSet);
        }
    }

    @Override
    public void surfaceChanged(SurfaceHolder holder, int format, int width,
            int height) {

    }

    @Override
    public void surfaceCreated(SurfaceHolder holder) {
        if (!hasSurface) {
            hasSurface = true;
            initCamera(holder);
        }

    }

    @Override
    public void surfaceDestroyed(SurfaceHolder holder) {
        hasSurface = false;

    }

    public ViewfinderView getViewfinderView() {
        return viewfinderView;
    }

    public Handler getHandler() {
        return handler;
    }

    public void drawViewfinder() {
        viewfinderView.drawViewfinder();

    }

    private void initBeepSound() {
        if (playBeep && mediaPlayer == null) {
            // The volume on STREAM_SYSTEM is not adjustable, and users found it
            // too loud,
            // so we now play on the music stream.
            setVolumeControlStream(AudioManager.STREAM_MUSIC);
            mediaPlayer = new MediaPlayer();
            mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
            mediaPlayer.setOnCompletionListener(beepListener);

            AssetFileDescriptor file = getResources().openRawResourceFd(
                    R.raw.beep);
            try {
                mediaPlayer.setDataSource(file.getFileDescriptor(),
                        file.getStartOffset(), file.getLength());
                file.close();
                mediaPlayer.setVolume(BEEP_VOLUME, BEEP_VOLUME);
                mediaPlayer.prepare();
            } catch (IOException e) {
                mediaPlayer = null;
            }
        }
    }

    private static final long VIBRATE_DURATION = 200L;

    private void playBeepSoundAndVibrate() {
        if (playBeep && mediaPlayer != null) {
            mediaPlayer.start();
        }
        if (vibrate) {
            Vibrator vibrator = (Vibrator) getSystemService(VIBRATOR_SERVICE);
            vibrator.vibrate(VIBRATE_DURATION);
        }
    }

    /**
     * When the beep has finished playing, rewind to queue up another one.
     */
    private final OnCompletionListener beepListener = new OnCompletionListener() {
        public void onCompletion(MediaPlayer mediaPlayer) {
            mediaPlayer.seekTo(0);
        }
    };

}

你会看到：

总结

　　android 二维码扫描