org.madmatrix.zxing.android.CaptureActivity.java Source code

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Here is the source code for org.madmatrix.zxing.android.CaptureActivity.java

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/*
 * Copyright (C) 2008 ZXing authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.madmatrix.zxing.android;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import java.util.Map;

import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.protocol.HTTP;
import org.apache.http.util.EntityUtils;
import org.madmatrix.zxing.android.camera.CameraManager;

import android.annotation.SuppressLint;
import android.app.Activity;
import android.app.AlertDialog;
import android.app.ProgressDialog;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.os.AsyncTask;
import android.os.Bundle;
import android.os.Handler;
import android.preference.PreferenceManager;
import android.util.Log;
import android.view.Gravity;
import android.view.KeyEvent;
import android.view.LayoutInflater;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.view.ViewGroup;
import android.view.Window;
import android.view.WindowManager;
import android.widget.TextView;
import android.widget.Toast;

import com.google.zxing.BarcodeFormat;
import com.google.zxing.DecodeHintType;
import com.google.zxing.Result;
import com.google.zxing.ResultPoint;

/**
 * This activity opens the camera and does the actual scanning on a background
 * thread. It draws a viewfinder to help the user place the barcode correctly,
 * shows feedback as the image processing is happening, and then overlays the
 * results when a scan is successful.
 * 
 * Activity? 1. camera????? 2.
 * ???viewfinder??? 3. ???????
 * 
 * @author dswitkin@google.com (Daniel Switkin)
 * @author Sean Owen
 */
public class CaptureActivity extends Activity implements SurfaceHolder.Callback {

    // ****************************************************************************
    private ProgressDialog pDialog;
    private final String URI_CLOCK_IN = "http://flash60905.qov.tw/test.php";
    public static final int REFRESH_DATA = 0x00000001;

    // ????
    @SuppressLint("HandlerLeak")
    Handler myHandler = new Handler() {
        public void handleMessage(android.os.Message msg) {
            switch (msg.what) {
            case REFRESH_DATA:
                String result = null;
                //msg.obj?String
                if (msg.obj instanceof String) {
                    result = (String) msg.obj;
                }
                if (result != null) {
                    // Internet
                    /*
                     * Toast.makeText(getApplicationContext(), result,
                     * Toast.LENGTH_SHORT).show();
                     */
                    //???
                    showMyToast(result);
                }
                break;
            }

        };
    };
    // ****************************************************************************

    //   private static final String TAG = CaptureActivity.class.getSimpleName();

    private static final long BULK_MODE_SCAN_DELAY_MS = 3000L;//???

    private CameraManager cameraManager;

    private CaptureActivityHandler handler;

    private ViewfinderView viewfinderView;

    /**
     * ????"????"??
     */
    private TextView statusView;

    /**
     * ????
     */
    private View resultView;

    private Result lastResult;

    private boolean hasSurface;

    private IntentSource source;

    /**
     * ??(MultiFormatReader?) ?????EAN-13QR
     * Code ?DecodeHintType.POSSIBLE_FORMATS
     * ?DecodeThreadhints.put(DecodeHintType.POSSIBLE_FORMATS,
     * decodeFormats);
     */
    private Collection<BarcodeFormat> decodeFormats;

    /**
     * ??(MultiFormatReader?) ??
     * ?DecodeHintType.CHARACTER_SET
     * ?DecodeThreadhints.put(DecodeHintType.CHARACTER_SET,
     * characterSet);
     */
    private String characterSet;

    /**
     * ??(MultiFormatReader?) ?MultiFormatReader
     * ?decodeFormatscharacterSetdecodeHints MultiFormatReader
     * ?DecodeHandlermultiFormatReader.setHints(hints);
     */
    private Map<DecodeHintType, ?> decodeHints;

    /**
     * ????activity
     * ???CaptureActivity?.???????
     */
    private InactivityTimer inactivityTimer;

    ViewfinderView getViewfinderView() {
        return viewfinderView;
    }

    public Handler getHandler() {
        return handler;
    }

    CameraManager getCameraManager() {
        return cameraManager;
    }

    @Override
    public void onCreate(Bundle icicle) {
        super.onCreate(icicle);

        // ?????
        Window window = getWindow();
        window.addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
        setContentView(R.layout.capture);

        // ????onResume
        hasSurface = false;
        inactivityTimer = new InactivityTimer(this);

        PreferenceManager.setDefaultValues(this, R.xml.preferences, false);
    }

    @Override
    protected void onResume() {
        super.onResume();

        // CameraManager must be initialized here, not in onCreate(). This is
        // necessary because we don't
        // want to open the camera driver and measure the screen size if we're
        // going to show the help on
        // first launch. That led to bugs where the scanning rectangle was the
        // wrong size and partially
        // off screen.
        /**
         * ?????????
         * ?onCreateonCreate????bug
         */
        cameraManager = new CameraManager(getApplication());

        viewfinderView = (ViewfinderView) findViewById(R.id.viewfinder_view);
        viewfinderView.setCameraManager(cameraManager);
        resultView = findViewById(R.id.result_view);
        statusView = (TextView) findViewById(R.id.status_view);

        handler = null;
        lastResult = null;

        // ???????
        resetStatusView();

        // ???SurfaceView???
        // ?SurfaceView??:http://blog.csdn.net/luoshengyang/article/details/8661317
        SurfaceView surfaceView = (SurfaceView) findViewById(R.id.preview_view);
        SurfaceHolder surfaceHolder = surfaceView.getHolder();
        if (hasSurface) {
            // The activity was paused but not stopped, so the surface still
            // exists. Therefore
            // surfaceCreated() won't be called, so init the camera here.
            initCamera(surfaceHolder);
        } else {
            // Install the callback and wait for surfaceCreated() to init the
            // camera.
            // SurfaceViewsurfaceCreatedsurfaceCreatedinitCamera()
            surfaceHolder.addCallback(this);
        }

        // ?
        inactivityTimer.onResume();

        source = IntentSource.NONE;
        decodeFormats = null;
        characterSet = null;
    }

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

        // ?
        inactivityTimer.onPause();

        // ??
        cameraManager.closeDriver();
        if (!hasSurface) {
            SurfaceView surfaceView = (SurfaceView) findViewById(R.id.preview_view);
            SurfaceHolder surfaceHolder = surfaceView.getHolder();
            surfaceHolder.removeCallback(this);
        }
        super.onPause();
    }

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

    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {
        switch (keyCode) {
        case KeyEvent.KEYCODE_BACK: // ?
            if ((source == IntentSource.NONE) && lastResult != null) {
                restartPreviewAfterDelay(0L);
                return true;
            }
            break;
        case KeyEvent.KEYCODE_FOCUS:
        case KeyEvent.KEYCODE_CAMERA:
            // Handle these events so they don't launch the Camera app
            return true;
        // Use volume up/down to turn on light
        case KeyEvent.KEYCODE_VOLUME_DOWN:
            cameraManager.setTorch(false);
            return true;
        case KeyEvent.KEYCODE_VOLUME_UP:
            cameraManager.setTorch(true);
            return true;
        }
        return super.onKeyDown(keyCode, event);
    }

    @Override
    public void surfaceCreated(SurfaceHolder holder) {
        /*if (holder == null) {
           Log.e(TAG,
           "*** WARNING *** surfaceCreated() gave us a null surface!");
        }*/
        if (!hasSurface) {
            hasSurface = true;
            initCamera(holder);
        }
    }

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

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

    }

    /**
     * A valid barcode has been found, so give an indication of success and show
     * the results.
     * 
     * @param rawResult
     *            The contents of the barcode.
     * @param scaleFactor
     *            amount by which thumbnail was scaled
     * @param barcode
     *            A greyscale bitmap of the camera data which was decoded.
     */
    public void handleDecode(Result rawResult, Bitmap barcode, float scaleFactor) {
        inactivityTimer.onActivity();
        lastResult = rawResult;

        boolean fromLiveScan = barcode != null;
        if (fromLiveScan) {
            // Then not from history, so beep/vibrate and we have an image to
            // draw on
            drawResultPoints(barcode, scaleFactor, rawResult);
        }

        switch (source) {
        case NONE:

            // ?"????"???????
            /*
             * Toast.makeText( getApplicationContext(), "???!",
             * Toast.LENGTH_SHORT).show();
             */
            showMyToast("???...");

            String resToSql = rawResult.getText();
            new SendPostToInternet().execute(resToSql);

            /*
             * Message msg = new Message(); Bundle myBundle = msg.getData();
             * resEcho = myBundle.getString("echo"); showMyToast(resEcho);
             */
            // Wait a moment or else it will scan the same barcode
            // continuously about 3 times
            restartPreviewAfterDelay(BULK_MODE_SCAN_DELAY_MS);
            break;
        }
    }

    /**
     * Superimpose a line for 1D or dots for 2D to highlight the key features of
     * the barcode.
     * 
     * @param barcode
     *            A bitmap of the captured image.
     * @param scaleFactor
     *            amount by which thumbnail was scaled
     * @param rawResult
     *            The decoded results which contains the points to draw.
     */
    private void drawResultPoints(Bitmap barcode, float scaleFactor, Result rawResult) {
        ResultPoint[] points = rawResult.getResultPoints();
        if (points != null && points.length > 0) {
            Canvas canvas = new Canvas(barcode);
            Paint paint = new Paint();
            paint.setColor(getResources().getColor(R.color.result_points));
            if (points.length == 2) {
                paint.setStrokeWidth(4.0f);
                drawLine(canvas, paint, points[0], points[1], scaleFactor);
            } else if (points.length == 4 && (rawResult.getBarcodeFormat() == BarcodeFormat.UPC_A
                    || rawResult.getBarcodeFormat() == BarcodeFormat.EAN_13)) {
                // Hacky special case -- draw two lines, for the barcode and
                // metadata
                drawLine(canvas, paint, points[0], points[1], scaleFactor);
                drawLine(canvas, paint, points[2], points[3], scaleFactor);
            } else {
                paint.setStrokeWidth(10.0f);
                for (ResultPoint point : points) {
                    if (point != null) {
                        canvas.drawPoint(scaleFactor * point.getX(), scaleFactor * point.getY(), paint);
                    }
                }
            }
        }
    }

    private static void drawLine(Canvas canvas, Paint paint, ResultPoint a, ResultPoint b, float scaleFactor) {
        if (a != null && b != null) {
            canvas.drawLine(scaleFactor * a.getX(), scaleFactor * a.getY(), scaleFactor * b.getX(),
                    scaleFactor * b.getY(), paint);
        }
    }

    private void initCamera(SurfaceHolder surfaceHolder) {
        if (surfaceHolder == null) {
            throw new IllegalStateException("No SurfaceHolder provided");
        }
        if (cameraManager.isOpen()) {
            //         Log.w(TAG,
            //               "initCamera() while already open -- late SurfaceView callback?");
            return;
        }
        try {
            cameraManager.openDriver(surfaceHolder);
            // Creating the handler starts the preview, which can also throw a
            // RuntimeException.
            if (handler == null) {
                handler = new CaptureActivityHandler(this, decodeFormats, decodeHints, characterSet, cameraManager);
            }

        } catch (IOException ioe) {
            //         Log.w(TAG, ioe);
            displayFrameworkBugMessageAndExit();
        } catch (RuntimeException e) {
            // Barcode Scanner has seen crashes in the wild of this variety:
            // java.?lang.?RuntimeException: Fail to connect to camera service
            //         Log.w(TAG, "Unexpected error initializing camera", e);
            displayFrameworkBugMessageAndExit();
        }
    }

    private void displayFrameworkBugMessageAndExit() {
        AlertDialog.Builder builder = new AlertDialog.Builder(this);
        builder.setTitle(getString(R.string.app_name));
        builder.setMessage(getString(R.string.msg_camera_framework_bug));
        builder.setPositiveButton(R.string.button_ok, new FinishListener(this));
        builder.setOnCancelListener(new FinishListener(this));
        builder.show();
    }

    /**
     * ????? ???????
     * 
     * @param delayMS
     */
    public void restartPreviewAfterDelay(long delayMS) {
        if (handler != null) {
            handler.sendEmptyMessageDelayed(R.id.restart_preview, delayMS);
        }
        resetStatusView();
    }

    /**
     * ?????
     */
    private void resetStatusView() {
        resultView.setVisibility(View.GONE);
        statusView.setText(R.string.msg_default_status);
        statusView.setVisibility(View.VISIBLE);
        viewfinderView.setVisibility(View.VISIBLE);
        lastResult = null;
    }

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

    // toast
    public void showMyToast(String content) {
        LayoutInflater inflater = getLayoutInflater();
        View layout = inflater.inflate(R.layout.toast_layout, (ViewGroup) findViewById(R.id.toast_layout));

        TextView toast_content = (TextView) layout.findViewById(R.id.toast_content);

        toast_content.setText(content);

        Toast toast = new Toast(getApplicationContext());
        toast.setGravity(Gravity.CENTER_VERTICAL, 0, 0);
        toast.setDuration(Toast.LENGTH_SHORT);
        toast.setView(layout);
        toast.show();
    }

    class SendPostToInternet extends AsyncTask<String, Void, String> {
        private String result;

        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            pDialog = new ProgressDialog(CaptureActivity.this);
            pDialog.setMessage("Clock In ..");
            pDialog.setIndeterminate(false);
            pDialog.setCancelable(true);
            pDialog.show();
        }

        @Override
        protected String doInBackground(String... arg0) {

            HttpPost httpRequest = new HttpPost(URI_CLOCK_IN);

            List<NameValuePair> params = new ArrayList<NameValuePair>();

            params.add(new BasicNameValuePair("var_phone", arg0[0]));

            try {
                httpRequest.setEntity(new UrlEncodedFormEntity(params, HTTP.UTF_8));
                HttpResponse httpResponse = new DefaultHttpClient().execute(httpRequest);
                if (httpResponse.getStatusLine().getStatusCode() == 200) {

                    String webResult = EntityUtils.toString(httpResponse.getEntity());

                    return result = webResult;
                }
            } catch (Exception e) {
                result = "??";
            }
            return null;
        }

        @Override
        protected void onPostExecute(String file_url) {
            // dismiss the dialog once done
            pDialog.dismiss();
            Toast.makeText(getApplicationContext(), result, Toast.LENGTH_LONG).show();
        }

    }
}