Java tutorial
/* * 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(); } } }