public CaptureActivityHandler(
CaptureActivity activity,
Collection<BarcodeFormat> decodeFormats,
String characterSet,
CameraManager cameraManager) {
this.activity = activity;
// 启动扫描线程
decodeThread =
new DecodeThread(
activity,
decodeFormats,
characterSet,
new ViewfinderResultPointCallback(activity.getViewfinderView()));
decodeThread.start();
state = State.SUCCESS;
// Start ourselves capturing previews and decoding.
this.cameraManager = cameraManager;
// 开启相机预览界面
cameraManager.startPreview();
restartPreviewAndDecode();
}
/** 完成一次扫描后，只需要再调用此方法即可 */
private void restartPreviewAndDecode() {
if (state == State.SUCCESS) {
state = State.PREVIEW;
// 向decodeThread绑定的handler（DecodeHandler)发送解码消息
cameraManager.requestPreviewFrame(decodeThread.getHandler(), R.id.decode);
activity.drawViewfinder();
}
}
@SuppressWarnings("deprecation")
@Override
public void handleMessage(Message message) {
switch (message.what) {
case R.id.restart_preview: // 准备进行下一次扫描
Log.d(TAG, "Got restart preview message");
restartPreviewAndDecode();
break;
case R.id.decode_succeeded:
Log.d(TAG, "Got decode succeeded message");
state = State.SUCCESS;
Bundle bundle = message.getData();
Bitmap barcode = null;
float scaleFactor = 1.0f;
if (bundle != null) {
byte[] compressedBitmap = bundle.getByteArray(DecodeThread.BARCODE_BITMAP);
if (compressedBitmap != null) {
barcode =
BitmapFactory.decodeByteArray(compressedBitmap, 0, compressedBitmap.length, null);
// Mutable copy:
barcode = barcode.copy(Bitmap.Config.ARGB_8888, true);
}
scaleFactor = bundle.getFloat(DecodeThread.BARCODE_SCALED_FACTOR);
}
activity.handleDecode((Result) message.obj, barcode, scaleFactor);
break;
case R.id.decode_failed:
// We're decoding as fast as possible, so when one decode fails,
// start another.
state = State.PREVIEW;
cameraManager.requestPreviewFrame(decodeThread.getHandler(), R.id.decode);
break;
case R.id.return_scan_result:
Log.d(TAG, "Got return scan result message");
activity.setResult(Activity.RESULT_OK, (Intent) message.obj);
activity.finish();
break;
case R.id.launch_product_query:
Log.d(TAG, "Got product query message");
String url = (String) message.obj;
Intent intent = new Intent(Intent.ACTION_VIEW);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_WHEN_TASK_RESET);
intent.setData(Uri.parse(url));
/** 这段代码是zxing项目组想要用chrome打开浏览器浏览url */
ResolveInfo resolveInfo =
activity.getPackageManager().resolveActivity(intent, PackageManager.MATCH_DEFAULT_ONLY);
String browserPackageName = null;
if (resolveInfo != null && resolveInfo.activityInfo != null) {
browserPackageName = resolveInfo.activityInfo.packageName;
Log.d(TAG, "Using browser in package " + browserPackageName);
}
// Needed for default Android browser / Chrome only apparently
if ("com.android.browser".equals(browserPackageName)
|| "com.android.chrome".equals(browserPackageName)) {
intent.setPackage(browserPackageName);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
intent.putExtra(Browser.EXTRA_APPLICATION_ID, browserPackageName);
}
try {
activity.startActivity(intent);
} catch (ActivityNotFoundException ignored) {
Log.w(TAG, "Can't find anything to handle VIEW of URI " + url);
}
break;
}
}