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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 ai.pai.lensman.qrcode;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import com.google.zxing.Result;
import ai.pai.lensman.R;
/**
* This class handles all the messaging which comprises the state machine for
* capture.
*
* @author dswitkin@google.com (Daniel Switkin)
*/
public class CaptureActivityHandler extends Handler {
private final QRCaptureActivity activity;
private final DecodeThread decodeThread;
private final CameraManager cameraManager;
private State state;
private enum State {
PREVIEW, SUCCESS, DONE
}
public CaptureActivityHandler(QRCaptureActivity activity, CameraManager cameraManager, int decodeMode) {
this.activity = activity;
decodeThread = new DecodeThread(activity, decodeMode);
decodeThread.start();
state = State.SUCCESS;
// Start ourselves capturing previews and decoding.
this.cameraManager = cameraManager;
cameraManager.startPreview();
restartPreviewAndDecode();
}
@Override
public void handleMessage(Message message) {
if (message.what == R.id.restart_preview) {
restartPreviewAndDecode();
} else if (message.what == R.id.decode_succeeded) {
state = State.SUCCESS;
Bundle bundle = message.getData();
activity.handleDecode((Result) message.obj, bundle);
} else if (message.what == 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);
} else if (message.what == R.id.return_scan_result) {
activity.setResult(Activity.RESULT_OK, (Intent) message.obj);
activity.finish();
}
}
public void quitSynchronously() {
state = State.DONE;
cameraManager.stopPreview();
Message quit = Message.obtain(decodeThread.getHandler(), R.id.quit);
quit.sendToTarget();
try {
// Wait at most half a second; should be enough time, and onPause()
// will timeout quickly
decodeThread.join(500L);
} catch (InterruptedException e) {
// continue
}
// Be absolutely sure we don't send any queued up messages
removeMessages(R.id.decode_succeeded);
removeMessages(R.id.decode_failed);
}
private void restartPreviewAndDecode() {
if (state == State.SUCCESS) {
state = State.PREVIEW;
cameraManager.requestPreviewFrame(decodeThread.getHandler(), R.id.decode);
}
}
}
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