CaptureHandler.java

package com.zbar.lib.decode;

import android.os.Handler;
import android.os.Message;

import com.zbar.lib.CaptureView;
import com.zbar.lib.R;
import com.zbar.lib.camera.CameraManager;

/**
 * 作者: 陈涛(1076559197@qq.com)
 * 
 * 时间: 2014年5月9日 下午12:23:32
 *
 * 版本: V_1.0.0
 *
 * 描述: 扫描消息转发
 */
public final class CaptureHandler extends Handler {

	DecodeThread decodeThread;
	CaptureView captureView;
	private State state;

	private enum State {
		PREVIEW, SUCCESS, DONE
	}

	public CaptureHandler(CaptureView captureView) {
		this.captureView = captureView;
		decodeThread = new DecodeThread(captureView);
		decodeThread.start();
		state = State.SUCCESS;
		CameraManager.get().startPreview();
		restartPreviewAndDecode();
	}

	@Override
	public void handleMessage(Message message) {
        final int id = message.what;
        if (id == R.id.auto_focus){
            if (state == State.PREVIEW) {
                CameraManager.get().requestAutoFocus(this, R.id.auto_focus);
            }
        } else if (id==R.id.restart_preview){
            restartPreviewAndDecode();
        } else if (id == R.id.decode_succeeded){
            state = State.SUCCESS;
            captureView.handleDecode((String) message.obj);// 解析成功，回调
        } else if (id == R.id.decode_failed){
            state = State.PREVIEW;
            CameraManager.get().requestPreviewFrame(decodeThread.getHandler(),
                    R.id.decode);
        }

	}

	public void quitSynchronously() {
		state = State.DONE;
		CameraManager.get().stopPreview();
		removeMessages(R.id.decode_succeeded);
		removeMessages(R.id.decode_failed);
		removeMessages(R.id.decode);
		removeMessages(R.id.auto_focus);
	}

	private void restartPreviewAndDecode() {
		if (state == State.SUCCESS) {
			state = State.PREVIEW;
			CameraManager.get().requestPreviewFrame(decodeThread.getHandler(),
					R.id.decode);
			CameraManager.get().requestAutoFocus(this, R.id.auto_focus);
		}
	}

}