Android 开发中使用开源框架 DataDroid

DataDroid 框架简介

       DataDroid是基于Android平台的一个开源的开发库,基于Android 的RESTful封装用来简化Android应用中的数据管理.该开源库的下载地址为 CSDN资源.

DataDriod 在Android项目中的使用

      从github上clone下来的源代码中就有很多种类型的数据管理的demo,这里就简单得描述一下通过DataDroid的工作流程进行一个打开摄像头的过程.想看下面项目的源码的可以去我的github查看,地址:Github

     1.以单例模式建立一个请求管理器,这里需要注意的是在构造父类的时候,需要将一个RequestService传递给请求管理器,在调用RequestManager的execute方法时,会启动这个service.

<span style="font-family:Microsoft YaHei;font-size:14px;">public class CameraRequestManager extends RequestManager {
    // Singleton management
    private static CameraRequestManager sInstance;

    public synchronized static CameraRequestManager from(Context context) {
        if (sInstance == null) {
            sInstance = new CameraRequestManager(context);
        }

        return sInstance;
    }
	private CameraRequestManager(Context context) {
		super(context,CameraRequestService.class);
	}

}</span>

     2.创建一个请求工厂,来创建各种不同的请求,这里就提供了一个返回打开摄像头的请求.

<span style="font-family:Microsoft YaHei;font-size:14px;">public final class CameraRequestFactory {
	// Request types
	public static final int REQUEST_TYPE_OPEN_CAMERA = 0;
	
    // Response data
    public static final String BUNDLE_EXTRA_SWITCH = 
    		"cn.jesse.camera.datadroid.data.switch";
    public static final String BUNDLE_EXTRA_OPEN_CAMERA = 
    		"cn.jesse.camera.datadroid.data.opencamera";
    public static final String BUNDLE_EXTRA_RESULT =
            "com.foxykeep.datadroidpoc.extra.result";
    public static final String BUNDLE_EXTRA_ERROR_MESSAGE =
            "com.foxykeep.datadroidpoc.extra.errorMessage";
    
    
    public static Request getOpeningCameraOperation(int type){
    	Request request = new Request(REQUEST_TYPE_OPEN_CAMERA);
        request.setMemoryCacheEnabled(true);
        request.put(OpenCameraOperation.PARAM_METHOD, type);
        return request;
    }
}</span>

     3.创建一个打开摄像头的operation,打开摄像头这个动作的所有操作都在这个operation中完成,并且完成之后可以通过bundle来将打开的结果回调给调用的activity.

<span style="font-family:Microsoft YaHei;font-size:14px;">public class OpenCameraOperation implements Operation {
	private final String TAG = OpenCameraOperation.class.getSimpleName();
	public static final String PARAM_METHOD = "cn.jesse.camera.extra.cameraType";
	@Override
	public Bundle execute(Context context, Request request)
			throws ConnectionException, DataException, CustomRequestException {
		Log.i(TAG, "execute");
		int cameraType = request.getInt(PARAM_METHOD);
		Log.i(TAG, "execute, camera type" + cameraType);
		Bundle bundle = new Bundle();
        bundle.putInt(CameraRequestFactory.BUNDLE_EXTRA_SWITCH, CameraRequestFactory.REQUEST_TYPE_OPEN_CAMERA);
        bundle.putBoolean(CameraRequestFactory.BUNDLE_EXTRA_OPEN_CAMERA,true);
        return bundle;
	}
}</span>

     4.创建RequestService,根据不同的请求类型提供与之相对应的operation.

<span style="font-family:Microsoft YaHei;font-size:14px;">public class CameraRequestService extends RequestService {

	@Override
	public Operation getOperationForType(int requestType) {
		switch (requestType) {
		case CameraRequestFactory.REQUEST_TYPE_OPEN_CAMERA:
			return new OpenCameraOperation();
		}
		return null;
	}
	
    @Override
    protected Bundle onCustomRequestException(Request request, CustomRequestException exception) {
        if (exception instanceof MyCustomRequestException) {
            Bundle bundle = new Bundle();
            bundle.putString(CameraRequestFactory.BUNDLE_EXTRA_ERROR_MESSAGE,
                    "MyCustomRequestException thrown.");
            return bundle;
        }
        return super.onCustomRequestException(request, exception);
    }
}</span>

        5.建立datadroid的activity,提供对datadroid 请求和请求队列的管理.

<span style="font-family:Microsoft YaHei;font-size:14px;">public abstract class DataDroidActivity extends FragmentActivity {

    private static final String SAVED_STATE_REQUEST_LIST = "savedStateRequestList";

    protected CameraRequestManager mRequestManager;
    protected ArrayList<Request> mRequestList;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        mRequestManager = CameraRequestManager.from(this);

        if (savedInstanceState != null) {
            mRequestList = savedInstanceState.getParcelableArrayList(SAVED_STATE_REQUEST_LIST);
        } else {
            mRequestList = new ArrayList<Request>();
        }
    }

    @Override
    protected void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);

        outState.putParcelableArrayList(SAVED_STATE_REQUEST_LIST, mRequestList);
    }

    protected void showBadDataErrorDialog() {
        new ErrorDialogFragmentBuilder(this).setTitle(R.string.dialog_error_data_error_title)
                .setMessage(R.string.dialog_error_data_error_message).show();
    }
}</span>

        6.构建我们自己的activity继承自上面的DatadroidActivity, 在想要打开摄像头的时候,只需要从请求工厂中拿到openCamera的请求,用请求管理器来执行这个请求,并把该请求放入到请求队列中.....最后openCamera的结果就会通过onRequestFinished的回调来获取,整个过程还是比较简单的.

<span style="font-family:Microsoft YaHei;font-size:14px;">public class CameraActivity extends DataDroidActivity
							implements ActionBar.OnNavigationListener, RequestListener, 
										ConnectionErrorDialogListener{
	private String TAG = CameraActivity.class.getSimpleName();
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_camera);
		Log.i(TAG, "CameraActivity has been created");
		Request openCameraRequest = CameraRequestFactory.getOpeningCameraOperation(Definition.CameraType.Default);
        mRequestManager.execute(openCameraRequest, this);
        mRequestList.add(openCameraRequest);
	}

	@Override
	public void onRequestFinished(Request request, Bundle bundle) {
        if (mRequestList.contains(request)) {
            setProgressBarIndeterminateVisibility(false);
            mRequestList.remove(request);
            int choose = bundle.getInt(CameraRequestFactory.BUNDLE_EXTRA_SWITCH);
            switch(choose){
            case CameraRequestFactory.REQUEST_TYPE_OPEN_CAMERA:{
            	boolean openCameraStatus = false;
            	openCameraStatus = bundle.getBoolean(CameraRequestFactory.BUNDLE_EXTRA_OPEN_CAMERA);
            	if(openCameraStatus){
            		Log.i(TAG, "open camera succeed");
            	}else{
            	}
            	break;
            }
            }
        }
	}
}</span>