Android Open Source - esr-scanner Auto Focus Manager

• Back to App/code  ↑

From Project

Back to project page esr-scanner.

License

The source code is released under:

Apache License

Java Source Code

/*
 * Copyright (C) 2012 ZXing authors//ww  w.j ava 2 s.  com
 *
 * 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 ch.luklanis.esscan.camera;

import android.content.Context;
import android.content.SharedPreferences;
import android.hardware.Camera;
import android.os.AsyncTask;
import android.preference.PreferenceManager;
import android.util.Log;

import java.util.ArrayList;
import java.util.Collection;

import ch.luklanis.android.common.executor.AsyncTaskExecInterface;
import ch.luklanis.android.common.executor.AsyncTaskExecManager;
import ch.luklanis.esscan.PreferencesActivity;

final class AutoFocusManager implements Camera.AutoFocusCallback {

    private static final String TAG = AutoFocusManager.class.getSimpleName();

    private static final Collection<String> FOCUS_MODES_CALLING_AF;

    static {
        FOCUS_MODES_CALLING_AF = new ArrayList<String>(2);
        FOCUS_MODES_CALLING_AF.add(Camera.Parameters.FOCUS_MODE_AUTO);
        FOCUS_MODES_CALLING_AF.add(Camera.Parameters.FOCUS_MODE_MACRO);
    }

    private boolean active;
    private final boolean useAutoFocus;
    private final Camera camera;
    private AutoFocusTask outstandingTask;
    private final AsyncTaskExecInterface taskExec;

    AutoFocusManager(Context context, Camera camera) {
        this.camera = camera;
        taskExec = new AsyncTaskExecManager().build();
        SharedPreferences sharedPrefs = PreferenceManager.getDefaultSharedPreferences(context);
        String currentFocusMode = camera.getParameters().getFocusMode();
        useAutoFocus = !sharedPrefs.getBoolean(PreferencesActivity.KEY_ONLY_MACRO_FOCUS,
                false) && FOCUS_MODES_CALLING_AF.contains(currentFocusMode);
        Log.i(TAG,
                "Current focus mode '" + currentFocusMode + "'; use auto focus? " + useAutoFocus);
        //start();
    }

    @Override
    public synchronized void onAutoFocus(boolean success, Camera theCamera) {
        if (active && !success) {
            outstandingTask = new AutoFocusTask();
            taskExec.execute(outstandingTask);
        }
    }

    public synchronized void start() {
        //if (useAutoFocus) {
        active = true;
        try {
            camera.autoFocus(this);
        } catch (RuntimeException re) {
            // Have heard RuntimeException reported in Android 4.0.x+; continue?
            Log.w(TAG, "Unexpected exception while focusing", re);
        }
        //}
    }

    synchronized void stop() {
        //if (useAutoFocus) {
        try {
            camera.cancelAutoFocus();
        } catch (RuntimeException re) {
            // Have heard RuntimeException reported in Android 4.0.x+; continue?
            Log.w(TAG, "Unexpected exception while cancelling focusing", re);
        }
        //}
        if (outstandingTask != null) {
            outstandingTask.cancel(true);
            outstandingTask = null;
        }
        active = false;
    }

    private final class AutoFocusTask extends AsyncTask<Object, Object, Object> {
        @Override
        protected Object doInBackground(Object... voids) {
//      try {
//        Thread.sleep(AUTO_FOCUS_INTERVAL_MS);
//      } catch (InterruptedException e) {
//        // continue
//      }
            synchronized (AutoFocusManager.this) {
                if (active) {
                    start();
                }
            }
            return null;
        }
    }

}

Java Source Code List

• Back to App/code  ↑