Android Open Source - lucene Async Image Loader

• Back to App/tablet  ↑

From Project

Back to project page lucene.

License

The source code is released under:

GNU General Public License

Java Source Code

/**
 * Copyright (C) 2011-2012 Takahiro Yoshimura
 */*  w w  w.  ja v  a 2 s  .c  om*/
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * In addition, as a special exception, the copyright holders give
 * permission to link the code of portions of this program with the
 * AdMob library under certain conditions as described in each
 * individual source file, and distribute linked combinations
 * including the two.
 *
 * You must obey the GNU General Public License in all respects for
 * all of the code used other than AdMob.  If you modify file(s) with
 * this exception, you may extend this exception to your version of
 * the file(s), but you are not obligated to do so.  If you do not
 * wish to do so, delete this exception statement from your version.
 * If you delete this exception statement from all source files in the
 * program, then also delete it here.
 */

package com.gmail.altakey.lucene;

import android.os.Bundle;
import android.os.AsyncTask;
import android.app.ProgressDialog;
import android.widget.*;
import android.view.*;
import android.util.*;
import android.content.*;
import android.content.res.Resources;
import android.graphics.*;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.ColorDrawable;
import android.net.*;
import android.net.http.AndroidHttpClient;
import org.apache.http.client.methods.HttpGet;
import java.io.*;

public final class AsyncImageLoader extends AsyncTask<Void, Long, BitmapDrawable>
{
  public interface Callback
  {
    public void onComplete();
    public void onError();
  }

  private final static Callback NullCallback = new Callback()
  {
    public void onComplete()
    {
    }

    public void onError()
    {
    }
  };
  
  private final Intent intent;
  private final HWImageView view;
  private final AsyncImageLoader.Callback cb;

  private ProgressDialog progress;
  private Toast oomMessage;
  private AndroidHttpClient httpClient;

  public AsyncImageLoader(final HWImageView v, final Intent intent, final AsyncImageLoader.Callback cb)
  {
    this.view = v;
    this.intent = intent;
    if (cb != null)
      this.cb = cb;
    else
      this.cb = NullCallback;
  }

  public static AsyncImageLoader create(final HWImageView v, final Intent intent)
  {
    return create(v, intent, null);
  }

  public static AsyncImageLoader create(final HWImageView v, final Intent intent, final AsyncImageLoader.Callback cb)
  {
    return new AsyncImageLoader(v, intent, cb);
  }

  protected void onPreExecute()
  {
    Context context = this.view.getContext();
    this.httpClient = AndroidHttpClient.newInstance(this.getUserAgent());
    this.oomMessage = Toast.makeText(context, R.string.toast_out_of_memory, Toast.LENGTH_SHORT);
    this.progress = new ProgressDialog(context);
    this.progress.setTitle(context.getString(R.string.dialog_loading_title));
    this.progress.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
    this.progress.setMessage(context.getString(R.string.dialog_loading_message));
    this.progress.show();

    ImageUnloader.unload(this.view);
  }

  private String getUserAgent()
  {
    Context context = this.view.getContext();
    return String.format("%s/%s", context.getString(R.string.app_name), context.getString(R.string.app_version));
  }

  protected void onProgressUpdate(Long... args)
  {
    int at = args[0].intValue();
    int size = args[1].intValue();
    boolean indeterminate = (size <= 0);

    this.progress.setIndeterminate(indeterminate);
    if (!indeterminate)
    {
      this.progress.setMax(size / 1024);
      this.progress.setProgress(at / 1024);
    }
    else
      this.progress.setProgress(0);
  }

  protected void onPostExecute(BitmapDrawable bitmap)
  {
    if (bitmap != null)
    {
      this.view.setImageDrawable(bitmap);
      this.cb.onComplete();
    }
    else
    {
      this.cb.onError();
    }
    this.progress.dismiss();
    this.httpClient.close();
  }

  protected BitmapDrawable doInBackground(Void... args)
  {
    final Context context = this.view.getContext();
    final Resources res = context.getResources();

    try
    {
      InputStream in = this.read(new ProgressReportingInputStream.ProgressListener() {
        public void onAdvance(long at, long size)
        {
          publishProgress(at, size);
        }
      });
      BitmapFactory.Options bfo = new BitmapFactory.Options();
      bfo.inDither = true;
      bfo.inPreferredConfig = Bitmap.Config.RGB_565;
      try
      {
        bfo.inPreferQualityOverSpeed = true;
      }
      catch (NoSuchFieldError e)
      {
      }
      Bitmap bitmap = BitmapFactory.decodeStream(in, new Rect(-1,-1,-1,-1), bfo);
      return new BitmapDrawable(res, this.scale(bitmap));
    }
    catch (FileNotFoundException e)
    {
      return null;
    }
    catch (OutOfMemoryError e)
    {
      this.oomMessage.show();
      return null;
    }
  }

  private Bitmap scale(Bitmap src)
  {
    int width = src.getWidth();
    int height = src.getHeight();
    final int maxWidth = this.view.getAcceleration().getMaximumBitmapWidth();
    final int maxHeight = this.view.getAcceleration().getMaximumBitmapHeight();
    if (maxWidth < 0 || maxHeight < 0)
      return src;
    if (width < maxWidth && height < maxHeight)
      return src;
    
    if (width > height)
    {
      height = (int)(height * (maxWidth / (float)width));
      width = maxWidth;
    }
    if (width < height)
    {
      width = (int)(width * (maxHeight / (float)height));
      height = maxHeight;
    }
    Log.d("AIL", String.format("scaling: (%d, %d) -> (%d, %d)", src.getWidth(), src.getHeight(), width, height));
    return Bitmap.createScaledBitmap(src, width, height, true);    
  }

  private InputStream read() throws FileNotFoundException
  {
    return this.read(null);
  }

  private InputStream read(ProgressReportingInputStream.ProgressListener listener) throws FileNotFoundException
  {
    final Context context = this.view.getContext();

    if (Intent.ACTION_SEND.equals(this.intent.getAction()))
    {
      final Bundle extras = this.intent.getExtras();
      if (extras.containsKey(Intent.EXTRA_STREAM))
        return new ProgressReportingInputStream(context.getContentResolver().openInputStream((Uri)extras.getParcelable(Intent.EXTRA_STREAM)), listener);
      if (extras.containsKey(Intent.EXTRA_TEXT))
      {
        try
        {
          final HttpGet req = new HttpGet(extras.getCharSequence(Intent.EXTRA_TEXT).toString());
          return new ProgressReportingInputStream(this.httpClient.execute(req).getEntity().getContent(), listener);
        }
        catch (IllegalArgumentException e)
        {
          return null;
        }
        catch (IOException e)
        {
          return null;
        }
      }
    }

    if (Intent.ACTION_VIEW.equals(this.intent.getAction()))
      return new ProgressReportingInputStream(context.getContentResolver().openInputStream(this.intent.getData()), listener);

    return null;
  }
}

Java Source Code List

• Back to App/tablet  ↑