WebcamsGrid.java :  » Web » webcams-viewer » com » android » webcamsViewer » Android Open Source

package com.android.webcamsViewer;

import android.app.Activity;
import android.app.AlertDialog;
import android.app.Dialog;
import android.app.ProgressDialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.graphics.Bitmap;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.GridView;
import android.widget.ListAdapter;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.AdapterView.OnItemLongClickListener;

public class WebcamsGrid extends Activity {
  // Static attributes
  /** Actions **/
  private static final int WEBCAM_ADDER = 0;
  private static final int WEBCAM_VIEW = 1;
  private static final int WEBCAM_REMOVE = 2;
  private static final int WEBCAMS_REFRESH = 3;
  private static final int APP_CLOSE = 4;
  /** Dialogs **/
  private static final int PROGRESS_DIALOG = 1;
  private static final int REMOVE_DIALOG = 2;

  private static final String TAG = "WebcamsGrid";

  // Attributes
  private GridView gridview = null;
  private ImageAdapter adp = null;
  private ProgressDialog progressDialog;
  private AlertDialog alertDialog;
  private int position = 0;
  private WebcamList list = null;

  /** Called when the activity is first created. */
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    // Check length list images
    list = new WebcamList(this);
    launchActivity(WEBCAMS_REFRESH);
  }

  /**
   * Handler event onCreateOptionsMenu
   */
  public boolean onCreateOptionsMenu(Menu menu) {
    MenuInflater inflater = getMenuInflater();
    inflater.inflate(R.menu.menu_main, menu);
    return true;
  }

  /**
   * Handler event onOptionsItemSelect
   */
  public boolean onOptionsItemSelected(MenuItem item) {
    // Handle item selection
    switch (item.getItemId()) {

    // Create new activity with add form
    case R.id.add:
      launchActivity(WEBCAM_ADDER);
      return true;

      // Refresh Images Grid
    case R.id.refresh:
      launchActivity(WEBCAMS_REFRESH);
      return true;

      // Stop app
    case R.id.quit:
      launchActivity(APP_CLOSE);
      return true;
    default:
      return super.onOptionsItemSelected(item);
    }
  }

  /**
   * Handler when activity finish
   */
  protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    // If data is null, UI should not be updated
    if(data != null) {
      switch (requestCode) {
      case WEBCAM_ADDER:
        // Refresh images grid when an image was added
        launchActivity(WEBCAMS_REFRESH);
        return;
      case WEBCAM_VIEW:
        launchActivity(WEBCAMS_REFRESH);
        return;
      default:
        return;
      }
    }
  }

  /**
   * Manager create dialog
   */
  protected Dialog onCreateDialog(int id) {
    switch (id) {
    case PROGRESS_DIALOG:
      progressDialog = new ProgressDialog(WebcamsGrid.this);
      progressDialog.setMessage(getText(R.string.loading));
      return progressDialog;
    case REMOVE_DIALOG:
      AlertDialog.Builder builder = new AlertDialog.Builder(this);
      builder.setMessage(getText(R.string.msgRemove));
      builder.setCancelable(false);
      builder.setPositiveButton(getText(R.string.yes),
          new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface dialog, int id) {
              dialog.dismiss();
              launchActivity(WEBCAM_REMOVE);
            }
          });
      builder.setNegativeButton(getText(R.string.no),
          new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface dialog, int id) {
              dialog.cancel();
            }
          });
      alertDialog = builder.create();
      return alertDialog;
    default:
      return null;
    }
  }

  /**
   * Launch a new activity
   * 
   * @param activity
   *            Id Activity
   */
  protected void launchActivity(int activity) {
    Intent i = null;
    switch (activity) {
    case WEBCAM_ADDER:
      i = new Intent(this, WebcamAdder.class);
      i.putExtra("position", -1);
      startActivityForResult(i, WEBCAM_ADDER);
      return;
    case WEBCAM_VIEW:
      i = new Intent(this, WebcamView.class);
      i.putExtra("position", position);
      startActivityForResult(i, WEBCAM_VIEW);
      return;
    case WEBCAM_REMOVE:
      // Update position
      WebcamList list = new WebcamList(WebcamsGrid.this);
      list.removeWebcam(position);
      launchActivity(WEBCAMS_REFRESH);
      return;
    case WEBCAMS_REFRESH:
      onRefresh();
      return;
    case APP_CLOSE:
      super.finish();
      this.finish();
      return;
    default:
      return;
    }

  }

  /**
   * Refresh Webcams Grid
   */
  protected void onRefresh() {
    if (list.getLength() > 0) {
      // Reset list content
      list.reset();

      setContentView(R.layout.main);

      // Free memory
      if (adp != null) {
        try {
          adp.finalize();
        } catch (Throwable e) {
          Log.d(TAG, "Error to free memory", e);
        }
      }

      // Create a new image adapter
      adp = new ImageAdapter(this.getApplicationContext());

      // Download images files asynchronously
      ResetGridViewTask task = new ResetGridViewTask();
      task.execute();

      // Set grid view
      gridview = (GridView) findViewById(R.id.gridview);
      gridview.setAdapter(adp);

      // New Activity to show Maximized Image
      gridview.setOnItemClickListener(new OnItemClickListener() {
        public void onItemClick(AdapterView<?> parent, View v, int pos,
            long id) {
          position = pos;
          launchActivity(WEBCAM_VIEW);
        }
      });

      // Dialog to remove image
      gridview.setOnItemLongClickListener(new OnItemLongClickListener() {
        public boolean onItemLongClick(AdapterView<?> parent, View v,
            int pos, long id) {
          position = pos;
          showDialog(REMOVE_DIALOG);
          return true;
        }
      });
    } else {
      setContentView(R.layout.noimages);
    }
  }

  /**
   * SetProgress ProgressDialog Handler
   */
  public void setProgress(Bitmap bm) {
    adp.addImage(bm);
    gridview.invalidateViews();
  }

  /**
   * Asynchronous task to starts a grid view
   */
  public class ResetGridViewTask extends AsyncTask<String, Bitmap, Bitmap[]> {

    /**
     * Handler onPreExecute event
     */
    protected void onPreExecute() {
      // Create an new progress dialog
      showDialog(PROGRESS_DIALOG);
    }

    /**
     * Method executed in background thread
     */
    protected Bitmap[] doInBackground(String... params) {
      Bitmap[] images = new Bitmap[list.getLength()];
      ImageLoader imgLoader = new ImageLoader();

      for (int i = 0; i < list.getLength(); i++) {
        Bitmap bm = imgLoader.loader(list.getWebcam(i).getUrl());
        images[i] = bm;
        publishProgress(bm);
      }
      return images;
    }

    /**
     * Handler on Progress Update
     */
    protected void onProgressUpdate(Bitmap... values) {
      super.onProgressUpdate(values);
      setProgress(values[0]);
    }

    /**
     * Handler onPostExecuteEvent
     */
    protected void onPostExecute(Bitmap[] result) {
      super.onPostExecute(result);
      // Hide Progress Dialog
      dismissDialog(PROGRESS_DIALOG);
    }
  }
}