CommonThread.java :  » Utilities » tripcomputer » pl » tripcomputer » common » Android Open Source

package pl.tripcomputer.common;

import android.content.Context;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.Display;
import android.view.WindowManager;


public abstract class CommonThread extends Thread
{
  // fields
  protected Handler mHandler = null;
  protected Context mContext = null;
  private Display defaultDisplay = null;
  
  private volatile Boolean bIsActive = false;
  private volatile Boolean bEnabled = true;

  private static final Integer STATE_PAUSED = 0;
  private static final Integer STATE_RUNNING = 1;

  private Integer iState = STATE_PAUSED;
  
  private volatile Boolean bStateMutex = false; 
  private volatile Boolean bMutex = false; 

  
  // methods
  public CommonThread(Context context, Handler handler)
  {
    mHandler = handler;
    mContext = context;

    // get display
    final WindowManager winManager = (WindowManager)(mContext.getSystemService(Context.WINDOW_SERVICE));
    if (winManager != null)
      defaultDisplay = winManager.getDefaultDisplay();
  }

  public int getScreenOrientation()
  {
    if (defaultDisplay != null)
      return defaultDisplay.getOrientation();
    return 0;
  }

  // send message to main thread
  public boolean sendMessageToParent(Bundle bundle)
  {
    Message msg = mHandler.obtainMessage();
    msg.setData(bundle);
    return mHandler.sendMessage(msg);
  }

  public void createThread()
  {
    bIsActive = true;
    this.start();
  }

  public void destroyThread()
  {
    synchronized(bMutex)
    {
      bIsActive = false;
    }
    boolean bRetry = true;
    while (bRetry)
    {
      try
      {
        this.join();
        bRetry = false;
      } catch (InterruptedException e)
      {
      }
    }
  }

  public boolean isActive()
  {
    synchronized(bMutex)
    {
      return bIsActive;
    }
  }

  public void setEnabled(boolean bEnabled)
  {
    synchronized(bMutex)
    {
      this.bEnabled = bEnabled;
    }
  }
  
  public boolean isEnabled()
  {
    synchronized(bMutex)
    {
      return bEnabled;
    }
  }
  
  public void run()
  {
    onInitializeData();
    super.run();
  }

  public boolean isRunning()
  {
    boolean bValue = false;
    synchronized(bStateMutex)
    {
      bValue = (iState.equals(STATE_RUNNING));
    }
    return bValue;
  }
  
  public void setStateRunning()
  {
    setState(STATE_RUNNING);  
  }
  
  public void setStatePaused()
  {
    setState(STATE_PAUSED);  
  }

  private void setState(Integer state)
  {
    if (!isActive())
      return;
    
    synchronized(bStateMutex)
    {  
      iState = state;
  
      if (iState.equals(STATE_PAUSED))
      {
        // pause thread here
      }
  
      if (iState.equals(STATE_RUNNING))
      {
        // resume thread here
      }
  
      onStateChanged();
    }
  }

  //done before run
  public abstract void onInitializeData();

  //done after state changed
  public abstract void onStateChanged();

}