title: getContentResolver() and getWindow() in a DialogFragment
body: <p>I'm trying to insert a SeekBar in a Dialog to change the brightness. To do this, I wrote this code.</p>
  
  <pre><code>public class Lum extends DialogFragment{
  
  
          private SeekBar brightbar;
          private int brightness;
          private ContentResolver cResolver;
          private Window window;
          TextView txtPerc;
          boolean stato;
          Context context;
  
          public android.app.Dialog onCreateDialog(Bundle savedInstanceState) {
              // Use the Builder class for convenient dialog construction
  
              AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
  
              LayoutInflater inflater = getActivity().getLayoutInflater();
              View view = inflater.inflate(R.layout.dialog_brightness, null);
              builder.setView(view);
  
          brightbar = (SeekBar) view.findViewById(R.id.brightbar);
          txtPerc = (TextView) view.findViewById(R.id.txtPercentage);
          //cResolver = getContentResolver();
          //window = getWindow();
          brightbar.setMax(255);
          brightbar.setKeyProgressIncrement(1);
  
          brightbar = (SeekBar) view.findViewById(R.id.brightbar);
          txtPerc = (TextView) view.findViewById(R.id.txtPercentage);
          cResolver = getContentResolver();
          window = getWindow();
          brightbar.setMax(255);
          brightbar.setKeyProgressIncrement(1);
  
          try {
              brightness = Settings.System.getInt(context.getContentResolver(), Settings.System.SCREEN_BRIGHTNESS);
          } catch (SettingNotFoundException e) {
              // TODO Auto-generated catch block
              e.printStackTrace();
          }
          float perc = (brightness /(float)255)*100;
          txtPerc.setText((int)perc +" %");
  
          brightbar.setProgress(brightness);
          brightbar.setOnSeekBarChangeListener(new OnSeekBarChangeListener()
          {
              public void onStopTrackingTouch(SeekBar seekBar)
              {
                  Settings.System.putInt(context.getContentResolver(), Settings.System.SCREEN_BRIGHTNESS, brightness);
                  LayoutParams layoutpars = window.getAttributes();
                  layoutpars.screenBrightness = brightness / (float)255;
                  window.setAttributes(layoutpars);
              }
  
              public void onStartTrackingTouch(SeekBar seekBar)
              {
  
              }
  
              public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser)
              {
  
  
                      brightness = progress;
  
                      float perc = (brightness /(float)255)*100;
                      txtPerc.setText((int)perc +" %");
              }
          });     
  
              builder.setTitle("Brightness")
                     .setPositiveButton("Close", new DialogInterface.OnClickListener() {
                         public void onClick(DialogInterface dialog, int id) {
                             dismiss();
      }
                     });
  
              // Create the AlertDialog object and return it
              return builder.create();
          }
      }
  </code></pre>
  
  <p>The problem is that my IDE Eclipse marks errors in getContentResolver and getWindow because I'm working on a DialogFragment and not an Activity. 
  How can I do to use this instruction in this class? Or, if you can not do that, there is an alternative? Thanks in advance</p>