Codice per gli intervalli minimo e massimo tramite SeekBar.

Codice definitivo per gli intervalli minimo e massimo:

public class MainActivity extends Activity {

 SeekBar seekBar1, seekBar2;
 TextView textView,textView2;
 int step;
 @Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_main);
  
  step=15;
  textView=(TextView)findViewById(R.id.textView1);
  textView2=(TextView)findViewById(R.id.textView2);
  
  seekBar1=(SeekBar)findViewById(R.id.seekBar1);
  seekBar2=(SeekBar)findViewById(R.id.seekBar2);
  
  seekBar1.setMax(60*4);
  seekBar2.setMax(60*4);
  
  

  textView.setText(0+" "+0);
  textView2.setText(0+" "+0);

  
  seekBar1.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
   
   @Override
   public void onStopTrackingTouch(SeekBar seekBar) {
    
   }
   
   @Override
   public void onStartTrackingTouch(SeekBar seekBar) {
    // TODO Auto-generated method stub
    
   }
   
   @Override
   public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
    int numero=step*(progress/step);
    int ore=numero/60;
    int minuti=numero%60;
    textView.setText(ore+" "+minuti);
    if(progress>seekBar2.getProgress()) seekBar2.setProgress(progress);
   }
  });
  
  seekBar2.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
   
   @Override
   public void onStopTrackingTouch(SeekBar seekBar) {
    // TODO Auto-generated method stub
    
   }
   
   @Override
   public void onStartTrackingTouch(SeekBar seekBar) {
    // TODO Auto-generated method stub
    
   }
   
   @Override
   public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
    int numero=step*(progress/step);
    int ore=numero/60;
    int minuti=numero%60;
    textView2.setText(ore+" "+minuti);
    if(progress<seekBar1.getProgress()) seekBar1.setProgress(progress);
    
   }
  });
 }

}