title: Android Swipe to change fragments not working
body: <p>I am trying to make an app where a user can swipe and change which fragment they are seeing on the screen. I can not use view pager because I want the user to be able to swipe to different fragments forever. Here is the detector in my fragment:</p>
  
  <pre><code> class MyGestureDetector extends SimpleOnGestureListener {
              @Override
              public boolean onDown(MotionEvent e) {
              return true;
          }
          @Override
          public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
                  if(e1.getX() - e2.getX() &gt; SWIPE_MIN_DISTANCE &amp; Math.abs(velocityX) &gt; 10) {
                      left();
                  }  else if (e2.getX() - e1.getX() &gt; SWIPE_MIN_DISTANCE &amp; Math.abs(velocityX) &gt; 10) {
                      right();
                  }
  
              return false;
          }
              @Override
              public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY){
                    if(e1.getX() - e2.getX() &gt; SWIPE_MIN_DISTANCE &amp; distanceX &gt; distanceY) {
                      left();
                    }  else if (e2.getX() - e1.getX() &gt; SWIPE_MIN_DISTANCE &amp; distanceX &gt; distanceY) {
                        right();
                    }
                  return false;
              }
      }
      public void right(){
          mCallback.dateNumber(true);
          sportView.setText("Loading");
      }public void left(){
          mCallback.dateNumber(false);
          sportView.setText("Loading");
      }
  </code></pre>
  
  <p>In my activity, here is the listener that I added to change fragments:</p>
  
  <pre><code>                    @Override
              public void dateNumber(Boolean left_right) {
                  //true == right
                  //false == left
                  if(left_right == false){
                      day = day + 1;
                      Fragment1 rightFragment = new Fragment1();
                      Bundle args = new Bundle();
                      args.putInt("day", day);
                      rightFragment.setArguments(args);
  
                      android.support.v4.app.FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
                      transaction.replace(R.id.fragment_container, rightFragment);
                      transaction.addToBackStack(null);
                      transaction.commit();
                  }else if(left_right == true){
                      day = day - 1;
                      Fragment1 leftFragment = new Fragment1();
                      Bundle args = new Bundle();
                      args.putInt("day", day);
                      leftFragment.setArguments(args);
  
                      android.support.v4.app.FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
                      transaction.replace(R.id.fragment_container, leftFragment);
                      transaction.addToBackStack(null);
                      transaction.commit();
                  }
                  left_right = null;
              }
  </code></pre>
  
  <p>I know that the swipe gesture is always being recognized but sometimes the new fragment won't open up. Does anyone know why?</p>