Touch handling difference between prototyper and hardware

Question

Good day,

I have a simple touch handler on top of a slide handler. The simple touch handler has the following retarget specifications:

.RetargetCondition = Core::RetargetReason[WipeDown, WipeLeft, WipeRight, WipeUp]

.RetargetOffset = 10

.RetargetDelay = 1

In the prototyper

* A slide motion riases the slide event within the slide handler

* A press action raised the pressed event within the simple touch handler

 

But as soon as I take this to the hardware, the slide motion (even a fast motion) always raises the pressed event first and then the slide event.

Our hardware is healthy, and servises the EW application timeously.

Is this a bug in EW? Is it just the reality of things working out on paper but the real world has extra considerations that I need to know about?

 

I have 2 videos, as well as the EW project if you like, but I will need an email address or something to send it to,

 

Kind Regards,

Rob

Comments

Hi Manfred,

Thanks for the prompt response. I'll have a look. I receive a single event for press, and then a single event for release,

Kind Regards,

Rob

---

Hi Manfred,

Just to confirm, it is as you say. Single press event, multiple move events and Single release event are fed into EW. I logged to a buffer and verified this.

My code is from the STM32F469-DISCO example, and whilst it does not look exactly the same as yours, the result is the same.

Rob

Answer 1

Hi Rob,

in principle the different touch handlers and the retargetting is working fine - also on a real hardware.

Maybe the problem is more related to the system integration (on your particular hardware) or to the touch driver of your hardware. What target are you using?

You can modify the code sequence within your main loop, in order to analyze the touch sequences that are feed into the Embedded Wizard GUI application.

    /* Step 3: Receive cursor inputs (mouse/touch events)... */
    touch = GetTouchPosition( &point );

    /* ...and provide it to the application. */
    if ( touch > 0 )
    {
      /* Begin of touch cycle */
      if ( touch == 1 )
      {
        EwPrint( "Down\n" );
        events |= CoreRoot__DriveCursorHitting( rootObject, 1, 0, pos );
      }

      /* Movement during touch cycle */
      else if ( touch == 2 )
      {
        EwPrint( "Move\n" );
        events |= CoreRoot__DriveCursorMovement( rootObject, pos );
      }

      /* End of touch cycle */
      else if ( touch == 3 )
      {
        EwPrint( "Up\n" );
        events |= CoreRoot__DriveCursorHitting( rootObject, 0, 0, pos );
      }
    }

When you now make one slide gesture, do you get only one 'Down' - 'Move'....'Move' - 'Up' sequence or are there several 'Down' / 'Up' events?

Best regards,

Manfred.

Comments

Hi Manfred, I accept that. Can you say what I am doing incorrectly here? I'm wanting the simple touch to be retargetted due to the swipe motion.

.RetargetOffset = 10
.RetargetDelay = 1

 

Should .RetargetDelay be zero to avoid an instantaneous onPress?

---

Hi Rob,

please consider:

(1) You have a simple touch handler on top and you are touching the screen => Pressed.

(2) Now you slide on the screen => Release the simpel touch handler and start of slide touch cycle.

After (1) it cannot be foreseen if you want to start a slide gesture (2) or if you release the screen.

In case you do not want to react on the 'press' event, you can use the 'hold' event and evaluate the HoldPeriod of the touch handler.

Hope this helps...

Manfred.

---

Hi Manfred,

I've noted what you say about the prototyper raising the touch event.

A screen full of buttons with the requirement to swipe to another screen is a common requirement.

Would you recommend what you suggested in your last post as the optimal way (regarding usability) to go about this, of do you think it would be better to place the slide handler in front of the simple touch handler and Retarget after a delay ?

Kind Regards,

Rob

---

Hi Rob,

in case of buttons that are placed on a component that should be scrolled you can make different implementations. In the simplest case you place the buttons (including their simple touch handler) over the panel with its slide touch handler. As a result, the user can press on the buttons or slide the panel, as soon as he touches outside the buttons.

If it should be possible to slide the panel everywhere, you need to redirect the move gesture from the buttons to the panel. In this case:

Implement your buttons including a simple touch handler. As soon as the button is pressed, the button just appears pressed, without starting the buttons action. The action of the button will be signaled, when the user releases the button and the cursor event is not deflected.

Using the RetargetCondition of the button makes it possible to forward the touch event to the underlying panel.

Best regards,

Manfred.

---

Thanks Manfred, I came right.

The slide handler is placed behind the button touch handlers, so that the button touch handler services the event first. When the press is detected, a flag is set, and a timer started for 50ms. If the buttons onDrag event occurs within that time frame, then the flag is cleared, and the press event is ignored. The button touch handler also retargets to the slide touch handler, so that it can service the movement. If after 50ms, no onDrag event is generated, then the buttons action is executed