Redirecting HMI from studio

[TCELE]

Hello,

Ive developed my project with multiple pages according to the tutorial with multiple .hmi.svg files which is working great.

The project includes a key switch that is supposed to open a setting page upon high edge. What would be the easiest way to redirect startx chromium-browser instance to a different page from a rexygen studio block. Im guessing running a bash command is the only way, but am totally lost at doing it this way.

TLDR: Chromium page redirection from a function block

[cechurat]

@tcele Hello Ivan,

thank you for your post. I would suggest to solve this request by means of REXYGEN HMI Designer. Just introduce another layer which will hide/show (Group Animation -> Opacity) according to the key switch digital signal.

Kind Regards,
Tomas

[TCELE]

@cechurat

So after implementing a solution with the hide_by option we are getting a bug where most input components set their state from ONLINE to ERROR, visually they are disabled (greyed out), after a short period of running. No other functional problems, just buttons/sliders not working.

HMI log set on TRACE option:

Periodic reading failed! Request 7559 timed out
State changed to ERROR (multiple times, for reach HMI component)
Request 7559 timed out
Remaining commands: 0 message length: 0
State changed to ONLINE (multiple times, for reach HMI component)
Periodic reading failed! Request 5038 timed out

Ive used the hide_by parameter in the same manner before without problems. Any idea to the cause? Thanks in advance!

[ondrej_severa]

@tcele
This behavior indicates that you are requesting too many datapoints and thus the read request is timeout. I suggest opening the SERVICE page on a different web page. You can do it by adding redirect request to custom javascript.

1. Create CUSTOM and CUSTOM/js folder in your hmisrc folder.
2. Create custom.js file in the CUSTOM/js folder
3. Open your page in HMI Designer, open HMI Configuration and in the HTML Export tab check Expert mode. Add two rows in the Library Path with GENERAL and CUSTOM texts. This will tell the HMI builder to include components from GENERAL library and your CUSTOM foilder. That how you append the custom.js file to your project
4. Edit the custom.js file with following content:

REX.HMI.init = function(){

let servis= REX.HMI.get('<name of the alias defined in HMI Designer>');
//or
let servis= // REX.HMI.add({alias:"servis",cstring:"task.block:parameter"}'alias defined in HMI Designer>'); // Add new item

// Subsribe to onChange event
servis.on('change',(itm)=>{
    // If true and not in the page redirect current page to servis page
   // The check for href is not necessary if only on used in index.html page
    if(itm.getValue() && window.location.href.indexof('servis.html') == -1 ){
        window.location.href = '/hmi/servis.html';
        // or open new tab
        // window.open('/hmi/servis.html','blank_');
    }
    else{
        // do nothing
    }
});
};

[TCELE]

@ondrej_severa
I have done as instructed, but I don't get redirected to the service.html page, I tried to use a button component as well as a slider component. Any more advice?

The reason behind this behaviour is correct, I think, when I set the refresh rate higher/slower it takes a longer time before the components get a timeout, but it still happens even on 500 ms (default).

[ondrej_severa]

@tcele
Are you sure, that your custom.js is included during the build? Please add alert('I am here') to your code and test if the alert occurs. I was told that you want to open this screen, whenever some operator switches some digital input. That's why my code requests servis data point and wait until the read value is non-zero. There is no need for a Button or Slider.

If you want you can send me the source for your HMI and I can check it for you.

Best regards
Ondrej

[TCELE]

@ondrej_severa

Hello,

The alert is there, custom.js is included. All the screens work now as before, it's just that the components that switch them time out after a short while and are disabled.

Ignoring that I also force switched to the servis.html but no page is there, I checked the directory over ssh too.

I've also updated rexygen studio to 2.50.10.13072, mentioning it just in case.

hmisrc.zip

[ondrej_severa]

@tcele
I have created a minimal working example and find out there is a little typo in my example source code

// indexOf
if(itm.getValue() && window.location.href.indexOf('servis.html') == -1 ){ 

After the fix, code is working fine for me. See the attachment.
BR
Ondrej
tcele.zip

[TCELE]

@ondrej_severa

Thanks for the example, it works as intended, I'm guessing, except that I am still missing the service.html and land on an Error 404 - Not Found page.

Any dependencies I could be missing? I am running your example on a new Raspbian lite image with fresh rex core and HMI chromium installation.

[ondrej_severa]

@tcele
You are almost done. The last step is to create new file in HMI Designer save it to hmisrc dir and name it servis.hmi.svg. You can design new screen in this file.

[TCELE]

@ondrej_severa

I believe there was a misunderstanding, the logic changing screens was already done with the hide_by parameters and worked, it's just that some components happened to be timing out. This didn't happen before in other projects done the same way.

Neverminding that, I reworked the project to use javascript as you suggested, I like the fact that .hmi.svg files are split, it keeps things organized. After some prolonged tests, there are no more timeouts.

There is one last flaw that I would like to work out. The chromium instance allows the user to use gestures and go back and forth in the history of pages. In some cases get to a restricted page this way.

I googled vigorously to solve this issue, but so far to no avail. Any advice on this topic?

Thanks for all the help so far!

chromium flags I tried:

--user-data-dir=/tmp/hmi-chromium
--kiosk
--incognito
--disable-pinch
--overscroll-history-navigation=0 #This should fix it but it doesn't
--disable-overscroll-edge-effect #Tried this one too
--no-sandbox
--start-fullscreen
--window-size=$SIZE
--window-position=0,0
--no-first-run
--disable-translate
--noerrdialogs
--disable-infobars
--disable-component-update

[cechurat]

@tcele said in Redirecting HMI from studio:

There is one last flaw that I would like to work out. The chromium instance allows the user to use gestures and go back and forth in the history of pages. In some cases get to a restricted page this way.
I googled vigorously to solve this issue, but so far to no avail. Any advice on this topic?

Hi Ivan,
I wasn't successful in finding any suitable solution as well. Have a look at xinput command which might help you to disable all the gestures at Linux level. I didn't tried it myself however if you find any working solution our team and the community will be happy to hear about it.

Cheers,
Tomas