how to disable a Button?

[bmarimuthu-2]

Hi,

I have 3 buttons ( port, baudrate and parity)  with respective dropdown list and one normal button "save".

After selecting the values from all those 3 buttons, my "save" button should enable. Till then it should be disabled.

How could I do this one?

[ankigupta · Accepted solution]

Bavithraa Marimuthu​,

One way could be to write a custom service which takes 3 input parameters and return Boolean false if none of the parameter is null else true.

Bind the selected value of all dropdown to this service and call this service on SelectedRowsChanged events of the list widgets.

Bind the output of the service to disabled property of the Button.

Disabled property of Button is initially selected.

I hope it helps.

[bmarimuthu-2]

How to call the service on selectedvalue changed of the list widgets?

Where to find that option?

[psethia-3]

You can trigger it on the SelectedRowsChanged event of the added service on the list widget. You can find it in the bottom right corner on the UI, please see below

Hope this is helpful!

[bmarimuthu-2]

see this is the code i have writen ,but getting "invalid  syntax format" error in line no:6

How to modify my code?

[ankigupta]

Hi Bavithraa Marimuthu​,

Try following:

[bmarimuthu-2]

I have followed all the steps as you suggested. But the button is "enabled" all the time. PFA, The screenshots of  my service and mashup. Please tell me where I commit mistake.

Figure (a):  See, even I have not provided any inputs my button is in "enabled" mode

Figure (b): ​​This is the service where I have binded everything.

Figure (c):​​ Refer figure (a) This is the dropdown values for the comm port button. similarly Baudrate and parity thave their own dropdown values.

Figure(d): This is the service I have used in my mashup.

[ankigupta]

Hi Bavithraa Marimuthu​,

Button is disabled when the disabled property is true. So, you need to reverse the result in condition in the service. Please check the image of service I had shared.

Here is the code for quick reference:

var result=true;
if(port != null && baudrate != null && parity != null) {
  result=false;
}

[bmarimuthu-2]

Now, initially it is in "disabled " mode. But even after selecting values also it is not enabled.

I think this is because of "selectedrowchange" event

[ankigupta]

Hi Bavithraa Marimuthu​,

Please bind the SelectedRowsChanged event of the three services (which are fetching data to the list widget) with the custom service so that the custom service is executed every time selected value changes in any of the list widget.

[bmarimuthu-2]

In list widget, where should I trigger the "selected changed row' event of my service.?

[ankigupta]

SelectedRowsChanged event is available in the service which feeds the list widget.

Click on the service in the right pane and event will show below in the right pane itself.

[bmarimuthu-2]

Its working fine now. Thanks Ankit

[bmarimuthu-2]

Now My another requirement is  after entering the values in dropdown list ,If I click on that enabled "save button" it should enable the "contiue" button

Overlayed on the save button.

How to do this?

[ankigupta]

Hi Bavithraa Marimuthu​,

Please check my reply on Thread how to disappear a button onclicking?

You can actually hide the continue button initially. Use an expression widget with returns true.

So, on click of save button; Save button will hide with an expression widget and Continue button will show up with another expression widget.

Do let me know if you face any issues.

[bmarimuthu-2]

Could you explain this in detail?

How to link save button  and continue button

[bmarimuthu-2]

on click of save button; Save button will hide with an expression widget and Continue button will show up with another expression widget.

How this can be done?

[ankigupta]

There are two Expression widget one returns true and other false.

Both are evaluated on click event of save button.

true expression will bind to visible property of continue (currently false) and false expression will bind to visible property of save (currently true).

So, on click of save button; save will hide and continue will show.

[bmarimuthu-2]

This works great!!! Thanks Ankit

[ankigupta]

I am glad it worked.