Cascades Development

[HuXu77]

I would like to get more information on the correct way to do this with Cascades.  I am looking for a way to basically have:

TextField {
     text: user.weight
}

Button {
      text: "Plus 1"
      onClicked: {
             user.setWeight(user.weight + 1);
      }
}

 And the textfield automatically display the new value.  I understand it is simple by writing in a textfield id and doing id.text = user.weight; but I am going to have dynamically changing listviews and several other textfields and if I could avoid having to write "rebinding" methods for all of them that would be awesome.  But if this feature is not yet implemented in Cascades then I will go with writing the rebinding for now.  Just wanted to make sure before I started that thats the only option.

[smacmartin]

See sample cascadescookbookqml, Slider.

Stuart

[HuXu77]

Right that, I can do but the issue comes with when I have backend C++ changes, such as 

QML:

TextField {

      text: user.weight

}

C++:

qml->setContextProperty("user", userObject);

qml->setContextProperty("appContext", this);

if I have

QML:

Button {

     onClicked: {

            appContext.increaseWeight();

     }

}

C++:

public MyApp::increaseWeight() {

      user.setWeight(user.weight + 1);

}

The weight value increases in the user object but is not reflected in the UI until I do something to set the text to the new value.  Basically I am looking for an observer that will watch the bound variables for changes on the C++ side, and then update the UI when the change happens.

[smacmartin]

Excellent!

This is where signals and slots come into play.

The data model signals a change.

You want a controller that catches the change and updates its minions (the views).

That keeps the loose coupling between data model and UI that you want.

Stuart

[smacmartin]

Did you succeed?

Stuart

[AlterX]

Using signals you can resolve all of that!