ReferenceError in qt quick controls tabview

Question

My code consistently gives me a ReferenceError. I have tried to fix this by using

tv.b1Text = " XD "

as in the example, but it didn't work. How can I fix this error? I believe there's a similar problem here.

Here's my code:

Button {
     id: b0
     text:"b1's text"
     onClicked: {
      b1.text = " XD "
     }
 }
TabView {
    id: tv
    Tab {
       id: tab1
       grid {
          Button{
              id: b1
              text:"b1's text"
              onClicked: {
                //console.log(b1.text)
                show_text()
              }
          }
       }
    }
}

Answer 1

You have a hierarchy in place here and specific scopes. You cannot access ids without exposing them to higher scopes or without going through the hierarchy, but in the correct way.

Let's examine your TabView: it has a single Tab element which contains a Grid (I'm assuming the grid element is actually a Grid!) which in turns contains the Button you want to modify. If you want to access it from Button b0 you have to:

1. Select the tab in tv
2. Select the contained item (via the property of the same name) --> it is Grid
3. Select the first item of the Grid (which is the only one, our Button)

Hence, in the current setting, a correct code to modify your b1 text from b0 clicked signal handler, is the following:

tv.getTab(0).item.children[0].text = " XD "

Note that data[0] can be used in place of children[0] (see the Item element docs). As you can see here you navigate the hierarchy to reach the QML element to be modified.

---

As you have seen, the previous code is tedious and error prone. A much better approach would be using the aliasing feature as well as Javascript to improve the overall result; other users already kindly advised you about that.