I'm trying to read information from a database of U1db.
I encountered this error
'ReferenceError: contents is not defined'
Here's my code:

    import U1db 1.0 as U1db
    U1db.Database {
            id: db
            path: "lU1DbDatabase"
    U1db.Document {
            id: doc
            database: db
            docId: 'doc1'
            create: true
            defaults: { "name":["Jerusalem"]}
            database: db
            id: index1
            expression: [["name"]]
            id: query1
            index: index1
     OptionSelector {
                delegate: OptionSelectorDelegate {
                                    text: i18n.tr(contents.name)//this work perfect
                onSelectedIndexChanged: {
                    console.log(contents.name);//this get the error!

this is part of large code that i cut the part that cause the problem.
what am i doing wrong? thank you!


Your problem is not with U1DB, but with the OptionSelector. Let's consider a simpler example:

import QtQuick 2.0
import Ubuntu.Components 1.0

MainView {
    OptionSelector {
        model: ListModel {
            ListElement { name: "Item 1" }
            ListElement { name: "Item 2" }
        delegate: OptionSelectorDelegate {
            text: i18n.tr(name)
        onSelectedIndexChanged: {

When the index is changed, we get the error, "ReferenceError: name is not defined". And why would we expect it to be defined? We've defined no variable named "name", and the OptionSelector doesn't have a "name" property.

Why can we reference "name" in the delegate? A new object is created from the delegate for each element in the model. This object gets the properties from that list element, and our list elements contain a "name" property. Similarly, in your example, the U1db.Query produced list elements with a "contents" property, which evidently was an object with a "name" property.

If we want to reference those properties outside of the delegate, we need to reach into the model and extract them:


In your case, the model is a U1db.Query, not a ListModel, so it doesn't have a get() method. It does have a results list that I presume you can index, but I don't know enough about U1db to say more. Hopefully this is enough to get you on the right path.

  • Thank you for your answer, this line has solved the problem for me: var doc = loacationDatabase.getDoc(model.documents[selectedIndex]); it stores the whole document into a variable and then I can read all the data. i think this is the best solution that i have. May 28 '15 at 5:38
  • or just model.results[selectedIndex].name[0] May 28 '15 at 6:06

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