Skip to content
  • Categories
  • Recent
  • Tags
  • Popular
  • Users
  • Groups
  • Search
  • Get Qt Extensions
  • Unsolved
Collapse
Brand Logo
  1. Home
  2. Qt Development
  3. QML and Qt Quick
  4. A basic Question
Forum Updated to NodeBB v4.3 + New Features

A basic Question

Scheduled Pinned Locked Moved Solved QML and Qt Quick
qmlstyesheet
30 Posts 5 Posters 12.7k Views 3 Watching
  • Oldest to Newest
  • Newest to Oldest
  • Most Votes
Reply
  • Reply as topic
Log in to reply
This topic has been deleted. Only users with topic management privileges can see it.
  • S Offline
    S Offline
    sierdzio
    Moderators
    wrote on 26 Sept 2017, 04:11 last edited by
    #20

    Heh, actually the first version of my snipped used the question mark notation, but I changed it to if-else because I thought it would be more readable.

    It is definitely a good approach, and for simple cases I would recommend it - QML engine can optimize the question mark operator more heavily than if-else.

    (Z(:^

    1 Reply Last reply
    1
    • M Offline
      M Offline
      mrjj
      Lifetime Qt Champion
      wrote on 26 Sept 2017, 06:21 last edited by
      #21

      hi
      oh my gosh, is that like a c++ ternary operator that can be nested ?
      But its not super readable unless really short.

      1 Reply Last reply
      0
      • G Offline
        G Offline
        GrecKo
        Qt Champions 2018
        wrote on 26 Sept 2017, 07:10 last edited by
        #22

        It's the same, a c++ ternary operator can be nested.

        M 1 Reply Last reply 26 Sept 2017, 07:17
        0
        • G GrecKo
          26 Sept 2017, 07:10

          It's the same, a c++ ternary operator can be nested.

          M Offline
          M Offline
          mrjj
          Lifetime Qt Champion
          wrote on 26 Sept 2017, 07:17 last edited by
          #23

          @GrecKo
          Yep, i realized that after asking but I think i never saw one in c++
          like
          !m_seedsfilter ? good=true : m_seedsfilter==1 ? good=newClusters(Sp) : good=newSeed(Sp);

          (ugly as hell)

          1 Reply Last reply
          0
          • G Offline
            G Offline
            GrecKo
            Qt Champions 2018
            wrote on 26 Sept 2017, 07:22 last edited by
            #24

            Off-topic but it would be good = !m_seedsfilter? true : m_seedsfilter == 1 ? newClusters(Sp) : newSeed(Sp);, it's the same notation in Js and in c++

            1 Reply Last reply
            1
            • M Offline
              M Offline
              mrjj
              Lifetime Qt Champion
              wrote on 26 Sept 2017, 07:27 last edited by
              #25

              Thanks
              but was just live sample from
              https://stackoverflow.com/questions/18237432/how-to-rewrite-complicated-lines-of-c-code-nested-ternary-operator/18237507
              But back to topic a bit.

              Do you know how much of JS that is supported in QML ?
              Can i include .js stuff ?

              S 1 Reply Last reply 26 Sept 2017, 07:38
              0
              • M mrjj
                26 Sept 2017, 07:27

                Thanks
                but was just live sample from
                https://stackoverflow.com/questions/18237432/how-to-rewrite-complicated-lines-of-c-code-nested-ternary-operator/18237507
                But back to topic a bit.

                Do you know how much of JS that is supported in QML ?
                Can i include .js stuff ?

                S Offline
                S Offline
                sierdzio
                Moderators
                wrote on 26 Sept 2017, 07:38 last edited by
                #26

                @mrjj said in A basic Question:

                Do you know how much of JS that is supported in QML ?
                Can i include .js stuff ?

                I think V4 engine implements full ECMA 5.1 specs, so you can run any JavaScript there, unless it uses newer features.

                (Z(:^

                M 1 Reply Last reply 26 Sept 2017, 07:46
                0
                • S sierdzio
                  26 Sept 2017, 07:38

                  @mrjj said in A basic Question:

                  Do you know how much of JS that is supported in QML ?
                  Can i include .js stuff ?

                  I think V4 engine implements full ECMA 5.1 specs, so you can run any JavaScript there, unless it uses newer features.

                  M Offline
                  M Offline
                  mrjj
                  Lifetime Qt Champion
                  wrote on 26 Sept 2017, 07:46 last edited by
                  #27

                  @sierdzio said in A basic Question:

                  ECMA 5.1 specs

                  so that is pretty old ?
                  5.1 Edition / June 2011
                  https://www.ecma-international.org/ecma-262/5.1/

                  So most from
                  https://www.javascripting.com/

                  might not work as 6 years in Web tech is a decade ?

                  1 Reply Last reply
                  0
                  • S Offline
                    S Offline
                    sierdzio
                    Moderators
                    wrote on 26 Sept 2017, 07:51 last edited by
                    #28

                    It is old, indeed. But a lot of projects like node.js, charts.js etc. seem to be working (or used to work 1-2 years back).

                    There is a ticket for upgrading the engine, but it lays dormant since years https://bugreports.qt.io/browse/QTBUG-47735

                    (Z(:^

                    M 1 Reply Last reply 26 Sept 2017, 08:54
                    1
                    • S sierdzio
                      26 Sept 2017, 07:51

                      It is old, indeed. But a lot of projects like node.js, charts.js etc. seem to be working (or used to work 1-2 years back).

                      There is a ticket for upgrading the engine, but it lays dormant since years https://bugreports.qt.io/browse/QTBUG-47735

                      M Offline
                      M Offline
                      mrjj
                      Lifetime Qt Champion
                      wrote on 26 Sept 2017, 08:54 last edited by
                      #29

                      @sierdzio

                      Ok sounds pretty good. even if older.

                      It is odd that its not been updated since lots of activities on QML.

                      Thank you for all the info :)

                      S 1 Reply Last reply 26 Sept 2017, 09:14
                      0
                      • M mrjj
                        26 Sept 2017, 08:54

                        @sierdzio

                        Ok sounds pretty good. even if older.

                        It is odd that its not been updated since lots of activities on QML.

                        Thank you for all the info :)

                        S Offline
                        S Offline
                        sierdzio
                        Moderators
                        wrote on 26 Sept 2017, 09:14 last edited by
                        #30

                        @mrjj said in A basic Question:

                        It is odd that its not been updated since lots of activities on QML.

                        There was a discussion about it on the mailing list once. If I recall it correctly, the priority for Qt devs working on QML was to keep the engine fast, and make it work 100% reliable in common QML use cases (and the most common uses are: small bindings/ assignments and short functions) - so they did not feel pressure to implement newer features.

                        (Z(:^

                        1 Reply Last reply
                        0

                        29/30

                        26 Sept 2017, 08:54

                        • Login

                        • Login or register to search.
                        29 out of 30
                        • First post
                          29/30
                          Last post
                        0
                        • Categories
                        • Recent
                        • Tags
                        • Popular
                        • Users
                        • Groups
                        • Search
                        • Get Qt Extensions
                        • Unsolved