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Strange approach to properties

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propertiesqwidgetserializationmetadataqmetaobject
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  • SGaistS Offline
    SGaistS Offline
    SGaist
    Lifetime Qt Champion
    wrote on last edited by
    #2

    Hi,

    Because not all properties makes sense to be read/write. You can have for example a property representing the state of a piece of hardware. The hardware being the controller of the state, it wouldn't make sense for a library user to be able to set that state.

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    • SGaistS SGaist

      Hi,

      Because not all properties makes sense to be read/write. You can have for example a property representing the state of a piece of hardware. The hardware being the controller of the state, it wouldn't make sense for a library user to be able to set that state.

      W Offline
      W Offline
      Wilk
      wrote on last edited by
      #3

      @SGaist Well, you are right, not all properties make sense to read and write. But I think, that property like fullScreen is one of those, that one may want to write. Well, I want to write it)

      mrjjM 1 Reply Last reply
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      • W Wilk

        @SGaist Well, you are right, not all properties make sense to read and write. But I think, that property like fullScreen is one of those, that one may want to write. Well, I want to write it)

        mrjjM Offline
        mrjjM Offline
        mrjj
        Lifetime Qt Champion
        wrote on last edited by
        #4

        @Wilk
        well that is what
        http://doc.qt.io/qt-5/qwindow.html#setWindowState
        is for :)

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        • mrjjM mrjj

          @Wilk
          well that is what
          http://doc.qt.io/qt-5/qwindow.html#setWindowState
          is for :)

          W Offline
          W Offline
          Wilk
          wrote on last edited by
          #5

          @mrjj, I know about all other ways to make window fullscreen or set another window state. I'm talking about inability to make all those funny things with use of property system. Basically I'm veeery lazy, so I prefer to write a single piece of code that does everything instead of creating different code for handling different approaches to setting window state.

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          • W Offline
            W Offline
            Wilk
            wrote on last edited by
            #6

            For example, if everything is property, I can do the following:

            1. Serialize object state with a single call:
            QDomNode serializedObjectProperties = serialize (
            	this,
            	QObjectSerialization::TAG_OBJECT_NAME);
            

            serializedObjectProperties will be XML DOM element with tag name that's the same as object name stored in objectName property.
            2. Save serialized object state in XML file like this:

             <SomeWidget minimumHeight="0" toolTipDuration="-1" modal="false" focus="false" windowOpacity="1" styleSheet="" objectName="SomeWidget" autoFillBackground="true" windowModified="false" maximized="false" toolTip="" inputMethodHints="0" minimumWidth="0" isActiveWindow="false" height="1024" y="51" width="1280" accessibleDescription="" windowTitle="" enabled="true" font="MS Shell Dlg 2,8.25,-1,5,50,0,0,0,0,0" windowModality="0" statusTip="" contextMenuPolicy="1" fullScreen="true" accessibleName="" maximumWidth="16777215" visible="true" x="-1280" updatesEnabled="true" maximumHeight="16777215" mouseTracking="true" layoutDirection="0" windowFilePath="" focusPolicy="0" whatsThis="" acceptDrops="false" windowIconText="" minimized="false">
                    <property name="childrenRect">
                      <QRect y="0" width="0" x="0" height="0"/>
                    </property>
                    <property name="geometry">
                      <QRect y="51" width="1280" x="-1280" height="1024"/>
                    </property>
                    <property name="normalGeometry">
                      <QRect y="358" width="640" x="-1050" height="480"/>
                    </property>
                    <property name="frameGeometry">
                      <QRect y="51" width="1280" x="-1280" height="1024"/>
                    </property>
                    <property name="rect">
                      <QRect y="0" width="1280" x="0" height="1024"/>
                    </property>
                  </SomeWidget>
            
            1. Restore full object state with a single call:
            deserialize (
            	window,
            	serializedObjectProperties);
            

            I find it usefull as soon as I don't need to wary about anything as long as object state if fully described with it's properties.

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            • mrjjM Offline
              mrjjM Offline
              mrjj
              Lifetime Qt Champion
              wrote on last edited by mrjj
              #7

              Well, i understand.
              show() and hide() are not properties either so
              I guess they designed fullscreen to be a case of showíng and
              not a property. We are all lazy: )
              I just wish c++ had serialization system as default :)

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              • mrjjM mrjj

                Well, i understand.
                show() and hide() are not properties either so
                I guess they designed fullscreen to be a case of showíng and
                not a property. We are all lazy: )
                I just wish c++ had serialization system as default :)

                W Offline
                W Offline
                Wilk
                wrote on last edited by
                #8

                @mrjj
                With QObject properties serialization becomes realy easy. Well, some things in my implementation may be wrong or, you know, ugly, but for now it works quite fine. I think I'll put it on GitHub as soon as it will be ready enough.

                mrjjM 1 Reply Last reply
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                • W Wilk

                  @mrjj
                  With QObject properties serialization becomes realy easy. Well, some things in my implementation may be wrong or, you know, ugly, but for now it works quite fine. I think I'll put it on GitHub as soon as it will be ready enough.

                  mrjjM Offline
                  mrjjM Offline
                  mrjj
                  Lifetime Qt Champion
                  wrote on last edited by
                  #9

                  @Wilk
                  sounds cool. other will like to see such library.
                  Thank you

                  W 1 Reply Last reply
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                  • mrjjM mrjj

                    @Wilk
                    sounds cool. other will like to see such library.
                    Thank you

                    W Offline
                    W Offline
                    Wilk
                    wrote on last edited by
                    #10

                    @mrjj
                    You inspired me so I've commited my work on GitHub. The implementation is not good enough for production, I guess, and it's not packed as appropriate library, but it still may be usefull. As soon as I'll find time for it I'll try to make it a real library.

                    mrjjM 1 Reply Last reply
                    1
                    • W Wilk

                      @mrjj
                      You inspired me so I've commited my work on GitHub. The implementation is not good enough for production, I guess, and it's not packed as appropriate library, but it still may be usefull. As soon as I'll find time for it I'll try to make it a real library.

                      mrjjM Offline
                      mrjjM Offline
                      mrjj
                      Lifetime Qt Champion
                      wrote on last edited by
                      #11

                      @Wilk
                      Checked a few files. seems good quality.
                      Thank you.

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                      • mrjjM mrjj

                        @Wilk
                        Checked a few files. seems good quality.
                        Thank you.

                        W Offline
                        W Offline
                        Wilk
                        wrote on last edited by
                        #12

                        @mrjj Thanks)

                        1 Reply Last reply
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