Integrating Qt Quick components in Ministro

Chris Browet cbro at semperpax.com
Thu Feb 2 16:39:32 UTC 2012 

Definitely! I remember reading the blog post about the components for
desktop, but completely forgot about it...

On Thu, Feb 2, 2012 at 15:19, BogDan <bog_dan_ro at yahoo.com> wrote:

>
>
> Hi,
>
>     Excuse me if I'm wrong, but why we don't do the same technique as
> Nokia did with qml components for desktop ? They are using the application
> current QStyle plugin to paint all qml controls ! Is there any reason not
> to do the same thing ?
>
> Cheers,
> BogDan.
>
> >
> >
> >There is the possibility of encapsulating widgets in QGraphicItem (as
> QGraphicWidget), thus allowing them to be used in QML.
> >
> >I don't know how these QGraphicWidget's handle QStyle, though....
> >
> >- Chris -
> >
> >
> >On Thu, Feb 2, 2012 at 14:28, BogDan <bog_dan_ro at yahoo.com> wrote:
> >
> >
> >>
> >>Hi,
> >>
> >>
> >>Yes ! BorderImage seems to be exactly the same thing with NinePatch,
> thanks for the tip !
> >>
> >>
> >>   Anyway, as I said before I'd like to have a QStyle plugin which
> paints the classic widget also the qml ones, because it seems classic
> widgets are sill use by a lot of people !
> >>
> >>
> >>Cheers,
> >>
> >>BogDan.
> >>
> >>
> >>
> >>----- Original Message -----
> >>> From: Kate Alhola <kate.alhola at gmail.com>
> >>
> >>> Sent: Wednesday, February 1, 2012 10:59 PM
> >>> Subject: Re: Integrating Qt Quick components in Ministro
> >>>
> >>
> >>> Some quick look comments:
> >>>
> >>> On Wed, Feb 1, 2012 at 9:20 PM, BogDan <bog_dan_ro at yahoo.com> wrote:
> >>>>  Hello everyone,
> >>>>
> >>>>    I have good news on this topic, I manage to check (a little bit)
> >>> Android's source code and to extract, the exact, android's look and
> >>> style informations for a few widgets (buttonStyle, editTextStyle,
> >>> radioButtonStyle, checkboxStyle, etc.) and store them into a .json
> file (check
> >>> the attachment). Because qt 4.x doesn't come with json support, IMHO
> we have
> >>> two options:
> >>>>    1 - to use this [1] qt json implementation.
> >>>>    2 - or to backport Qt 5.x json implementation (my favorite option,
> >>> because it seems more complex and complete than the first one).
> >>>>
> >>>>    I need more time to finish the extraction class (which will be
> part of
> >>> the next Ministro release), so, if someone wants to step in and begin
> the Qt
> >>> implementation it will be very appreciated !
> >>>>
> >>>>    To understand how android paints the widgets you have to check a
> simple
> >>> widget how it's painted. So let's check Button class [2], which extends
> >>> TextView class [3] which extends the View class [4].
> >>>>
> >>>>  How it works:
> >>>>    - Button class only pass to its super class (TextView)  the style
> >>> attribute (com.android.internal.R.attr.buttonStyle)
> >>>>    - TextView class pass the same information to its super class
> (View) then
> >>> in its constructor (check "public TextView(Context context,
> AttributeSet
> >>> attrs, int defStyle)" ) extracts text informations
> >>> (e.g.TextAppearance_textColor,TextAppearance_textSize,
> TextAppearance_typeface,
> >>> etc.) which are used to draw the text (check onDraw (...)).
> >>>>    - View class in its constructor (check "public View(Context
> context,
> >>> AttributeSet attrs, int defStyle)") extracts a few informations e.g.
> >>> View_background, View_paddingLeft, etc. which are used to paint the
> basic parts
> >>> of the widget (e.g. the background).
> >>>>
> >>>>    If you check the json file, you'll see that there are more than one
> >>> .png files used to paint the background, one for every view state
> (enabled,
> >>> disabled, pressed, etc.). Android split every .png file into nine
> pieces (it
> >>> uses nine patch technique [5], [6]) which are used to seamlessly
> resize the
> >>> widget. AFAIK there is no support for such a thing into Qt, so IMHO
> this is the
> >>> first thing which must be implemented.
> >>>>
> >>>
> >>> The nime patch looks exactly same than Qt BorderImage (
> >>> http://developer.qt.nokia.com/doc/qt-4.8/qml-borderimage.html )
> >>>
> >>>
> >>> Also, system that uses different images for different states is
> >>> exactly same that is used on components
> >>> meegotouch-button-background-pressed.png
> >>> meegotouch-button-background.png
> >>> meegotouch-button-background-selected.png
> >>> ....
> >>> and this for all combinations, inverted, disabled ...
> >>>
> >>> The problem then comes more than could we do some mapping of Android
> >>> and MeeGotouch states like
> >>> meegotouch-button-background -> buttonStyle_View-background_Enabled.png
> >>>
> >>> MeeGocomponents uses mthemedaemon plugin that fetch images, so, if we
> >>> could make just mapping names
> >>> and json query, we could in theory get theme engine.
> >>>
> >>> Symbian components uses svg images , meegocomponents borderimages .
> >>> There is very little
> >>> difference in component API's. Least what I have used, porting on apps
> >>> were mostly changing import statements
> >>> and change of some colors.
> >>>
> >>> Kate
> >>>
> >>>>  This weekend I hope to have enough time to create a wiki page which
> will
> >>> describe the content of the json file.
> >>>>
> >>>>  Cheers,
> >>>>  BogDan.
> >>>>
> >>>>
> >>>>  [1] https://github.com/ereilin/qt-json
> >>>>  [2]
> >>>
> http://www.java2s.com/Open-Source/Android/android-core/platform-frameworks-base/android/widget/Button.java.htm
> >>>>  [3]
> >>>
> http://www.java2s.com/Open-Source/Android/android-core/platform-frameworks-base/android/widget/TextView.java.htm
> >>>>  [4]
> >>>
> http://www.java2s.com/Open-Source/Android/android-core/platform-frameworks-base/android/view/View.java.htm
> >>>>  [5]
> http://developer.android.com/reference/android/graphics/NinePatch.html
> >>>>
> >>>>  [6]
> >>>
> http://developer.android.com/guide/topics/graphics/2d-graphics.html#nine-patch
> >>>>
> >>>>
> >>>>>
> >>>>>  Hi,
> >>>>>
> >>>>>     Yes, sadly we have to get our hands  very dirty.
> >>>>>     First step is to identify all Qt components then we have to find
> >>>>>  Android's corresponding components, then we must extract the style
> >>> &
> >>>>>  look information to a central location (IMHO Ministro should do this
> >>> job), then
> >>>>>  any application which starts will peek this infos from that location
> >>> and use
> >>>>>  them to paint all controls.
> >>>>>     Second step is to check how Android paints the controls, here the
> >>> things will
> >>>>>  become dirty, we have to check
> >>>>>  "frameworks/base/core/java/android/widget/TextView.java" from
> >>> Android
> >>>>>  source code and it seems we have to use a lot of private data, I
> hope
> >>> the
> >>>>>  Android versions are not so different.
> >>>>>    Third step is to change Ministro in order to extract all the
> infos we
> >>> need to
> >>>>>  paint our controls.
> >>>>>     Fourth step is to create a QStyle plugin (which will be used by
> QML
> >>> as well)
> >>>>>  which loads the data extracted by Ministro and use it to paint the
> >>> controls. If
> >>>>>  the extract procedure is very fast (less than 10ms), I doubt it
> will be
> >>> that
> >>>>>  fast :),  we can skip the third step and extract the data directly
> in
> >>> QStyle.
> >>>>>     Fifth step, if everything works, we must get drunk !
> >>>>>
> >>>>>
> >>>>>  Cheers,
> >>>>>  BogDan.
> >>>>>
> >>>>>
> >>>>>>
> >>>>>>
> >>>>>>  While I don't agree on "almost all applications have the
> >>> same
> >>>>>  look" (as far as I can see, the only fully common UI element is
> >>> the
> >>>>>  menu/toolbar combo), I respect your choice.
> >>>>>>
> >>>>>>  The first step would be to define what is the "Android
> >>> style". Is
> >>>>>  there some Google guidelines you plan to follow?
> >>>>>>
> >>>>>>  Regards
> >>>>>>  - Chris -
> >>>>>>
> >>>>>>
> >>>>>>  On Tue, Jan 3, 2012 at 17:45, BogDan <bog_dan_ro at yahoo.com>
> >>> wrote:
> >>>>>>
> >>>>>>  Hi,
> >>>>>>>
> >>>>>>>
> >>>>>>>    I think none of your examples are good to follow :) The
> >>> reason why
> >>>>>  meego doesn't use QtStyle to draw the widgets is because meego
> >>> doesn't
> >>>>>  have a "native" style. Symbian is even worst, open any two
> >>>>>  applications on symbian and you'll see that none of them have the
> >>> same look
> >>>>>  & style :) On Android is a different story, almost all applications
> >>> have the
> >>>>>  same look & style, so if we want to have a first class citizen
> >>> port, all Qt
> >>>>>  applications *MUST* look the same as any android application. I'm
> >>> choosing
> >>>>>  to make QStyle plugin because this way all Qt applications will
> benefit
> >>> from it,
> >>>>>  either they are made using old-fashion widgets or QML components.
> >>>>>>>  For me a good android style is a top priority, I don't
> >>> believe
> >>>>>  I'll have enough time to finish it till beta 1 but who knows ...:)
> >>> maybe if
> >>>>>  other people will join me we can split the work and we can have this
> >>> feature in
> >>>>>  time for beta1.
> >>>>>>>
> >>>>>>>
> >>>>>>>  Cheers,
> >>>>>>>  BogDan.
> >>>>>>>
> >>>>>>>
> >>>>>>>
> >>>>>>>>
> >>>>>>>>  and please note that the Qt quick components (either
> >>> symbian or
> >>>>>  meego) don't use Qt widget styles. All the components are drawn in
> >>> qml so
> >>>>>  the componenets would unfortunately not benefit from your work on a
> >>> widget
> >>>>>  style.
> >>>>>>>>>  - Chris -
> >>>>>>>
> >>>>>>>>
> >>>>>>>>
> >>>>>>>>  On Thu, Dec 22, 2011 at 21:53, BogDan
> >>> <bog_dan_ro at yahoo.com>
> >>>>>  wrote:
> >>>>>>>>
> >>>>>>>>
> >>>>>>>>>
> >>>>>>>>>  Hi Chris,
> >>>>>>>>>
> >>>>>>>>>  Please accept my apologize for the slow reply.
> >>>>>>>>>  I think before we'll integrate the components into
> >>> Ministro,
> >>>>>  we must do a few things:
> >>>>>>>>>   - the components MUST use Android's style, next
> >>> year
> >>>>>  I'm planning to create a style plugin for
> >>>>>>>>>
> >>>>>>>>>  widgets which should be used by Qt Quick Components for
> >>> Android.
> >>>>>>>>>   - wait until Nokia finishes to define the API for Qt
> >>> Quick
> >>>>>  components [1]. We can't afford to break the API after we release
> >>> it :)
> >>>>>>>>>
> >>>>>>>>>
> >>>>>>>>>  Cheers,
> >>>>>>>>>  BogDan.
> >>>>>>>>>
> >>>>>>>>>
> >>>>>>>>>  [1]
> >>> https://bugreports.qt.nokia.com/browse/QTCOMPONENTS-200
> >>>>>>>>>
> >>>>>>>>>
> >>>>>>>>>>
> >>>>>>>>>>  Hi guys,
> >>>>>>>>>>
> >>>>>>>>>>  What would the steps be to integrate the Qt quick
> >>> components
> >>>>>  for Android to Ministro as a package?
> >>>>>>>>>>
> >>>>>>>>>>  - Chris -
> >>>>>>>>>
> >>>>>>>>
> >>>>>>>>
> >>>>>>>>
> >>>>>>>
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>  _______________________________________________
> >>>>>  Necessitas-devel mailing list
> >>>>>  Necessitas-devel at kde.org
> >>>>>  https://mail.kde.org/mailman/listinfo/necessitas-devel
> >>>>>
> >>>
> >>
> >
> >
> >
>
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