I'm using Qt Quick 5.13 for several projects, some of them require a data grid with a column header, handling advanced functionalities, among others allowing the user to resize the columns, sort their content, or swap them.
Between the Qt Quick available components, the most suitable for my needs is the TableView component. However, there is some vagueness as to what it really supports. First of all, it seems that 2 versions of this component exist: one for the controls 1.0 and one for the controls 2.0.
Obviously the version belonging to the controls 2.0 is the most interesting for me, because I know the limitations of the controls 1.0 (performance leaks, no high DPI support, ...). However the TableView 2.0 has a serious issue: it no longer provides any kind of TableViewColumn component. In other words, the only way to show a header above my data grid seems to be to have to write it myself, which is a painful work.
For that reason, I wonder if I will still use the version 1.0, despite of its limitations. However several points are unclear for me. For that reason I have the following questions:
Will the controls 1.0, especially the TableView and the TableViewColumn ones, be tagged as obsolete in a near future, and eventually removed from Qt Quick?
Is a such TableViewColumn planned in a near future for the TableView 2.0 component?
As the high DPI support is important for my projects, is it easy to workaround this issue with the TableView 1.0 component?
Is there another component like e.g GridView, ListView, ... which already contains a ready-to-use header? If yes, which component should I use instead of the TableView one? Or what is the better choice for my situation, and why?
Which solution is commonly selected by the developers when they face a such situation?
Related
wisgetwas wondering what widget in gtk (using gtkmm) could be used to implemented the movable button looking thing in the picture. and also the dotted line.
dotted line
edit: the widget is supposed to be able to move left and right along the time-track to be able to set the play bounds. Here is a video showing how it looks like in after effects. From sescond 37 is how the behaviour for it supposed to be. https://www.youtube.com/watch?v=QxXevteeumg
edit: from what it looks like there isnt a specific widget which could simplify this. However a regular button can be used and then implementing a method for its drage using the various signal handlers associated with a Gtk button
There is no widget that does this (see the widget gallery).
You can, however, add custom widgets using Cairo. In the official Gtkmm book, there is an example for creating a custom clock widget using the Gtk::DrawingArea. The Gtk::DrawingArea offers a lot of signals which you can connect to.
I have created my own widgets in the past using this and it worked just fine. However, it was a lot of work because:
Cairo lacks good documentation. Understanding the philosophy behind this library is a lot of work, often empirical.
It can be hard to acheive acceptable performance using Cairo. One has to be really careful in how the drawing of the widget is performed. There is often a naive way to do it, which is clearer in the code, but devastating in terms of performance (it often involves useless redraws on the CPU).
I have a lot of FlexLayout element in my template and it is so slow on iOS devices.
i replaced that with StackLayout and now it became little fast than before.
I'd like to know which Layout Container is fastest layout in Nativescript.
There is never one right solution for all various needs, which is why we always have options and that applies to layouts in {N} too.
Learn more about layouts interactively at nslayouts.com and choose the one that suits your use case.
If you show use what exactly you are trying to achieve, we may able to give you some suggestion. There are some general guidelines you may have to follow for better performance,
Avoid nested layouts
Use GridLayout when you need known number of partitions in your UI, the less the number of partitions are, the better the performance would be. Use FlexboxLayout otherwise.
If you just want to stack items in vertical or horizontal order, StackLayout may be a good option. Use FlexboxLayout only when you want to use flex box specific features, like when items has to be wrapped to next line, change order of items etc.,
Try to not use StackLayouts just for the shake of borders around, since you can add border to the component itself.
If you have really complicated heavy UI components, you may load it once the page has completed navigation, that may be faster.
Prefer ListView over Repeater / for loop as much as possible.
By following the above at least I can confirm, I don't hit performance issues in my apps where I have 100s of elements and 10s of partitions on screen. If you still face issues, try creating a Playground example where we can see the issue.
I noticed this same thing with FlexboxLayouts on IOS where I was doing animations with the layouts. It worked great on Android, but was very slow on IOS. I switched it to a GridLayout, and things worked a lot better.
I've continued my journey with Singularity, and I'm enjoying experimenting with this framework. I've created an experimental site at Sassmonster.com (Github repository here at https://github.com/58bits/sassmonster).
I was discussing this framework, along with other 'semantic' frameworks (if that's the right term in this case) vs presentational markup frameworks like Foundation, and Bootstrap.
I was wondering if anyone could summarize the relative merits of the approach that Singularity (and the original Semantic Grid) takes - without requiring grid classes or attributes to be present in markup.
The main advantage, if I've understood this correctly, is the ability to dynamically change layouts independent of document source order or any fixed class attributes (e.g. new grid layouts and grid span settings at given breakpoints, including source order independent changes like a sidebar switching from the left to right sides).
I'm sure there are others but would be grateful for a summary from someone with more experience than I have ;-)
Lastly - in terms of the future of grid systems in general - will the general adoption of the CSS Grid Layout Module obsolete frameworks like Singularity?
The advantage to semantic frameworks is that they take abstraction a level deeper than class names. This gives you, the author, the flexibility to generate your own list of classes like Bootstrap or Foundation OR you can apply grid styles to any element without being restricted by classes. Classes are flat and inflexible but having logic abstracted to mixins provides significantly more flexibility.
The advantages you address have more to do with the output model. Singularitys default output mode is called isolation and you can read about how it works here: http://www.palantir.net/blog/responsive-design-s-dirty-little-secret. With singularity you can use old fashioned floats or even write modules for CSS grid layout if you want. Singularity was designed to be future-proof and provide a common framework to do many different things with grids.
Lastly, yes, grid layout does some really awesome stuff and I hope it makes Singularity and other grid systems obsolete. However the syntax and conventions of grid layout is not so great and you may want to abstract some of it out. Some of the conventions are similar to that of Singularity like ratio based column math so that is pretty cool.
I'm developing my first Android game and I'm having a bit of difficulty making the UI as smooth as I would like. I've spent a couple of hours googling around with no luck, I'm probably just searching for the wrong thing.
I have two different XML layout resources where each layout contains just one SurfaceView subclass. When I call activity.setContentView(R.layout.second_layout) to transition from the first layout to the second layout there is a noticeable period of time where a black screen (with a small white bar along the top) is displayed in between the two views.
I've tried various things such as; constructing the second view manually at runtime (i.e not using a layout XML file), calling activity.overridePendingTransition(android.R.anim.fade_in, android.R.anim.fade_out) after activity.setContentView(R.layout.second_layout) and attempting to render to the canvas before the view has loaded (turns out the canvas is unavailable).
I don't see other games (or apps) having this issue so I presume there is a reasonably simple solution.
If you need some more information about my particular situation in order to help out then please let me know what information is missing. Any help would be largely appreciated.
Update: My answer below was written in 2010. Since then Fragments have become the norm, particularly since Fragment nesting was made possible and the support library allows this functionality to be used in a backwards compatible fashion. As such, instead of transitioning to a new Activity to perform a new "user task", you can use the one Activity and push and pop fragments within that Activity's view hierarchy. Animations can also be performed as a part of a fragment transaction (e.g. Fragment transaction animation: slide in and slide out).
This became pretty apparent not long after posting this question, however I thought I should come back here and make it clear to everyone else.
Activities are positively the way to go when developing for Android. Don't be put off by the fact that a transition may seem too minor for a separate Activity, the very foundation of Android is built around the idea of an Activity.
I've been working exclusively with ComponentArt controls and want to know what else is out there. What Grid and Treeview controls are worth investigating?
It doesn't matter if I need to pay for them... quality, speed, and reliability are key.
I've seen a few issues with the CA Grid Control has issues with setting the column width dynamically, and documentation is spotty. However it has a single programming model with the SOA offering. Are there better options out there?
Try dhtmlx Grid and dhtmlx TreeGrid , although these are javascript components we have used them with asp.net and find them to be very fast and flexible.
jqGrid is a nice AJAX-enabled grid written in JavaScript that has worked out well for me in several recent projects.
jQuery treeView looks like a bare-bones treeview that may be worth investigating, although I have not used it on any projects so your mileage may vary.
I use the Telerik's AJAX/Silverlight grids for my web apps and I am pretty content with them. The components are flexible and designed with the idea of rich set of features without compromising the overall performance. If you want to have a look at their online examples, go here.
Dick