Develop Reference

UI not aligning

I am using LibGDX and Scene2D to create a simple menu for my game.
Here is a simple example that works for me:
table.add(gameLogo).row();
table.add(button1).row();
table.add(button2).row();
table.add(button3).row();
I didn't include the irrelevant code(including the table into the stage for example).
If I don't include .row() to each object that I add to the table, then the menu isn't aligning to the center, which is very odd, for example:
table.add(gameLogo).row();
table.add(button1);
table.add(button2).row();
table.add(button3);
Why is the menu behaving like that? should I use more tables or add some HorizontalGroups perhaps?
If you need any additional information, or images I can provide, although it does the same for even the simplest menu implemention possible with LibGDX and Scene2d.

This is a colspan problem.
Looking at your code, this is what you are currently doing :
I assume that you would like to display your menu like that :
In order to do that, as you can see, you need to set the colspan size of your gamelogo to 2, so that it will take as much size as 2 regular cells.
So, to achieve this result, your code should be :
table.add(gameLogo).colspan(2).center().row();
table.add(button1);
table.add(button2).row();
table.add(button3);
The align(Align.center) or center() methods will not work alone, since these methods are only used to align the widget inside it's own cell.
If you experience more problems with libgdx ui table, remember that you can enable a debug renderer to display the cells border :
table.setDebug(true);

GWT Celltable fixed columns

Is there a way to make, let say first 3 out of 7, columns fixed in Cell table. I want to be able to see always first three columns and have horizontal scroll on others.

You will have to create a custom widget that consists of a ScrollPanel, which includes two CellTable widgets set side by side. The right table should be wrapped in a FlowPanel with overflow-x property set to AUTO (overflow-y should remain at HIDDEN).
You can use the same DataProvider for both tables to synchronize all changes. Be careful with the SelectionModel though, if you need it. I would limit selection to the first column of checkboxes and disable selection by clicking on a row.
Make sure that your widget fits into its space, or you may end up with two horizontal scrollbars - one for the ScrollPanel and one for the right table. Finally, remember to set sizes on both tables so that they have the same height.

Dynamic JList implementation

I have a list of entities where each entity render into widget based on JPanel. Widgets have dynamic behaviour - once placed on panel it can be changed by underlying entity. This happens automaticaly. Moreover some widgets can be resized by different actions, on button click for example.
The question is how to organise them into something like JList but without rubber stamp technics. In other words I wanna JList where each item rendered with cellrenderer stay "alive".
Right now I have implemented quick-and-dirty component based on JPanel with vertical BoxLayout, it uses JList's renderer component and it's model... but my implementation is too dirty...
Um.. yeah, using JTable is not suitable too.
Do you have some ideas?

If you don't want rubber stamping to take place then you'll have to create your own JList implementation that uses actual components.
You could try and work around the rubber stamping effect by caching each component for each row in your renderer and bind values into it and return that instance when JList asks the renderer for it. This is pretty risky because if you have 20 rows being displayed you'll have to cache 20 instances in your renderer, and only when the row isn't visible can you reuse one. That would mean if you had 5 unique configurations (A,B,C,D,E) of components you might have 10 of type A, 5 of type B, 2 of type C, and 3 of type D, and 0 of type E being displayed. However, you can't simply reuse one of those components without knowing if its being displayed or not. So you'd have to take into account if the row is being displayed and if it's the right type for the row you are rendering. And you'll have to clean up after the row is hidden.
Another option is make a single component for the row that encapsulates all X variations you have and put those on a CardLayout. Then you can simply cache one per row being displayed, and simply swap the card being displayed upon rendering that row. I think that might be the simplest option for you.
The harder part is going to be routing events click mouse clicks, keyboard events, etc to those active components to have them respond like normal components. Re-rendering the buttons when the user clicks them, and so forth is going to be challenging. Not impossible, but tedious.
Finally, variable row height JList is a pain. Especially in your calculations to figure out if a row is displayed or not because you can't simply do easy math like: int rowHeight = jlist.getHeight / model.size(). It doesn't work. You have to calculate each row's height and them up to figure out if a row is visible or not.
Doing what you're talking about is a lot of work, and very tricky coding to work around some of the assumptions of JList to make it work. In the end you might find it easier just to implement your own List control that makes different design decisions. Either way its going to require you are good at Swing to get it to work.

Ok. I don't find any implementation of such component. Let it be first one.
https://github.com/wertlex/JActiveList
P.S. I don't think this is proper way implementation... but it works.

use JList and ActionListener XD

Extended JTable clipping problem

Hi I'm using set of classes I found on internet that extends JTable capabilities making me able to merge or split some cells.
Mentioned capability works ok but I have two problems with how the table is displayed. The extended JTable is stored in JScrollPane and it is stored in Box.
The first issue is that when I have a lot of collumns the last one or last two ( depends on how many collumns I have ) is being clipped ( when I move scrollbar to the right edge I don't see last collumn or it is clipped so only the part of the data is visible.)
I did some experiments and I add some empty collumns and that helped so I assume it is something connected with how JScrollPane gets the width of the table it should display but I could not figure out how can I change that. I was trying to call table_.setPreferredScrollableViewportSize(new Dimension()); with Dimentsion set to something really big but it did not help.
Second issue is that when I click on a cell that is placed closer to the right edge then the next cell is being selected. The further the cell is from the left edge the further cell to its right is being selected. I can't see selection when I click on the cell from last collumn.

If there is no easy answer maybe someone knows some open source alternative to display data in table with merging capabilities. I found only commercial ones which cost a lot of money.

Make top row of GridView non-scrollable

I have a GridView of 9 rows of which the first one is sort of "header" row.
As there are 8 more rows they flow beyond the end of screen and need to be scrolled down to.
However this scrolling also causes the first row to go "off-screen".
Was wondering if there is any way I can prevent the first row alone from being scrolled off?
I dont want to make this a separate LinearLayout as it is part of a dynamic View (the GridView) that I create at runtime.
TIA

Was wondering if there is any way I
can prevent the first row alone from
being scrolled off?
Not that I am aware of, sorry.