SetVisible(false) with the space occupied - java

I would hide a JButton in a JApplet. I'm using setVisible() method but I've a problem: it works but my GUI is shifted because of the absence of the component. Is there a way to hide a component and make its space occupied???
I know that is possible in Android, but in Java?
ps. To insert component in my JPanel I'm using GridBagLayout!

There are several ways to achieve this in general.
Most proper way is to layout other components in a way that they remain correctly attached at their current positions.
Since for complex layouts the proper way can be hard to get and especially hard to change afterwards, you can apply some layout 'hacks'. For example, instead of adding the button to the panel directly, you could add the button to a separate panel of its own (let's name it buttonPanel), and then add that panel together with the button to the panel containing the other components. That way when you remove the button, buttonPanel will stay to fill the gap.
However, depending on the way how you specified constraints, buttonPanel may shrink when you remove the button. To prevent this, just before removing the button, take the buttonPanel's width and set it as its minimum/preferred width; most LayoutManagers will respect this property.
Of course, you can always resort to hardcoding dimensions to avoid dynamic size calculations, but keep in mind issues with L&F and i18n.

Try using the setOpaque() method. Just do button.setOpaque(false); and that should do the trick. Does that work?

Related

Auto scaling components with Java JFrame [duplicate]

Not sure if what I need is possible.
I have a container (JPanel) that contains some internal elements.
I was wondering if it is possible to force internal elements to fit into the container's size.
I need them to be fully visible i.e., resize to fit inside the Panel's size and not cut some parts of the internal elements.
Scrolling is not an option.
Is this possible by using a Layout or something?
EDIT: Important clarification:
The thing is that I do not have access to the internal elements neither to their properties so I would say that a Layoutmanager capable of resizing child elements to fit to its size is needed. I tested BorderLayout and GridBagLayout but the result is always the same, the internal elements are cut out.
It's for exactly that reason that LayoutManagers exist. All the LayoutManagers work for simple containers directly, excluding GridBagLayout which is to able to handle most complete GUIs directly.
For most complete GUI's you have some choices as follows:
Look for a 3rd party layout such as MigLayout or here
Use GridBagLayout
Very easy way is use nested layout, where there is more than one JPanel and each has child JPanels with the same or different LayoutManager
Or custom layout, should be hard..., but same as using GridBagLayout
You could set the JPanel layout to border layout, then add the single child to the center. If there are multiple children, this approach becomes less useful since components added to the the NORTH, SOUTH, EAST, and WEST will remain statically sized while the centre resizes to fill the remainder.
In short, this isn't an ideal solution. All layouting in Swing is made all the more complex by the fact that different components behave in different ways, so you really need to provide further details of the child components you wish to add to your panel, and any behaviour that has been overridden on those components.
The best way is to try a couple of simple examples to see what mileage you get and whether subtle redesign of your child component nesting could help.
you can use a layout, like GridBagLayout, or BorderLayout depending on the situation. With proper weights it is possible.
this sounds to me like you should just peek an appropriate layout manager and use it. For example, look at BorderLayout - put your component in the CENTER and it will occupy all the area. Its up to each concrete layout manager to decide what will be the size of the components.
Mark
I was using a JInternalFrame inside JDesktopPane. I wanted the internal_frame to auto resize as desktop pane is resized, so I had to implement the AncestorResized event for the internal frame where I placed the following code:
this.setPreferredSize(this.getParent().getPreferredSize());
this.pack();

A Flexible Layout manager that will change the layout according to resize

In my JPanel, I have 6 buttons laid out in a row (using FlowLayout as of now). The default size of the panel is enough to accommodate these buttons in one row. But, when the frame is resized it gets stuck at the size that is the sum of the minimum sizes of each button.
I need a layout manager that simply puts the buttons in a new row on re-sizing of the panel.
I'm pretty new to Java Swing so I apologize in advance if this is a trivial question.
MigLayout is by far the best layout manager I've ever used. Things that used to require nested containers and lots of hard to understand code can be done in a single container with simple to understand (and maintain) string constraints.
The flow layout is capable of your desired behavior (moving components into new row if they cannot fit). Check out the swing tutorial (run FlowLayoutDemo). You'll have to show us your source code to find out, whether there is some other constrain which prevents it.
FlowLayout does actually paint components on a new row, but the problem is that the preferred size of the panel doesn't change so in many cases you can't see the components (unless you happen to add the panel to the CENTER of a BorderLayout).
One solution is to use the Wrap Layout, which extends FlowLayout to recalculate the preferred size of the panel so that you see the buttons on a new row.

How to hide other panels or panes during coding

Using Eclipse Juno for Java & WindowBuilder
I have three panels of the same size that lay on top of each other - they have different widgets. During coding, they all display and clutter up what I'm doing.
I can show and hide them in runtime as needed but, I want to display only the one I'm working on while doing drag and drop of widgets. I've tried using different panels and pane types (tabbed, layered...) and selecting opaque but, nothing hides them.
How do I hide the other (panes, panels...etc) during coding?
I have the same issue. Among other reasons, my solution was to create separate classes per view. So my frame would be its own class, it would maybe have a TabbedPanel (or whatever it's called), and then I would have a new class for each tab on that tabbed panel. Each class would extend JPanel so I could plop it right in there. That way not only is your gui design not cluttered up, but your code logic is separated into separate files, where it might belong anyway.
[SOLVED] Answering my own question.
It may not be perfect or the best/correct way, but it works!
WindowBuilder wants to Surround other panels/widgets that are within it's bounds so, you have to trick it by using opaque, Order>forward/backward then setting the desired bounds (all panel sizes and bounds can be equal and will overlay nicely both during widget drag&drop and runtime).
Here's how to do it with a 3-Panel example (NOTE: WindowBuilder is buggy/in-consistent and often I needed to select the items from the gui, not in the Components tree).
Create your first panel. Add your widgets and border to it.
Create your second panel (the one you want to overlay on top of the first one). This second panel MUST not be completely inside the first panel - it MUST extend beyond the edges of the first panel (parts of it can be inside the first panel). This takes a bit of trial because of the 'surround', mentioned above. Use the shift-key to stop the snapping.
Select the top panel in the gui, NOT from the Components tree, and toggle the Opaque property. The top panel (first or second) in the tree is the one you set to opaque and work on.
Add another panel and repeat the process.
Once you get your widgets/etc as you want them, use the property Bounds to set them all the same or as desired. After that, as long as you don't move a panel by dragging it, it will remain un-surrounded by the other panels. If you move by dragging, it may get set to surround...
I've done this a dozen times now and it works consistently.
Below is a shot of 3 panels overlayed, un-surrounded and not opaque, thus showing widget clutter
Below is a shot after the bounds are set (and not surounded). Opaque and order not yet set:
Below is a shot with bounds set and panel 3 moved forward and opaque set:
Below is a shot with bounds set and panel 2 moved forward and opaque set:
... etc, etc... Now you can work on a panel that's ordered to the front and, naturally, use the setVisible in your code...

How to set JPanel size?

I'm using Netbean's form creator and I'm trying out some things. I'm not sure if it's the layout manager, but when I create my own JPanel and add it to the main content pane of the my window, the size of the panel always maximizes inside the FrameView no matter what re-dimensioning methodology I use such as setSize or setPreferred size. I'm very new to AWT and Swing.
With NetBeans WYSIWYG designer it's a peace of cake - just be sure to use Free Form Design and use mouse for resizing. Maybe the panel is itself larger than FrameView, so double click on it (you are editing it exclusively) and make it smaller. Than double click to get back to parent component and you should be fine.
Or maybe check some tutorials at NetBeans site.
You're not supposed to set sizes manually. Leave that to the layout managers, and your GUI will not break when the window size or the font or even just a button label changes.
The trick with layout managers is that you can use not just one but several, in nested JPanels. That way, nearly any layout is possible.
This happens because the layout manager of JPanel's container (perhaps it is either JFrame or another JPanel) instructs the JPanel to maximize.
Do the following:
Find out, who is the parent of this JPanel (take a look at NetBeans's containment object tree)
Check, what layout is defined for the container
Read the documentation about LayoutManager's (they're in java.awt package)
???
PROFIT!
In my experience, Swing is a very picky thing. I'd try setMaximumSize and setPreferedSize. As a side note though: when ever I used GridLayout, it always stretches whatever is in each of the cells (to make it symmetrical I guess). Flow, Box, Border, and I think GridBag don't have that problem though.
-Brett

Change button text without changing button size

I'm using a borderLayout to arrange my components in a JFrame and a Box(BoxLayout.X_AXIS) to put buttons next to each other. But it creates two problems:
I want the buttons to have the same size, but it automatically resizes them to fit the text within them (especially annoying when I change the text inside a button at runtime)
I want the buttons to have a little bit of space between them (let's say 10 px)
Is this possible using the borderLayout, or do I need to use the setLayout to null? And if so, wouldn't this screw up the original placement of the buttons in the frame? Or would this still be dealt with by the Box which is placed with the borderLayout?
A couple of suggestions
Try setting the preferredSize to a suitable Dimension value
If that doesn't work, try also setting the maximumSize and minimumSize to this same Dimension value
If that still doesn't work, change the buttons' layout manager to a GridBagLayout. The advantage of this layout manager is that it lets you control the layout's behaviour in minute detail. The disadvantage is that you usually need to configure a large number of properties on the GridBagLayout in order to get the desired behaviour. I'd advise checking out a GridBagLayout tutorial first, as it's a reasonably complex beast.
If you want them to have the same size then just add the buttons to a GridLayout and they will automatically be sized to the largest text string. You can also specify a gap between components.

Categories

Resources