Is it possible to drag a JLabel from one panel to another?
I can only drag the label within one panel. When the label moves out of the burden, it just disappear. I don't know what to do.
You can easily do this in several ways. One way is to
bump the label to the glass pane on mousePressed(...)
drag it in the glass pane on mouseDragged(...),
then drop it down to whatever container the mouse is currently over on mouseReleased(...).
You will have to remove the label from its current container when you start dragging it. Normally we add it to the glass pane to allow for the illusion of been dragged across multiple components.
Take a look at My drag is better then yours for an example. I'd also recommend that you have a dig around his site, he does some nice work with drag and drop
Related
I need to give the user of a UI the option to switch between two border panes on clicking a button (or toggle switch or whatever).
The panes have the same job, size and position - it's just a different configuration so I don't want both of them there at the same time.
When designing the UI in SceneBuilder I cannot place them at them same spot and set one visible and one invisible - because SceneBuilder obviously doesn't know that I want to stack them on top of each other.
Is there a way I can include both of them in the UI but only show one at a time?
I'd appreciate any ideas :)!
What you are looking for is the CardLayout. See oracle's documentation on that: https://docs.oracle.com/javase/tutorial/uiswing/layout/card.html
Instead of adding your Components directly to the Component with the BorderLayout, instead add a JPanel which is using the CardLayout. Add the two Components to this JPanel.
Unfortunately I have no way to test this with the SceneBuilder right now, but you'll figgure out, how that works ;)
I'm pretty new to programming Java based GUI applications. Here's what I have in mind, I want to divide the window into two areas.
The first are contains buttons (or a list), and based on which button was clicked, or which item was selected, the second area changes. (finite number of buttons)
Something like this:
I can think of many ways to do this, but I am not sure what is the best practice. Do I have several invisible panels and make only 1 panel visible at a time, or do I change the ordering (bring panel x to front), or is there some other way?
Appreciate any help I receive!! Thanks in advance!
Although this is a primarily opinion-based answer I'd go with a Nested Layout approach:
Main panel with BorderLayout. Or you can use the frame's content pane which already has BorderLayout as default layout manager.
Left panel with BoxLayout (or GridBagLayout).
Right panel with CardLayout.
Note: Buttons in the left panel should switch right panels cards.
See Lesson: Layoing Out Components within a Container tutorial.
For complex GUIs you have also third-party layout managers available, listed in this answer:
MiG Layout
DesignGridLayout
FormLayout
Building a Java GUI application using Netbeans IDE. I have created a JPanel in it. After adding a lot of fields, I want to also add a JscrollPane to it. I have found that if we right click on the pane we have an option to Enclose it in a container that can be Scroll pane or Split pane etc.
The problem is, that the enclosed button is greyed out when I right click on the panel. How should i fix this ?
I had the same issue. After experimentation, it appears you can only use Enclose In if the Layout is set to Free Design.
However, an alternative method I discovered to accomplish the same thing is to create the empty JPanel and the components you want inside it, all at the same level in the TopComponent. Then drag and drop the components you want into the JPanel, using the Navigator window that shows the component hierarchy.
For example, here I've created a JPanel and a JRadioButton as siblings, and then I drag and drop the JRadioButton inside the JPanel, so that the JPanel is the parent.
Result:
I have 3 image so I want, if I drag any image that should appear above all the other images. Which technique can use? please any idea???? By the way I am using "ImageIcon".
Thanks in advance.
If what you want to do is click on an image, lift it above the others and then drag it, consider placing them in ImageIcons and these in JLabels, and displaying them in a JLayeredPane, or a JPanel that is held in a JLayeredPane. You can then lift the clicked label onto the JLayeredPane.DRAG_LAYER while dragging, and then drop it down into the DEFAULT_LAYER (or on a JPanel that's on the DEFAULT_LAYER) when done. For an example of this, please see my code in a related question: dragging a jlabel around the screen
If I'm totally off base, sorry, but please correct my incorrect assumptions.
By the way I am using "ImageIcon".
I assume this means you are adding in image to a JLabel and are then adding the JLabel to a JPanel.
so I want, if I drag any image that should appear above all the other images
You need to add a MouseListener to the JLabel. When you click on the label then you can reset its Z-Order to 0. This will cause the label to be painted last and so it will be on top of all other labels on the panel.
So the basic code in the MouseListener would be:
panel.setComponentZOrder(label, 0);
In short, my need is to have a background Image in my java app, and upon some event, create some other graphics on top of that image.
I was thinking I would use a JPanel to draw the background image in, add it at to my JFrame the start of program, and then add other JPanels on top of that upon certain events. The problem is Swing gives the JPanels added first the highest Z index, so what should be my background is showing up on top of everything.
Is there any way to control the Z index/order of the JPanels, or am I going about this completely wrong?
You can use the setComponentZOrder() to handle Z-Order in your application.
Resources :
JavaDoc - Container.setComponentZOrder
oracle.com - Mixing heavy and light components
Sounds strange to add mutiple JPanels and use z-order. I would suggest you either simple add ONE JPanel with the paintComponent(Graphics g) method overwritten, where you draw the correct image according to your events.
Or use the CardLayout, and add JLabels (with different images), then when your event triggers, use
CardLayout cl = (CardLayout)getLayout();
cl.show(this, "card3");
to show the correct JLabel.
The JLayeredPane is designed for just this purpose. It allows you to control the Z-order of components.
I was thinking I would use a JPanel to
draw the background image in, add it
at to my JFrame the start of program,
Sounds reasonable.
and then add other JPanels on top of
that upon certain events. The problem
is Swing gives the JPanels added first
the highest Z index, so what should be
my background is showing up on top of
everything.
Adding a panel to a panel is just like adding another component to the panel. The child component will be painted on top of the parent panel. There is no need to play around with Z-Order.
The key is to set a layout manager on the panel with the image. Then each panel you add to the image panel must be made non-opaque so that the background image will be painted.
Maybe the Background Panel can help you out. It automatically makes any component added directly to the panel non-opaque.