I've created a GridBagLayout with a JScrollPane(JTextArea) in the first row (spanning 3 columns) and 15 JButtons in the other 5 rows (each button spans 1 column).
I have set the weights so that all of the components expand equally as the window is resized, and the frame minimum size to its preferred size. However, I'd like the height of the JScrollPane to be 5 * the height of each JButton (half of the total frame height). Is there a simple way to enforce this?
However, I'd like the height of the JScrollPane to be 5 * the height of each JButton (half of the total frame height). Is there a simple way to enforce this?
If you want the area to be half the height then use a different layout manager.
Create a JPanel that uses a GridLayout. This way each component will be the same size.
Then add the scrollpane to the panel. Then create a second panel that also uses a GridLayout. Add the buttons to this panel and then add this panel to the main panel.
The bottom line is you can use multiple panels each with different layout managers to achieve your desired result.
Related
I am attempting to code a JFrame containing a JPanel. Within the JPanel is an array of JTextField's. So, my GUI looks like:-
I am not using a layout manager, and have set this to null for the JFrame and the JPanel. I am sizing these components by hand.
You can see that the right hand portion of the JPanel is chopped off, even though I have used the same sizing as the containing JFrame.
The code appears as below:-
I have calculated the required width of the JPanel by multiplying the number of columns in the JTextField array by the width of the JTextField. Aside from that would need to be added the width of each gap between the JTextFields (there would be (columnNumber - 1) of them), as well as the two border gaps.
I have done this, yet the right hand side border gap is chopped off, as you can see from the diagram.
If I add some random amount to the panelWidth, then you can see the right hand gap there, but my question is what am I missing here? This ought to work surely, if the JFrame side and the JPanel size are identical, which they are as I have also printed them both out, and the print outs give the same number.
Jeremy
I want for any combination of row/column values to allow a constant vertical & horizontal distance between each JTextField, and for each of those text fields to maintain default sizing.
The GridLayout allows you to specify a horizontal/vertical gap between each component and allows you to control the size of the grid.
Then you can wrap the panel using a GridLayout in a panel that respects the size of the grid.
For example you could do:
JPanel grid = new JPanel( new GridLayout(...) );
JPanel wrapper = new JPanel( new GridBagLayout() );
wrapper.add(grid, new GridBagConstraints());
frame.add(wrapper, BorderLayout.CENTER);
If you pack the frame, the grid panel will be displayed at is preferred size.
If you resize the frame the grid panel will remain centered in the wrapper panel.
The top part of that GUI is well suited to a grid layout, the bottom part with 'Go / Cancel' buttons - a flow layout. Put the grid layout in the CENTER of a border layout, the flow layout in the PAGE_END, pack the top level container (for non-cropped, 'right size') & the job is done.
It might end up looking something like this:
I have a JScrollPane whose viewport is a JPanel. The JPanel contains smaller JPanels that take up the entire viewport's width, and the big JPanel is set to a FlowLayout. The user should be able to add as many JPanels as they want (well, up to 200 for my purposes), and they should be able to scroll down the JScrollPane to see everything they have added. Basically I'm just trying to make the JScrollPane grow. I'm calculating what I thought the JPanel's height should be like this:
Dimension dimension = new Dimension(width, smallPanel.height * totalPanels
+ ((FlowLayout) getLayout()).getVGap * totalPanels);
setPreferredSize(dimension);
And it mostly works, but as you add more, it starts cutting the smaller JPanels off, and the bottom panel eventually isn't shown. Is there a way that I can determine the size of the JPanel for the viewport so that I wouldn't have to calculate its dimensions with variables? Like pack() does for JFrame? Or do I need to keep guessing and checking?
Thanks
I've two JPanels inside a JFrame but when one JPanel is bigger in height that other then it is being automatically aligned vertically center.I'm using GridBagLayout.Why is that though I set weighty=0? What should I do for aligning Panel1 to top whether Panel2 is bigger or smaller? Thanks.
GridBagLayout is honouring the preferred size of the components.
If you would like the components to have the same height, you can use the fill property of GridBagConstraints and set it to GridBagConstraints.HORIZONTAL, which will tell GridBagLayout to fill all the component within the given row so that they meet the height of the row (which should be the height of highest component in the row)
If you just wish to align the components (to the top), you should change the anchor property to GridBagConstraints.NORTH
See How to use GridBagLayout for more details
I have a List<JToggleButton> and I need to add all those buttons to a panel.
The panel needs to have only a vertical scrollbar. It has a fixed size of 600 x 600 px.
Buttons have different sizes and I need them look pretty compact (for example, some rows can have two big buttons, some four smaller). I need to add the buttons by order from list (first with index 0, then 1 and so on..).
How to achieve this layout?
You can try placing the JPanel with a FlowLayout in a JScrollPane and add all the buttons.
I have created n JPanels and in each JPanel I have added 3 components. I added these JPanels to a new JPanel as rows. The layout for the n JPanels is FlowLayout and for the main panel is BorderLayout. The setPrefferedSize() method is working fine for the components which I have added in the n JPanels but it is not working for the n JPanels.
I am trying npanels[i].setPrefferedSize(new Dimension(300,25)),
I want the height of the JPanel to be equal to height the components added in it (which is 25).
Is there any constraint that the height of a JPanel should be some minimum value?
Please help I tried a lot of things but it's not working.....
Some layout managers tend to ignore the size setting...
Read somewhere that BorderLayout might tend to ignore the width for NORTH and SOUTH components,
height for EAST and WEST,
both height and width are ignored for CENTER...
Could this be the case?
Also, can you provide a screenshot or a diagram explaining whats happening?
The setPrefferedSize() method is
working fine for the components
There is generally no need to set a preferred size for components. Swing will calculate the preferred size automatically.
layout for n JPanels is FlowLayout...
which i have added in n JPanels but it
is not working for n JPanels
Again, there is no need to set the preferred size of each panel. The size will be calculated automatically based on the preferred size of all the components.
the main panel is BorderLayout
This does not make sense since you can't add "n" panels to the BorderLayout. You can only add one component to the North,Center and South so you can have a maximum of 3 different vertically display panels. In this case if you use frame.pack() then each panel will be displayed at its preferred size. On the other hand if you use frame.setSize(300, 400) then the hieght of the Center panel will be stretched.
Since it appears you want all panels the same size maybe you should be using a GridLayout, otherwise you can try a BoxLayout. Read the Swing tutorial. It explains all about using the layout managers.
If you need more help post your SSCCE.