Say I have a GridLayout in a JPanel, if my layout isn't big enought to fill the whole JPanel, it will auto align it at the center of ther JPanel like:
But I want my layout to align it on top left of the JPanel like:
so my component will start on top left of the panel, is there any method to do it?
Add your gridLayoutPanel to another panel i.e. subPanel. Set this subPanel layout to the flow layout like subPanel.setLayout(new FlowLayout(FlowLayout.LEFT)). Than set your main panel's layout to BorderLayout. And add your subPanel panel to the NORTH position of the main panel.
Example code:
JPanel subPanel = new JPanel(new FlowLayout(FlowLayout.LEFT));
subPanel.add(gridLayoutPanel);
mainPanel.setLayout(new BorderLayout());
mainPanel.add(subPanel, BorderLayout.NORTH);
it will auto align it at the center of ther JPanel like:
Sounds like you are using a GridBagLayout on the main panel and this is the default behaviour unless you use the GridBagConstraints to control this behaviour.
Read the section from the Swing tutorial on How to Use GridBagLayout, especially the section on using the weightx/y constraints. Setting these constraints correctly will prevent the panel from centering itself.
Related
Sorry if I might mix terms up. So I have a basic application where I would press the button and Jpanel1 with a label in it, would then switch/replace to JPanel2 that'll have a picture in it, all within the panel.
The JPanel inside the box would change from Jpanel1 to JPanel 2 after pressing the button. So is their a way to instance a JPanel in a panel or JFrame? I can't find the method on how to fill the panel with the JPanel.
frame.getContentPane().add(panel, /*layout.location*/);
You mean add
The exact way to do this depends on the LayoutManager you use. I suggest checking out the Visual Guide to LayoutManagers. For example, if you use a BorderLayout, you can add a panel to the center and then replace it with a different panel when the user clicks a button.
I ended using layeredPane with a card layout. Then I placed a panel using the center Border Layout, then instanced the JPanel as the panel from a different class.
Picture of Windowbuilder layout
panelPPBrowser = new JPanel();
layeredPane.add(panelPPBrowser, "name_216881785358769");
panelPPBrowser.setLayout(new BorderLayout(0, 0));
panelBrowser panelBrowserCon = new panelBrowser();
panelPPBrowser.add(panelBrowserCon, BorderLayout.CENTER);
I've got a BorderLayout going on, and am working on the North panel. Inside the North panel, I'd like to have 3 components: a picture that is on the left, and two buttons that split the remaining width of the Frame. Right now I'm attempting to accomplish this with another BorderLayout.
The Frame is resizable.
The picture is assigned to BorderLayout.WEST, and with the following code I attempt to add another panel that contains only buttons. The panel is then added to the CENTER of the Frame's NORTH layout component.
//create panel to hold buttons
JPanel btnPanel = new JPanel();
btnPanel.setLayout(new BorderLayout());
JButton btnMatrix = new JButton("Matrix View");
btnPanel.add(btnMatrix);
JButton btnList = new JButton("List View");
btnPanel.add(btnList);
add(btnPanel);
however, the buttons both try to take up the entire panel. If I leave it to a flow layout (I don't use btnPanel.setLayout(new BorderLayout()); in the above code), the buttons sit nicely in the center, but do not expand and share the btnPanel.
Thoughts? I'm new enough to Java that I could be going about this the wrong way from the start.
btnPanel.setLayout(new BorderLayout());
You didn't specify a constraint when you added the buttons to the panel. So both buttons are added to the CENTER. However, only one component can be added to the CENTER, so only the last one added is displayed.
You can try a different layout:
btnPanel.setLayout( new GridLayout(0, 2));
Then each button will be the same size and both buttons will fill the space available.
I'm using a JFrame with the size of 800x600.
what i'm trying to do is make this:
the black Panel has 2 other panels inside of him with the size of 300x300 each.
the result is that the black panel is to the left (as suposed) and the red panel in in the centre with a gap on top between the frame and the panel. also, if i remove the black panel the right panel is filling the whole frame...
this is the code:
//create the left part of the screen
JPanel leftPanels = new JPanel();
leftPanels.setLayout(new GridLayout(2,1));
leftPanels.setSize(new Dimension(300,600));
// just to illustrate the 2 panels inside of the black panel.
//leftPanels.add(new JPanel());
//leftPanels.add(new JPanel());
//create the right part
JPanel rightPanel = new JPanel();
rightPanel.setSize(new Dimension(500,600));
rightPanel.setBackground(Color.red);
this.add(leftPanels);
this.add(rightPanel);
this.validate();
this.repaint();
is there an easy way to fix this?
I also tried a Gridlayout on the JFrame but that gives me 2 panels of 400X600 each
First, use FlowLayout like this
setLayout(new FlowLayout(FlowLayout.LEFT));
Secondly, kindly use setPreferedSize rather than setSize for the JPanels
leftPanels.setPreferredSize(new Dimension(300,600));
I don't know what is cashRegister, but it looks like you are not adding the rightPanel to JFrame so make sure you add it.
Try to set the layout of the frame to null. Then use setBounds to position the panel.
If you are trying to set the panel relatively one from another set the frame layout to null
this.getContentPane().setLayout(null);
Then you will be able to place them absolutely.
For more info : Doing Without a Layout Manager (Absolute Positioning)
I have a JFrame window, and I'd like to add a scrollable JTable towards the middle of it. I have a method, called collectionTableScrollPane() that generates the JScrollPane (and I know this is guaranteed to work).
I then proceed to add it to my mainPanel panel. However, I'd like there to be some forced 30px padding on the left and right of the JScrollPane. Logically, I would create a holding JPanel with a centred FlowLayout, and add Box.createHorizontalStrut(30) either side of the JScrollPane.
JPanel tableHolderPanel = new JPanel(new FlowLayout());
mainPanel.add(tableHolderPanel);
tableHolderPanel.add(Box.createHorizontalStrut(30));
tableHolderPanel.add(collectionTableScrollPane());
tableHolderPanel.add(Box.createHorizontalStrut(30));
However, I'm getting a strange result, where the JScrollPane in the middle of the window (denoted by the arrows) sort of becomes ineffectual.
Does anyone know what the problem is?
Note that the JTable contains four rows, of which only two are visible.
I had some issues in the past when i used a JScrollPane inside a panel with a FlowLayout. The behaviour could be tricky, when the content grow, the horizontal scrollbar may appear or the FlowLayout should add a new line.
In your case, i will replace the FlowLayout by a BorderLayout :
JPanel tableHolderPanel = new JPanel(new BorderLayout());
mainPanel.add(tableHolderPanel);
tableHolderPanel.add(Box.createHorizontalStrut(30), BorderLayout.WEST);
tableHolderPanel.add(collectionTableScrollPane(), BorderLayout.CENTER);
tableHolderPanel.add(Box.createHorizontalStrut(30), BorderLayout.EAST);
As far as I'm aware, Box is suppose to be used with the BoxLayout, this may be causing you some issues. Instead, why not use a EmptyBorder on the tableHolderPane
BoxLayout accepting size that came from JComponents, the same issue with default FlowLayout pre_implemented for JPanel
you have to returns PreferredSize by overrode JPanel nested JScrollPane,
use another LayoutManager, e.g. GridBagLayout or todays MigLayout
use NestedLayout, by using BorderLayout where you put two JLabels (e.i. that returns PreferredSize) to the EAST and WEST area
everything depends if you really to want to create the empty area and if shoud be resiziable or not
I have a JPanel that uses BorderLayout and contains a jTable and a layeredPane. I need to use the layeredPane because it contains a jComboBox on top of a jTextPane. The problem is that when the user resizes the screen, the layeredPane doesn't resize. How can i fix this? I have something like this:
JPanel panel = new JPanel(new Borderlayout());
MyTable table = new MyTable();
panel.add(table, BorderLayout.CENTER);
JLayeredPane layeredPane = new JLayeredPane();
//addind things in the layered pane
panel.add(layeredPane, BorderLayout.PAGE_END);
Using a layout manager for the layered pane won't work, because i need components to be overlapped.
In the example you have posted JLayeredPane takes the SOUTH (BorderLayout.PAGE_END) place in the panel with BorderLayout. That means that the component in CENTER will take all additional space offered to the panel. And you have your table in CENTER.
Just place JLayeredPane in the CENTER and table in the NORTH to let the pane take all additional space.
More on BorderLayout:
http://docs.oracle.com/javase/tutorial/uiswing/layout/border.html
You also might want to read more on Swing layouts:
http://docs.oracle.com/javase/tutorial/uiswing/layout/index.html
common issue about JLayeredPane is that its childs would be placed by setBounds, because doesn't supports Standards LayoutManagers excluding Null Layout
have to add ComponentListener on event componentResized to change JPanels Bounds
for JComponents placed to the JPanel to use Standard LayoutManager
more than an alternative is to use the proper JLayer for Java7 based on custom JXLayer for Java6