I wrote a simple gui with DesignGridLayout as layout manager.
I have a 2 JTextFields, beneath them a JScrollPane containing a JTextArea, and right under it I have a button.
Upon maximizing the JFrame, everything is stretching out nicely to fill the screen.
The problem starts when I try to restore the Frame to it's original size. the JScrollFrame Vertical size remains too large, and the Button is not shown, since it is covered by the too big Jscrollpane.
The problem is the same for manual resizing. The JScrollPane sets a new value for it's vertical size according to how much I stretch it.
I tried overriding the getScrollableTracksViewportHeight() method from Scrollable interface, but it had no affect. In addition, I had this entire setting inside a Jpanel which I removed, but it's still the same.
Any insights would be appreciated.
edit: added samples of code.
This code creates most of the Gui:
DesignGridLayout layout = new DesignGridLayout(frame);
layout.row().grid().empty().add(new JLabel("someText1"), someText1);
layout.row().grid().empty().add(new JLabel("someText2"), someText2);
layout.emptyRow();
layout.row().grid().add(new JSeparator());
layout.row().grid().empty().add(titleLabel).empty();
layout.row().grid().add(textarea("",5,6));
layout.row().grid().empty().add(button).empty();
This code creates The JScrollPane:
private JScrollPane textarea(String content, int rows, int columns)
{
JTextArea textArea = new JTextArea(rows, columns);
JScrollPane scrollPane = new JScrollPane(textArea);
return scrollPane;
}
Related
I am trying to use some java gui in my matlab code.
I want to create a Jpanel containing lots of buttons , and add this Jpanel to a JscrollPane to be able to scroll up and down, right and left through the Jpanel.
I tried using JavaComponent() function as described in : http://undocumentedmatlab.com/blog/javacomponent
here is my code:
[jpanel1, hpanel1] = javacomponent('javax.swing.JPanel');
[jButton1, hButton1] = javacomponent('javax.swing.JButton');
[jscroll, hscroll] = javacomponent('javax.swing.JScrollPane');
jButton1.setText('Click again!');
set(hButton1,'position',[5 5 50 50])
set(hpanel1,'position',[50 50 500 500],'BackgroundColor','white');
jpanel1.add(jButton1);
jscroll.add(jpanel1);
The panel and button are created but I can't find the scrollpane, tried setting the jscroll to visible with no results.
WHat am I missing out??
You only need to use javacomponent once, to display the outer-most java container, i.e. JScrollPane in your case. Just assemble your components inside JPanel container and then pass that to JScrollPane constructor.
Note that it is safer to create your objects with javaObjectEDT so that subsequent method calls run on EDT - otherwise you could face a deadlock / race condition.
Finally, note how you can use getpixelposition and 'normalized' units for the container created by javacomponent to make your JScrollPane fill the entire parent drawing area, and behave better on resizing.
jButton1 = javaObjectEDT('javax.swing.JButton', 'Button 1');
jButton2 = javaObjectEDT('javax.swing.JButton', 'Button 2');
jPanel = javax.swing.JPanel();
jPanel.add(jButton1);
jPanel.add(jButton2);
jScrollPane = javax.swing.JScrollPane(jPanel);
hFig = figure();
hParent = uicontainer('Parent',hFig);
parentPixelPos = getpixelposition(hParent);
pos = [1,1,parentPixelPos(3),parentPixelPos(4)]; % fill the parent uicontainer completely
[~, hContainer] = javacomponent(jScrollPane, pos, hParent);
set(hContainer, 'Units', 'normalized'); % better behavior on resizing
jscroll.add(jpanel1);
You should never add components to a scroll pane. A JScrollPane has its own custom layout manager to display the scrollbars and the viewport.
So instead you need to add the panel to the viewport:
jscroll.setViewportView( jpanel1 );
However, this may still not work as the following code looks like it is trying to set the size/location of the component which implies a null layout is being used:
set(hButton1,'position',[5 5 50 50])
Normally it is the responsibility of the layout manager to determine the size/location of a component and the scrollbars of the scrollpane will only be displayed is the preferred size of the panel is greater than the size of the scrollpane.
I don't know that the benefit of using MatLab is. I suggest you just use normal Swing. See examples from the Swing tutorial on Using Layout Managers.
So recently i discovered Scrollpanes and have been trying implement one properly.
After a bit of searching i found this section of code
public void create() {
batch = new SpriteBatch();
skin = new Skin(Gdx.files.internal("data/uiskin.json"));
stage = new Stage();
gamelog = new Label("Start", skin);
gamelog.setAlignment(Align.center);
gamelog.setWrap(true);
Table scrollTable = new Table();
scrollTable.add(gamelog);
scrollTable.row();
scroller = new ScrollPane(scrollTable);
Table table = new Table();
table.setFillParent(true);
table.add(scroller).fill().expand();
Now for the most part this code works well. a scrollpane is actually created and i can dynamically add text to it. my issue however is the size of the scrollpane takes up the whole screen, and initial text is centered in the middle of the scrollpane(so in the middle of the screen) and only starts to scroll once enough text has been added to take up the whole height of the screen.
Rather than expanding on its own what i actually want is for the scrollpane to take up just a small section at the bottom of the screen.
I have tried setting the bounds of the tables and of the scrollpane but the closest i have come is merely moving the scrollpane downwards(meaning the last text added is off screen and not in view. Its s if it completely ignores any width or height set and just expands on its own.
I figure i could get the desired effect by simply using a set of labels at the bottom of the screen and change their text dynamically but then the scroll feature would be lost. so before i do this i was hoping someone could shed some light on wether or not it is possible to resize and set a scrollpanes bounds?
Table uses cells to size its components. When you add a component to a table it returns the table's cell which holds that component. You can then use the cell to set the size of the component.
In your original code try this:
table.add(scroller).size(460, 200);
And if you want to change the scrollpane size after adding it to the table, you can get the cell from the table and then set its size like this:
table.add(scroller);
...
table.getCell(scroller).size(460, 200);
And here is the API for Cell:
https://libgdx.badlogicgames.com/nightlies/docs/api/com/badlogic/gdx/scenes/scene2d/ui/Cell.html
I stumbled across a solution with trial and error.
the following code works for me and allows the scrollpane to be resized and positioned. The main culprit seems to be the use of table.setFillParent(true); and the order in which you try to set the parent tables bounds.
batch = new SpriteBatch();
skin = new Skin(Gdx.files.internal("data/uiskin.json"));
stage = new Stage();
gamelog = new Label("Start", skin);
gamelog.setAlignment(Align.center);
gamelog.setWrap(true);
Table scrollTable = new Table();
scrollTable.add(gamelog);
scrollTable.row();
scroller = new ScrollPane(scrollTable);
Table table = new Table();
table.setBounds(10, 10, 460, 200);
table.add(scroller).fill().expand();
scrollTable.debug();
scroller.debug();
table.debug();
stage.addActor(table);
I have this code which I don't understand:
JFrame jframe = new JFrame("Risultati protocolli cercati");
jframe.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel body = new JPanel();
Container c = jframe.getContentPane();
body.setSize(100, 100);
body.setLayout(new GridLayout(1000, 1));
for (int i = 0; i < 1000; i++)
body.add(new JLabel("JLabel " + i));
JScrollPane jsp = new JScrollPane(body);
c.add(jsp);
jframe.setSize(100, 100);
//jframe.add(body);
jframe.setVisible(true);
If I leave the penultimate line commented then everything appears, both labels and scroll. Instead if I uncomment that line, I see nothing. Only the JFrame. Why does it happens? For the main window of my program I had to perform jframe.add(body)...
Instead if I uncomment that line, I see nothing. Why does it happens?
The below line
jframe.add(body);
internally calls
jframe.getContentPane().add(body);
JFrame by default uses BorderLayout and add(component) method directly add it in the center section, if you add again then last one is replaced with latest one.
You can use overloaded add() method of JFrame to add it in another section east, west, north and south as shown in below snapshot:
for e.g.:
frame.add(comp,BorderLayout.NORTH); // add in north section
frame.add(comp,BorderLayout.WEST); // add in west section
You can use other Layout Managers as well as per the design or your application:
It's worth reading How to Use BorderLayout
One more suggestion:
Use frame.pack() instead of frame.setSize() that fits the components as per component's preferred size.
Interesting problem caused by the layout managers.
A component can only have a single parent. First you add the "body" to the scrollpane but then the "body" gets removed from the scrollpane when you add it to the content pane of the frame (for the reasons mentioned by #braj). Not a big deal as it just means you won't see any scrollbars.
Since the component is directly added to the content pane you should still see the labels however they do not display and this is the confusing part. Change your code to use "100" for the GridLayout and the number of components you create in the loop. When the frame first displays the panel will be empty. Now, increase the height of the frame and you will see the components appear. What is happening is that you are trying to paint too many components in a small area and because of rounding issues the height of every component becomes 0, so there is nothing to paint. When you increase the height to at least 100 pixels every component can now be 1 pixel high so you get garbage.
The only solution is to keep the "body" panel in the scrollpane so that all components will be displayed at their preferred size. Then you can scroll through all the components as required.
A tip for when using a GridLayou. You can use:
body.setLayout(new GridLayout(0, 1));
Then means the grid will have unlimited rows and a single column.
I am having a simple problem I guess, that u should know how to solve..
I am trying to do this:
I have a JFrame.
Then I create a JPanel and set his layout to GridLayout(5,5)
Finnaly I add this JPanel to the Container of my JFrame.
When I try to get the width of my panel it shouldnt give me 0 right?
I do this: System.out.println(mypanel.getSize().getWidth()); and it says that is zero :c
why ??
I wanna know the size so I can divide per 5 and know how much to paint for each label, this will be a grid of labels..
Thanks alot in advance...
public janela(){
window = new JFrame("teste");
window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
window.setSize(300,300);
contentor = window.getContentPane();
interior = new JPanel();
interior.setLayout(new GridLayout(5,5));
contentor.add(interior);
System.out.println(interior.getSize().getWidth()); //it says 0 ?!?! why??
}
thanks alot in advance guys!!!!
Panels are sized based on their layout. specifically when they are shown and doLayout() is called for you. doLayout() figures out what the appropriate size for your panel is based on the contents of the panel, and the layout manager in force. Since your panel has nothing in it, the appropriate size is 0, 0.
If you will never have anything in the panel, and want to circumvent this (0, 0) size, you can override getPreferredSize() of the panel to return a size that you want the panel to respect for layout.
I have a JPanel that I want to use to contain 3 vertical components:
a JLabel
a JTextField
a JScrollPane
I want all 3 components to fill the JPanel's width. I want the JLabel and JTextField to use their normal heights and the JScrollPane to use the rest.
BoxLayout almost works, except it seems like the JTextField and JScrollPane share the "extra" space when the JPanel is made large.
What can I do?
Create a BorderLayout. Put the JScrollPane in its center.
Create a JPanel with a BoxLayout. Put the JLabel and JTextField in that, vertically. Put that JPanel into the NORTH side of the BorderLayout.
GridBagLayout is pretty handy. You can control anything you need and you can control only what you need. You're probably going to be interested in only the vertical parameters.
You could also use DesignGridLayout as follows:
DesignGridLayout layout = new DesignGridLayout(thePanel);
layout.row().center().fill().add(theLabel);
layout.row().center().fill().add(theTextField);
layout.row().center().fill().add(theScrollPane);
This should exactly behave as you describe.
Each call to row() creates a new row in the panel.
The calls to fill() make sure that each component uses the whole available width.
A few advantages of using DesignGridLayout here are:
only one LayoutManager for the whole
panel
automatic borders and inter-rows spacing