I'm currently learning more about Java. I'm working on creating a GUI which is able to 'translate' amino-acid characters into their 3-letter codes.
I've got everything working as intended, but I'm still struggling to understand how I can resize the text inside my JScrollpane to not exceed the width. (Example in picture)
Do I just need to change some settings or maybe add '\n's to fit the JTextArea? Here's the code:
Thanks in advance!
private void createGUI() {
Container window = this.getContentPane();
window.setLayout(new FlowLayout());
panel = new JPanel();
inputField = new JTextField();
startButton = new JButton("Convert to 3-letter code");
display = new JTextPane();
scroll = new JScrollPane(display);
//CUSTOMIZE GUI OBJECTS
inputField.setPreferredSize(new Dimension(200, 20));
display.setPreferredSize(new Dimension(400, 300));
startButton.addActionListener(this);
//SETTING UP TEXTAREA
display.setEditable(false);
scroll.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS);
scroll.setHorizontalScrollBarPolicy(ScrollPaneConstants.HORIZONTAL_SCROLLBAR_NEVER);
panel.setLayout(new BorderLayout());
panel.add(scroll, BorderLayout.CENTER);
//
window.add(inputField);
window.add(startButton);
window.add(panel);
}
Better use a JTextArea instead of a JScrollPane since the best that the JScrollPane can do is to dynamically resize (Dynamically Resize a JScrollPane?)
I changed JTextPane display to a JTextArea object and changed 'display.setLineWrap(true);'
This fixed the issue I was having with JTextPane.
To answer the question in the title: How do I resize the text inside my JScrollpane
Inside your scrollpane you have some JComponent. Either that JComponent is fully visible since it is smaller or equal to the JScrollpane's viewport. Or it is bigger, in which case the JScrollpane will start displaying scrollbars and the relevant part.
To resize the text you will just have to tell the JComponent inside the JScrollpane to display the text differently. Depending on the JComponent you use this method may vary. Here some examples:
In a JLabel and most other components, increase the font size (How to change the size of the font of a JLabel to take the maximum size)
In a JLabel, switch to a multiline label (Multiline text in JLabel)
In a JTextArea, turn on word wrapping and line wrapping
In a JEditorPane you can even use markup inside the document to use different font sizes at the same time
Related
When I add both of them to SOUTH using BorderLayout, only the JTextArea appears. I'm using the text field as an input which is then displayed in the text area as an output above it with some other text.
It works if I set the text area to NORTH but it doesn't look great.
JPanel cmdPanel = new JPanel(new BorderLayout());
field = new JTextField(20);
cmdPanel.add(field, BorderLayout.SOUTH);
JTextArea output=new JTextArea();
output.setEditable(false);
output.setLineWrap(true);
cmdPanel.add(output, BorderLayout.SOUTH);
This image shows how it looks now with the TextArea set to NORTH.
I'm just trying to have it appear over the TextField and move up
the screen as outputs are added.
You have not provided a minimal, reproducible example but from the screen capture of your running app, it looks like you are explicitly setting the size of the JFrame. Rather than doing that, you should call method pack. Note that you should call that method after you have added both your JTextField and JTextArea to the cmdPanel and also after you have added cmdPanel to the JFrame. Also you should call method setVisible on the JFrame after calling method pack().
You should also make sure that the JTextArea has a preferred size before adding it to cmdPanel. One way to do this is by calling the constructor that takes the number of rows and columns parameters.
Maybe also wrap the JTextArea in a JScrollPane and make that the "center" component of cmdPanel?
JPanel cmdPanel = new JPanel(new BorderLayout());
field = new JTextField(20);
cmdPanel.add(field, BorderLayout.SOUTH);
JTextArea output=new JTextArea(10, 20);
output.setEditable(false);
output.setLineWrap(true);
JScrollPane scrollPane = new JScrollPane(output);
cmdPanel.add(scrollPane, BorderLayout.CENTER);
It is not possible to add two components in the same position (i.e BorderLayout.PAGE_END). To add more components in the same position, you should create a JPanel, add the components on it and then add the JPanel to the desirable position (i.e BorderLayout.PAGE_END).
I have a JLabel with some text in it. This JLabel takes up the whole bottom side of my JFrame. I have changed the background of it to yellow, and the whole bottom side becomes yellow. Is there any way to make it look like the text, which is within the JLabel, is being "highlighted" with only the text having a background color of yellow, and the rest having a different color? The top part of my JFrame is a JPanel.
combo.addItemListener(new ItemChangeListener());
JPanel container = new JPanel();
container.setBackground(Color.BLUE);
response.setFont(new Font("Times new Roman", Font.BOLD, 40));
response.setHorizontalAlignment(SwingConstants.CENTER);
response.setBackground(Color.YELLOW);
response.setOpaque(true);
add(response , BorderLayout.CENTER);
container.add(selectone);
container.add(combo);
this.add(container, BorderLayout.NORTH);
There is a very simple way to do that - use HTML in the text of the label. Mind you, Swing interprets a pretty old version of HTML, that doesn't meet today's standards.
JLabel response = new JLabel( "<html><span bgcolor=\"yellow\">This is the label text</span></html>" );
Nowadays, one should work with style sheets. But if you want to do that, you should probably switch from Swing to JavaFX.
For further details on using HTML in Swing components, see the applicable part of the tutorial.
Use a wrapper panel that respects the preferred size of the label:
JLabel label = new JLabel("...");
label.setOpaque( true );
label.setBackground(...);
JPanel wrapper = new JPanel();
wrapper.add( label );
frame.add(wrapper, BorderLayout.CENTER);
The default layout for a JPanel is a FlowLayout that is horizontally center aligned.
If you want both horizontal and vertical centering then use a GridBagLayout on the panel, with the default GrigBagConstraints when you add the label to the panel.
I'm begging with JAVA Swing. But when I use my JPanel can I only add one JTextPane. How can I do so I can add multiple.
Here's is what I do
JPanel panel = new JPanel();
JTP = new JTextPane();
JTP.setBackground(Color.black);
JTP.setForeground(Color.WHITE);
Lines = new JTextPane();
new BorderLayout();
panel.add(JTP, BorderLayout.WEST);
new BorderLayout();
panel.add(Lines, BorderLayout.EAST);
And there's is no errors. I know i not have giving you all the code but it's work.
JPanel panel = new JPanel();
This create a JPanel which uses a FlowLayout by default.
new BorderLayout();
This statement does nothing because you don't have a reference to the BorderLayout, to you can't use it as a layout manager on any panel.
But there is no need to use a BorderLayout for you panel, since a FlowLayout can display multiple components at one time. The problem is that the text pane needs a "preferred size" before it can be using with a layout manager.
For something simple why don't you just start with a JTextArea since it is easer to use. You can create the text area with code like:
JTextArea textArea = new JTextArea(5, 20);
and it will create a text area with a preferred size to display 5 lines of text with about 20 characters on each line.
Then you create two text areas and add them to your panel.
Of course any time you use a text area you should probably add it to a JScrollPane:
JScrollPane scrollPane = new JScrollPane( textArea );
panel.add( scrollPane );
and then add the scrollPane to the panel.
From the looks of it, you are only seeing one TextField because you aren't properly using BorderLayout.
EDIT: You said you want to change background colors, you can do that to a JTextField and a JTextArea. Check the docs! It's one line of code.
You are supposed to explicitly set the layout of the JPanel to BorderLayout like this :
JPanel panel = new JPanel(new BorderLayout());
OR
JPanel panel = new JPanel();
panel.setLayout(new BorderLayout());
Even simpler, you don't need to use BorderLayout.
JPanel, by default, is assigned a FlowLayout which is capable of neatly handling more than one JComponent. Try using a JTextField or JTextArea instead of a JTextPane.
If you need to use a JTextPane because of a certain layout goal, then try the code examples I listed above.
Good luck. Don't be afraid to refer to the official Oracle docs/tutorials for Swing Layouts
http://docs.oracle.com/javase/tutorial/uiswing/layout/visual.html
I want to set the size of the JTextPane according to the size of the panel so that when i add other panels, it changes accordingly. But it just gives a small text pane in the center and when i add some text, it's size changes accordingly.
JPanel panel = new JPanel();
JTextPane txt = new JTextPane();
JScrollPane pane = new JScrollPane();
pane.add(txt);
panel.add(pane,BorderLayout.CENTER);
add(pane);
now the jtextpane just appears at the center of the screen like a small box. I want it to appear according to the size of the panel
JPanel uses FlowLayout by default which sizes components according to their preferred sizes. You can use BorderLayout which will use the maximum area possible.
Also using constraints such as BorderLayout.CENTER has no effect unless the container is actually using BorderLayout. Dont add components to the JScrollPane. This will replaces all components within the view of the component. Instead set the JTextPane as the ViewPortView, for example
JPanel panel = new JPanel(new BorderLayout());
JTextPane txt = new JTextPane();
JScrollPane pane = new JScrollPane(txt);
// pane.add(txt); remove
panel.add(pane, BorderLayout.CENTER);
Read:
How to Use BorderLayout
How to Use Scroll Panes
You added pane twice. Add panel to your base (a JFrame?) instead and remember to actually set your JPanel to use BorderLayout.
I have added a scroll pane to the main panel of my frame. But it doesn't display properly, here's what I get that appears on the right:
http://postimage.org/image/extp3ncql/
here is the code:
JScrollPane jScrollPane = new JScrollPane(area);
jScrollPane.setHorizontalScrollBarPolicy(JScrollPane.HORIZONTAL_SCROLLBAR_ALWAYS);
jScrollPane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
jScrollPane.setViewportBorder(new LineBorder(Color.RED));
pane.add(jScrollPane, BorderLayout.EAST);
EDIT: Forgot to mention that area is a label.
1) Use another proper LayoutManager, I'd suggesst use Box or directly BoxLayout
or
2) all areas excluding BorderLayout.CENTER acepted PreferredSize came from JComponent
3) if your area is JTextArea the you can pretty to set JTextArea(int rows, int columns)