So I've been troubleshooting this as much as possible, but I just wanted to create a function that would take in a buffered stream and then display the contents of that buffered stream in a scrollable pane. However every time I've run it the window doesn't show up at all. I'd like to know what I've done wrong here.
void show(BufferedOutputStream showFileContent)
{
String fileContent = showFileContent.toString();
JTextArea content = new JTextArea(fileContent);
JScrollPane scrollableScreen = new JScrollPane(content);
JPanel makeScreenAppear = new JPanel(new BorderLayout());
scrollableScreen.setViewportView(makeScreenAppear);
scrollableScreen.setVisible(true);
scrollableScreen.setSize(500,400);
}
Thank you for your help.
You are replacing the JTextArea with an empty JPanel as the viewport of the JScrollPane in this line of your code:
scrollableScreen.setViewportView(makeScreenAppear);
That's why you don't see the text. No need for the JPanel. Simple add the JScrollPane to the top-level window - which I assume is JFrame or JDialog.
Related
I tried a lot of layout managers but none could solve my problem:
I want the items in a scrollPane to keep their size (preferred or minimum) and not being resized (reduced) to fit the viewport Panel. Since if it is a JTextArea, and if the text area has blank space and it is bigger then the viewport, it would reduce it so the blank text area won't be shown. I want the blank text area to be shown for appearance issues.
Im stacking one item after another using BoxLayout, and it seems to me that for text areas the setMinimum method fails.
If the text area has blank space, then the scrollbar of the ScrollPane won't appear, instead it only appears it there are no blank space left.
Any solution?
JScrollPane materialPane = new FScrollPane();
this.materialPaneView = new TPanel();
this.materialPaneView.setMinimumSize(new Dimension((int)(WIDTH*0.95), (int)(HEIGHT/2)));
this.materialPaneView.setLayout(new BoxLayout(this.materialPaneView, BoxLayout.Y_AXIS));
materialPane.setViewportView(materialPaneView);
materialPane.setMinimumSize(new Dimension((int)(WIDTH*0.95), (int)(HEIGHT/2)));
for(Material mat: this.unit.getMaterial()){
this.addMaterial(mat);
}
centerPanel.add(sectionPane);
centerPanel.add(exercisePane);
centerPanel.add(materialPane);
this.add(upperPanel, BorderLayout.NORTH);
this.add(centerPanel, BorderLayout.CENTER);
public void addMaterial(Material mat){
JTextField matName = new JTextField(30);
JPanel fieldButtonPanel = new TPanel();
fieldButtonPanel.setLayout(new GridLayout(1,2));
JPanel fieldPanel = new TPanel(new FlowLayout(FlowLayout.LEFT));
JPanel deleteMatButtonPanel = new TPanel(new FlowLayout(FlowLayout.RIGHT));
matName.setText(mat.getName());
matName.setMaximumSize(new Dimension(FFont.def.getSize()*20, 30));
fieldPanel.add(matName);
JButton deleteMat = new JButton("Delete Material");
deleteMatButtonPanel.add(deleteMat);
fieldButtonPanel.add(fieldPanel);
fieldButtonPanel.add(deleteMatButtonPanel);
fieldButtonPanel.setAlignmentX(LEFT_ALIGNMENT);
JTextArea matText = new FTextArea(mat.getDesc(), (int)(WIDTH*0.95), (int)(HEIGHT/3.4));
matText.setMinimumSize(new Dimension((int)(WIDTH*0.95), (int)(HEIGHT/3.5)));
/*matText.setMaximumSize(new Dimension((int)(WIDTH*0.95), (int)(HEIGHT/3.4)));*/
matText.setText(mat.getDesc());
matText.setAlignmentX(LEFT_ALIGNMENT);
this.materialPaneView.add(fieldButtonPanel);
this.materialPaneView.add(matText);
matName.addActionListener(new ActionListener(){
#Override
public void actionPerformed(ActionEvent e) {
mat.setName(matName.getText());
}
});
HEIGHT and WIDTH are constants, and TPanel FScrollPane are my predefined transparent panels. The BoxLayout panel is the viewport of a scrollPane, and still, it would resize the text areas.
I am not sure i get what you are asking for so please tell me if i totally missed the point...
As far as i know the Viewport size is controlled by the component inside the JScrollPane and the JScrollPane size wont change no matter what happens to the viewport.
You either want to:
A) Resize the JScrollPane to the same size as it's content.
I would implement listeners to look for the content size change and resize the ScrollPane accordingly but you need to pay attention to resize the whole Hierarchy too.
B) You want to resize the viewport so that it fits in the JScrollPane? Y'know without scrollbars.
I had this problem and fixed it by using a ScrollablePanel component. Check this answer, follow the link to download the .class and use it to use a JPanel that resizes to fit the ScrollPane.
Those arent very detailed answers but i will need more information about what you are trying to do before expanding on it. And your code isnt complete, always share a code that we can CTRL+C/V and readily verify the problem in our end.
I have two files that I need to display in a program. I need to use JTabbedPane and each file should be displayed in its own tab. I can make the text appear in the tab, but the scroll bar won't appear, so I can't see all of the information in the file. How do I add the scroll bar to the text area?
I made one method that creates a panel with the text in it (this is for one file). Then, I made another method that has JTabbedPane and I added the panel to a tab.
Panel method:
private void makeTextPanel() throws IOException
{
textPanel = new JPanel();
textArea = new JTextArea();
textArea.setEditable(false);
//width: 770 height: 1000
textAreaDimensions = new Dimension(TEXT_AREA_WIDTH, TEXT_AREA_HEIGHT);
textArea.setPreferredSize(textAreaDimensions);
BufferedReader inputFile = new BufferedReader(new FileReader(FILE_ONE));
String lineOfText = inputFile.readLine();
while(lineOfText != null)
{
textArea.append("\n" + lineOfText);
lineOfText = inputFile.readLine();
}
// Add a scroll bar
scrollPane = new JScrollPane(textArea);
// Add the text area and scroll bar to the panel
textPanel.add(textArea);
textPanel.add(scrollPane);
}
Tabbed pane method:
private void makeTabbedPane() throws IOException
{
frame = new JFrame("Project");
tabbedPane = new JTabbedPane();
frame.add(tabbedPane, BorderLayout.PAGE_START);
// add panel to the tab
makeTextPanel();
tabbedPane.addTab("Tab 1", textPanel);
// dimensions
frameDimensions = new Dimension(FRAME_WIDTH, FRAME_HEIGHT);
frame.setPreferredSize(frameDimensions);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
To reiterate:
How do I make the scroll bar visible?
I set the height of the text area to 1000. Will the scroll bar be able to scroll through everything? If not, how do I set the height of the text area to fit everything in the file?
The component you want scroll bars for should always a child of the JScrollPane. Adding the textArea and then the scrollPane to that tabbedPane probably isn't doing what you think it is. Make sure that textArea is the child of scrollPane, and add just the scrollPane to the tabbedPane, ensuring you've specified a layout that dictates how the scrollPane is to take up the space you want within tabbedPane.
The scrollpane will automatically add scrollbars only when it decides the textArea is bigger than it can render in the space it's been given.
Question 1) The JScrollPane methods setVerticalScrollBarPolicy() and setHorizontalScrollBarPolicy() will allow you to force the scrollbars to be always visible.
Question 2) The "preferred" height of the textArea is what your scrollPane will use to determine the scrollbar behaviour (see this example). It's all taken care of for you. If not, you'd be forced yourself to consider font rendering height, how much text you put in the textArea etc.
Generally speaking, just throwing a JTextArea into a JScrollPane will see the desired behaviour you're seeking without you having to do anything "special" with JTextArea size.
Probably an easy fix, but Would be wonderful if someone can help me through this!
SO I have a method which creates a panel and also adds it to the JFrame.
The problem is, I want to keep recalling the method with slightly different text.
Although it does recall, it creates a new instance of it overtop of the previous one instead of replacing it.
}public void lyricPrinter(){
System.out.println(lyrics);
JTextArea textarea = new JTextArea(lyrics);
textarea.setBackground(Color.LIGHT_GRAY);
textarea.setEditable(false);
//JLabel textarea = new JLabel("not sure what this is...");
//textarea.setText("<html>"+lyrics+"</html>");
JScrollPane scroll = new JScrollPane (textarea,JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
//GUI.frame.remove(scroll);
GUI.frame.add(scroll);
GUI.frame.setVisible(true);
Every time the method runs, you are creating a new panel. In order to prevent this, you need to create only 1 instance of Panel Class, so that when the method runs, work will be done on same panel.
1-) Define Panel instance as local variable int your class.
2-) Instantiate the Panel in your "lyricPrinter" Method
3-) Immediately After, destroy the panel components using .removeAll()
It should work.
For your example;
JScrollPane scroll; //-->> somewhere in your class
public void lyricPrinter(){
System.out.println(lyrics);
JTextArea textarea = new JTextArea(lyrics);
textarea.setBackground(Color.LIGHT_GRAY);
textarea.setEditable(false);
//JLabel textarea = new JLabel("not sure what this is...");
//textarea.setText("<html>"+lyrics+"</html>");
**scroll = new JScrollPane (textarea,JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
scroll.removeAll();**
//GUI.frame.remove(scroll);
GUI.frame.add(scroll);
GUI.frame.setVisible(true);
I have a JScrollPane on a panel (which has many panels inside of it) and when I open the frame with the scroll pane on it, the fame is scrolled to the bottom. Is there anyway I can avoid this?
Here are some facts:
The panel the scroller is on contains multiple panels. Some of these panels have text fields. I have tried to set the carat of the text fields to 0 and this did not work.
I know there should be actual code, but when I tried to make a mock pane (as the one I am using is intertwined with a lot of code) it is not replicating the issue.
The panel that is being scrolled is being generated using a loop that generates a series of questions... so a text box, a said amount of buttons/answers, and a text box and label that shows the amount of points for each question.
The last elements of my panel that is being scrolled are a JTextArea and a JLabel.
Below is the code to declare those.
Is there anyone out there that could at least throw out an idea of what would be making the scroll pane automatically go to the bottom?
Here is the declaration of the pane and the panels inside/outside of it
JPanel newPanel = new JPanel(new BorderLayout(0, 0));
JPanel showPanel = new JPanel();
BoxLayout layout = new BoxLayout(showQuizPanel, BoxLayout.Y_AXIS);
showQuizPanel.setLayout(layout);
buttonPanel = new JPanel(new FlowLayout(FlowLayout.RIGHT));
buttonPanel.setBackground(Color.white);
newPanel.setBackground(Color.white);
showPanel.setBackground(Color.white);
populateButtonPanel();
populateShowPanel(showPanel, buttonPanel);
populateQuestions(showPanel);
JScrollPane scrollPane = new JScrollPane(showPanel, JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED, JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
scrollPane.getViewport().setBackground(Color.WHITE);
scrollPane.setAlignmentX(JScrollPane.CENTER_ALIGNMENT);
scrollPane.getVerticalScrollBar().setUnitIncrement(16);
scrollPane.getVerticalScrollBar().setValue(0);
scrollPane.getViewport().setViewPosition(new Point(0,0));
newPanel.add(scrollPane, BorderLayout.CENTER);
return newPanel;
code to declare last elements on page
JPanel pPanel = new JPanel(new FlowLayout(FlowLayout.CENTER));
pPanel.setBackground(Color.WHITE);
pPanel.add(qValue);
pPanel.add(new JLabel("Points"));
qArea.add(pPanel);
qArea.add(Box.createVerticalStrut(50));
qValue.setCaretPosition(0);
Thanks!
I believe that when you add text to a text area when building the GUI, the scroll pane will scroll to make the text area visible.
So basically you need to reset the scroll pane to the top.
You can use code like the following after adding all components to the scroll pane:
SwingUtilities.invokeLater(new Runnable()
{
public void run()
{
scrollPane.getViewport().setViewPosition( new Point(0, 0) );
}
});
The invokeLater() adds the code to the end of the Event Dispatch Thread (EDT) so that it gets executed after the GUI is visible.
Of course this code assumes that you are creating the rest of the GUI properly on the EDT.
All,
I am running into an issue using JTextArea and JScrollPane. For some reason the scroll pane appears to not recognize the last line in the document, and will only scroll down to the line before it. The scroll bar does not even change to a state where I can slide it until the lines in the document are two greater than the number of lines the textArea shows (it should happen as soon as it is one greater).
Has anyone run into this before? What would be a good solution (I want to avoid having to add an extra 'blank' line to the end of the document, which I would have to remove every time I add a new line)?
Here is how I instantiate the TextArea and ScrollPane:
JFrame frame = new JFrame("Java Chat Program");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Container pane = frame.getContentPane();
if (!(pane.getLayout() instanceof BorderLayout)) {
System.err.println("Error: UI Container does not implement BorderLayout.");
System.exit(-1);
}
textArea = new JTextArea();
textArea.setPreferredSize(new Dimension(500, 100));
textArea.setEditable(false);
textArea.setLineWrap(true);
textArea.setWrapStyleWord(true);
JScrollPane scroller = new JScrollPane(textArea);
scroller.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS);
pane.add(scroller, BorderLayout.CENTER);
Here is the method I use to add a new line to textArea:
public void println(String a)
{
textArea.append(" "+a+"\n");
textArea.setCaretPosition(textArea.getDocument().getLength());
}
Thanks for your help,
Jonathan
EDIT: Also, as a side note, with the current code I have to manually scroll down. I assumed that setCaretPosition(doc.getLength()) in the println(line) method would automatically set the page to the bottom after a line is entered... Should that be the case, or do I need to do something differently?
The problem is textArea.setPreferredSize(new Dimension(500, 100));
Remove that. Set the perferredSize of the scrollpane or the size of your frame instead
Is this a solution? I didn't test it, so please don't kill me.
scroller.getVerticalScrollBar().setValue(pane.getVerticalScrollBar().getMaximum());