I created two panels and a main panel. Each panel contains a very large image, and I wanted both of them to be scroll-able to see the rest of the image. But when I add the two panels in the main panel and run it, the first panel is soo big that it covers the second panel. How would I implement ScrollPane for both panels?
import java.awt.BorderLayout;
import javax.swing.*;
public class BoardFrame extends JFrame {
JPanel mainPanel = new JPanel(new BorderLayout());
JLabel jLabel = new JLabel();
JPanel jPanelNorth = new JPanel();
JScrollPane scrollPane = new JScrollPane();
JLabel jLabel2 = new JLabel();
JPanel jPanelSouth = new JPanel();
JScrollPane scrollPane2 = new JScrollPane();
public BoardFrame() {
jLabel.setIcon(new ImageIcon("an image here"));
jPanelNorth.add(jLabel);
jLabel2.setIcon(new ImageIcon("an image here"));
jPanelSouth.add(jLabel2);
mainPanel.add(jPanelNorth, BorderLayout.NORTH);
mainPanel.add(jPanelSouth, BorderLayout.SOUTH);
add(mainPanel);
//where would I use this?
//scrollPane.setViewportView();
}
}
Each panel contains a very large image>
//JPanel mainPanel = new JPanel(new BorderLayout());
JPanel mainPanel = new JPanel(new GridLayout(0, 1));
You may want to use a GridLayout so that each scroll pane takes up half the frame so as much of each image as possible is displayed.
//JScrollPane scrollPane = new JScrollPane();
JScrollPane scrollPane2 = new JScrollPane(jPanelNorth);
The easiest way to use the scroll pane is to create the scrollpane with the component you want displayed and the scrollpane will add the component to the viewport for you.
//mainPanel.add(jPanelNorth, BorderLayout.NORTH);
mainPanel.add(scrollPane); // don't need the constraint when using GridLayout.
Then you add the scrollPane to the main panel, since the scrollpane contains the panel with the image.
it seems to use grid layout is much better than using border layout , in this case :
import java.awt.BorderLayout;
import javax.swing.*;
public class BoardFrame extends JFrame {
//1. use GridLayout with 2 rows and 1 column .
JPanel mainPanel = new JPanel(new GridLayout(2,1));
JLabel jLabel = new JLabel();
JPanel jPanelNorth = new JPanel();
JScrollPane scrollPane = new JScrollPane();
JLabel jLabel2 = new JLabel();
JPanel jPanelSouth = new JPanel();
JScrollPane scrollPane2 = new JScrollPane();
public BoardFrame() {
jLabel.setIcon(new ImageIcon("an image here"));
jPanelNorth.add(jLabel);
jLabel2.setIcon(new ImageIcon("an image here"));
jPanelSouth.add(jLabel2);
//2.you should place .setViewportView() here :
scrollPane.setViewportView(jPanelNorth);
scrollPane2.setViewportView(jPanelSouth);
mainPanel.add(scrollPane);//is in the top ("North")
mainPanel.add(scrollPane2);//next ("South")
//3.use setContentPane instead of add()
setContentPane(mainPanel);
}
}
Related
I am making a Java application with tabbed pane, I want some panes to have the same panel layout and structure, I don't want to clutter my code by writing the same code over and over again, so I created a method that returns a JPanel with a structure I want the pane to have.
I am initialising new variables and taking them to the method . My problem is that after I create a panel I can not do anything else in it because it doesn't show up. I can not add labels etc, etc (although if I add the label in the method it does show).
My question is it possible to somehow change the code I've written to make it possible to change it after the panel is returned?
JPanel panel2 = panel2(); // this code bit is in the constructor
JPanel mainPanel = new JPanel(); //Variables needed to create a panel
JPanel LeftPanel = new JPanel();
JPanel RightPanel = new JPanel();
JSplitPane splitPaneH = new JSplitPane();
JPanel panelTop = new JPanel();
JPanel panelBottom = new JPanel();
private JPanel panel2() {
JPanel newPanel = new JPanel();
CreateAPanel(newPanel, LeftPanel,RightPanel,splitPaneH, panelTop,panelBottom);
JLabel label = new JLabel ("lalala");
LeftPanel.add(label,BorderLayout.CENTER);
return newPanel;
}
private JPanel CreateAPanel(JPanel mainPanel, JPanel LeftPanel,JPanel RightPanel, JSplitPane splitPaneH, JPanel panelTop, JPanel panelBottom){
mainPanel.setPreferredSize(new Dimension(1100, 630));
mainPanel.setLayout(new BorderLayout());
LeftPanel = new JPanel();
RightPanel = new JPanel();
splitPaneH = new JSplitPane(JSplitPane.VERTICAL_SPLIT);
panelTop = new JPanel();
panelBottom = new JPanel();
splitPaneH.setTopComponent(panelTop);
splitPaneH.setBottomComponent(panelBottom);
splitPaneH.setDividerLocation(300);
splitPaneH.setPreferredSize(new Dimension(800,630));
mainPanel.add(LeftPanel, BorderLayout.WEST);
mainPanel.add(RightPanel,BorderLayout.EAST);
LeftPanel.setBackground(Color.RED);
LeftPanel.setPreferredSize(new Dimension (300,630));
RightPanel.add(splitPaneH);
return mainPanel;
}
you do not use your return value...
your method CreateAPanel(...) creates the desired panel but you just don't use it
you should adjust your method panel2() in like this:
private JPanel panel2()
{
//JPanel newPanel = new JPanel(); don't create a new panel!
//CreateAPanel(newPanel, LeftPanel,RightPanel,splitPaneH, panelTop,panelBottom);
//instead do this:
JPanel newPanel = CreateAPanel(newPanel, LeftPanel,RightPanel,splitPaneH, panelTop,panelBottom);
JLabel label = new JLabel ("lalala");
LeftPanel.add(label,BorderLayout.CENTER);
return newPanel;
}
It's totally possible to add components to the Panel object afterwards. The only mistake that you have made is that "inside the method body you create new JPanel instances to replace with original param references" so when the method returns there is no effect on the original objects. I suggest doing something different as this:
private JPanel[] CreateAPanel(JPanel mainPanel)
{
mainPanel.setPreferredSize(new Dimension(1100, 630));
mainPanel.setLayout(new BorderLayout());
JPanel leftPanel = new JPanel();
JPanel rightPanel = new JPanel();
JSplitPane splitPaneH = new JSplitPane(JSplitPane.VERTICAL_SPLIT);
JPanel panelTop = new JPanel();
JPanel panelBottom = new JPanel();
splitPaneH.setTopComponent(panelTop);
splitPaneH.setBottomComponent(panelBottom);
splitPaneH.setDividerLocation(300);
splitPaneH.setPreferredSize(new Dimension(800,630));
mainPanel.add(leftPanel, BorderLayout.WEST);
mainPanel.add(rightPanel,BorderLayout.EAST);
leftPanel.setBackground(Color.RED);
leftPanel.setPreferredSize(new Dimension (300,630));
rightPanel.add(splitPaneH);
return new JPanel[]{mainPanel, leftPanel, rightPanel, panelTop, panelBottom};
}
If you want to change or add some more components inside result JPanel you get you can set names to all your components when you create them:
JPanel newPanel = new JPanel();
newPanel .setName("leftPanel");
resultPanel.add(newPanel, BorderLayout.WEST);
Then when you get resultPanel you can get it's components:
Component[] componentList = resultPanel.getContentPane().getComponents();
JPanel leftPanel = null;
for (Component component: componentList) {
if (Objects.equals(component.getName(), "leftPanel")) {
leftPanel = (JPanel) component;
}
}
if (leftPanel != null) {
// do something
}
I want to create the following GUI with Java Swing.
Since I'm not experienced enough with Java Swing, I'm not sure how to exactly recreate that GUI.
I've tried using GridLayout which looks like this:
I've tried other LayoutManagers but due to my inexperience, I couldn't get anything even remotely resembling the GUI I want to achieve.
I probably have to use GridBagLayout but I've tried it and simply wasn't able to get anything done.
I'm not sure how to exactly use GridBagLayout, especially since there is a variance of the amount of colums needed (2, 2 and then 3).
Here is the code used for creating the second GUI:
import java.awt.*;
import javax.swing.*;
public class GUITest extends JFrame {
public GUITest() {
super("Testing Title");
Container pane = getContentPane();
pane.setLayout(new GridLayout(3,1));
pane.add(getHeader());
pane.add(getTextArea());
pane.add(getButtonPanel());
}
public JComponent getHeader() {
JPanel labelPanel = new JPanel();
labelPanel.setLayout(new GridLayout(1,2));
labelPanel.setSize(getPreferredSize());
JLabel labelLocal = new JLabel("Left value: ", JLabel.CENTER);
JLabel labelDB = new JLabel("Right value: ", JLabel.CENTER);
labelPanel.add(labelLocal);
labelPanel.add(labelDB);
return labelPanel;
}
public JComponent getTextArea() {
JPanel textPanel = new JPanel();
textPanel.setLayout(new GridLayout(1,2,5,0));
JTextArea testTextArea = new JTextArea();
testTextArea.setEditable(false);
JScrollPane sp1 = new JScrollPane(testTextArea);
JTextArea testTextArea2 = new JTextArea();
JScrollPane sp2 = new JScrollPane(testTextArea2);
testTextArea2.setEditable(false);
testTextArea.setText("Hello Hello Hello\nTesting!\ntesterino\ntesteroni");
testTextArea2.setText("Hello Hello Hello\nTesting!\ntest\nABC123\ncdef123\nhijk123");
textPanel.add(sp1);
textPanel.add(sp2);
return textPanel;
}
public JComponent getButtonPanel() {
JPanel inner = new JPanel();
inner.setLayout(new FlowLayout((FlowLayout.CENTER),0,100));
inner.add(new JButton("Do something"));
inner.add(new JButton("Do something different"));
inner.add(new JButton("Do something even more different"));
return inner;
}
public static void main(String[] args) {
GUITest e = new GUITest();
e.setSize(700, 500);
e.setVisible(true);
e.setResizable(false);
e.setDefaultCloseOperation(EXIT_ON_CLOSE);
e.setLocationRelativeTo(null);
}
}
I'm thankful for any kind of support!
You could try something like this:
import javax.swing.*;
import javax.swing.border.EmptyBorder;
import java.awt.*;
public class Example {
public static void main(String[] args) {
JFrame jFrame = new JFrame();
jFrame.setTitle("Testing Title");
jFrame.setLocationRelativeTo(null);
JPanel mainPanel = new JPanel(new BorderLayout());
mainPanel.setBorder(new EmptyBorder(5, 5, 5, 5));
JPanel listPanel = new JPanel(new GridLayout(0, 2, 10, 0));
JPanel leftListPanel = new JPanel(new BorderLayout(0, 10));
JLabel leftLabel = new JLabel("Left value:");
JTextArea leftTextArea = new JTextArea("Hello Hello Hello\nTesting!\ntest");
JScrollPane leftScrollPane = new JScrollPane(leftTextArea);
leftListPanel.add(leftLabel, BorderLayout.NORTH);
leftListPanel.add(leftScrollPane, BorderLayout.CENTER);
JPanel rightListPanel = new JPanel(new BorderLayout(0, 10));
JLabel rightLabel = new JLabel("Right value:");
JTextArea rightTextArea = new JTextArea("Hello Hello Hello\nTesting!\ntest");
JScrollPane rightScrollPane = new JScrollPane(rightTextArea);
rightListPanel.add(rightLabel, BorderLayout.NORTH);
rightListPanel.add(rightScrollPane, BorderLayout.CENTER);
listPanel.add(leftListPanel);
listPanel.add(rightListPanel);
mainPanel.add(listPanel, BorderLayout.CENTER);
JPanel buttonsPanel = new JPanel(new BorderLayout());
buttonsPanel.setBorder(new EmptyBorder(10, 10, 10, 10));
buttonsPanel.add(new JButton("Do something"), BorderLayout.WEST);
buttonsPanel.add(new JButton("Do something different"), BorderLayout.CENTER);
buttonsPanel.add(new JButton("Do something even more different"), BorderLayout.EAST);
mainPanel.add(buttonsPanel, BorderLayout.SOUTH);
jFrame.setContentPane(mainPanel);
jFrame.pack();
jFrame.setVisible(true);
}
}
Explanation:
Firstly I created a main JPanel with a BorderLayout. This JPanel will be split horizontally, the CENTRE component will be another JPanel containing the text areas and labels, and the SOUTH component will be a JPanel containing the buttons.
The JPanel that contains the text areas is given a GridLayout so that it can be easily split vertically, and is also given a hgap of 10 to add some spacing.
The left and right JPanels that are put into that are both the same. They have a BorderLayout with a vgap to add spacing. The NORTH component is a JLabel and the CENTRE component is a JScrollPane containing a JTextArea.
Finally, the SOUTH component of the main JPanel is another JPanel which is given a BorderLayout again. Three JButtons are added with WEST, CENTRE and EAST attributes allocated accordingly.
The overall result looks like:
Here is your code with just some little changes :)
import java.awt.*;
import javax.swing.*;
public class GUITest extends JFrame {
public GUITest() {
super("Testing Title");
Container pane = getContentPane();
pane.setLayout(new BorderLayout());//Modified Layout to BorderLayout
pane.add(getHeader(),BorderLayout.NORTH); //BorderLayout.NORTH
pane.add(getTextArea(),BorderLayout.CENTER);//BorderLayout.CENTER
pane.add(getButtonPanel(),BorderLayout.SOUTH);//BorderLayout.SOUTH
}
public JComponent getHeader() {
JPanel labelPanel = new JPanel();
labelPanel.setLayout(new GridLayout(1,2));
labelPanel.setSize(getPreferredSize());
JLabel labelLocal = new JLabel("Left value: ", JLabel.CENTER);
JLabel labelDB = new JLabel("Right value: ", JLabel.CENTER);
labelPanel.add(labelLocal);
labelPanel.add(labelDB);
return labelPanel;
}
public JComponent getTextArea() {
JPanel textPanel = new JPanel();
textPanel.setLayout(new GridLayout(1,2,5,0));
JTextArea testTextArea = new JTextArea();
testTextArea.setEditable(false);
JScrollPane sp1 = new JScrollPane(testTextArea);
JTextArea testTextArea2 = new JTextArea();
JScrollPane sp2 = new JScrollPane(testTextArea2);
testTextArea2.setEditable(false);
testTextArea.setText("Hello Hello Hello\nTesting!\ntesterino\ntesteroni");
testTextArea2.setText("Hello Hello Hello\nTesting!\ntest\nABC123\ncdef123\nhijk123");
textPanel.add(sp1);
textPanel.add(sp2);
return textPanel;
}
public JComponent getButtonPanel() {
JPanel inner = new JPanel();
inner.setLayout(new FlowLayout());//Modified to standard FlowLayout
inner.add(new JButton("Do something"));
inner.add(new JButton("Do something different"));
inner.add(new JButton("Do something even more different"));
return inner;
}
public static void main(String[] args) {
GUITest e = new GUITest();
e.pack(); //Modified setSize(700,500) to pack()
e.setVisible(true);
e.setResizable(false);
e.setDefaultCloseOperation(EXIT_ON_CLOSE);
e.setLocationRelativeTo(null);
}
}
GridLayout sizes all cells the same, i.e. your outer layout with 3 rows and 1 column makes 3 cells of all the same size.
Instead, use BorderLayout for your outer container and add the top, mid and lower panels with constraints BorderLayout.NORTH, BorderLayout.CENTER and BorderLayout.SOUTH respectively
I looked on many questions and websites but I can not find the answer.
I have a JPanel. I would like to add a scroll bar, so I thought I would use a Jscrollpane.
public class TheFrame extends JFrame {
public ThePanel canvas;
public TheFrame() {
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setLayout(new BorderLayout());
//-------------------------------------
JScrollPane scroll = new JScrollPane(canvas);
scroll.setViewportBorder(new LineBorder(Color.RED));
scroll.setHorizontalScrollBarPolicy(JScrollPane.HORIZONTAL_SCROLLBAR_ALWAYS);
add(scroll, BorderLayout.SOUTH);
//-------------------------------------------------
canvas = new ThePanel();
setSize(700, 400);
this.add(canvas, BorderLayout.CENTER);
setVisible(true);
}
At the moment, the scroll is just appearing at the bottom. The border shows that it is only a small area at the bottom. I am trying to put the Jpanel into a Jscrollpane. So the border is around the whole application area. ThePanel extends JPanel. Thank you for any assistance.
JScrollPane scroll = new JScrollPane(canvas);
add(scroll, BorderLayout.SOUTH);
canvas = new ThePanel();
this.add(canvas, BorderLayout.CENTER);
A couple of problems:
the canvas variable is null when you create the scrollpane to nothing is added to the scrollpane
a component can only have a single parent so when you add the canvas to the "CENTER" you remove it from the scrollpane.
The structure of the code should be:
canvas = new ThePanel();
JScrollPane scrollPane = new JScrollPane( canvas );
add(scrollPane, BorderLayout.CENTER);
setVisible( true );
That is, you add the canvas to the scrollpane and the scrollpane to the frame.
Add canvas to scroll, and add scroll to this. JScrollPane wraps the component, it doesn't magically add itself to the component.
Example:
JFrame frame = new JFrame();
JPanel pane = new JPanel();
JScrollPane scroller = new JScrollPane(pane);
frame.add(BorderLayout.CENTER, scroller);
scroller.setWheelScrollingEnabled(true);
scroller.setHorizontalScrollBarPolicy(ScrollPaneConstants.HORIZONTAL_SCROLLBAR_NEVER);
scroller.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS);
frame.setVisible(true);
I would like the following lay out...
JButtons on top along side eachother.
The JTextArea should be under the buttons.
The JTextArea should also have a scrollbar.
...for the code below.
JPanel jp = new JPanel();
One = new JButton("One");
Two = new JButton("Two");
TestOutput = new JTextArea();
jp.add(One);
jp.add(Two);
jp.add(TestOutput);
Use a nested layout: To a JPanel having BorderLayout,
add a JPanel having FlowLayout for the buttons to the NORTH
and a JScrollPane for the JTextArea to the CENTER.
The keyword is layering - having JPanel on JPanel.
Use a GridBagLayout
See this for more help : How to Use GridBagLayout
Now note that the JTextarea to have a scrollbar have nothing to do with layouts.
See this for more help in that context : How to Use Scroll Panes
The FlowLayout in a JPanel for the JButton instances is one way to go. You might also use a JToolBar for the buttons.
import java.awt.*;
import javax.swing.*;
class ButtonsAndTextAreaLayout {
ButtonsAndTextAreaLayout() {
JPanel gui = new JPanel(new BorderLayout(5,5));
// use a toolbar for the buttons
JToolBar tools = new JToolBar();
// use firstWordLowerCase for attribute/method names.
JButton one = new JButton("One");
JButton two = new JButton("Two");
tools.add(one);
tools.add(two);
// provide hints as to how large the text area should be
JTextArea testOutput = new JTextArea(5,20);
gui.add(tools, BorderLayout.NORTH);
gui.add(new JScrollPane(testOutput), BorderLayout.CENTER);
JOptionPane.showMessageDialog(null, gui);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
new ButtonsAndTextAreaLayout();
}
});
}
}
You can either use a GridBagLayout as suggested, or nest multiple layout managers such as:
JFrame frame = new JFrame();
frame.setLayout(new BorderLayout());
JPanel buttonPanel = new JPanel();
JButton oneButton = new JButton("One");
JButton twoButton = new JButton("Two");
buttonPanel.add(oneButton);
buttonPanel.add(twoButton);
JTextArea output = new JTextArea();
JScrollPane scrollPane = new JScrollPane(output);
frame.add(buttonPanel, BorderLayout.NORTH);
frame.add(scrollPane);
frame.pack();
frame.setVisible(true);
I have a JTextArea in a JPanel. How can I have the JTextArea fill the whole JPanel and resize when the JPanel resizes and scroll when too much text is typed in?
JPanel panel = new JPanel();
panel.setLayout(new BorderLayout()); //give your JPanel a BorderLayout
JTextArea text = new JTextArea();
JScrollPane scroll = new JScrollPane(text); //place the JTextArea in a scroll pane
panel.add(scroll, BorderLayout.CENTER); //add the JScrollPane to the panel
// CENTER will use up all available space
See http://download.oracle.com/javase/6/docs/api/javax/swing/JScrollPane.html or http://download.oracle.com/javase/tutorial/uiswing/components/scrollpane.html for more details on JScrollPane
Place the JTextArea inside of a JScrollPane, and place that into the JPanel with with a layout that fixes the size. An example with a GridBagLayout, for instance could look like this:
JPanel panel = new JPanel();
panel.setLayout(new GridBagLayout());
JScrollPane scrollpane = new JScrollPane();
GridBagConstraints cons = new GridBagContraints();
cons.weightx = 1.0;
cons.weighty = 1.0;
panel.add(scrollPane, cons);
JTextArea textArea = new JTextArea();
scrollPane.add(textArea);
This is only a rough sketch, but it should illustrate how to do it.