So, first you selected it and it does the things I told it to do, and then you deselected it, wanting to start an event, but only when it first has been selected.
Add an ItemListener to the radio button.
Read the section from the Swing tutorial on How to Write an ItemListener for more information.
and then you deselected it, wanting to start an event, but only when it first has been selected.
Well, the only way you will get the unselected event is if it has been selected first.
Related
I have two radio buttons, both added to a ButtonGroup. I have added an ActionListener for both. Suppose that at present the first radio button is selected, then again if I click on the same button then again actionPerformed() will be called. It doesn't look good. I want to prevent the call to actionPerformed() if that radio button is already selected.
One possible way could be to store current selected radio button state in a variable, but I want to know the java internal method for this.
Is there any method to do this?
if(radioButton.isSelected()) this will tell you if its selected. if it's selected you don't perform action. If it's not selected perform the action.
I have a JToggleButton, not in a group, and if it's pressed, I want to be able to Un-Select
it if I press another JButton.
I've tried using:
toggleButton.setSelected(false);
toggleButton.doClick();
but neither un-Select the toggle button, it stays "highlighted".
What can I do so that the toggle button goes back to the normal
un-Selected state, like if I pressed it again?
Is it a matter of calling the above while in the UI Thread?
jToggleButton.doClick(): Programmatically perform a "click". This does the same thing as if the user had pressed and released the button.
jToggleButton1.setSelected(false);
jToggleButton1.doClick();
If you execute this code subsequently, it is actually doing nothing. Because, as soon as the first line set the jToggleButton1 as unselected second line set it as selected. If you want just jToggleButton to be unselected use jToggleButton1.setSelected(false) by removing doClick(). But if you want to toggle among selected and deselected using your other JButton click, use jToggleButton1.doClick() only.
My program has the ability to change the selected item of my combobox. But how can I know if the item change has been caused by an human mouse click on the item itself or by my program.
I'm pretty much looking for a MouseListener that can be added to the items of the JComboBox and not the JComboBox itself.
A JComboBox is a compound component, and it is highly recommended that you avoid using low-level listeners such as a MouseListener with it. Instead why don't you disable your selection listener (perhaps you're using an ActionListener) when the code selects an item, and then re-enable it after the selection is done. Thus you'll know that any activity by the ActionListener is from a user's choice. You can disable and enable the listener by either removing and re-adding it, or by giving using a boolean variable that allows the listener to react only when the boolean is true.
This is the scenario:
I have a JTable of nxn. In the Col(0) of each cell, have a slider with two thumbs each for min and max,two JTextField to represent min and max.
Whenever i click for first time on the cell, slider doesn't responds but on the second click the slider responds.
My guess is that on the first click the JTable gets the focus and on the second click the cell.
would like the cell to respond on the first click.
Thank you on advance...
set setClickCountToStart(1), more descriptions here
As I didn't see your code, I guess it's the FocusTraTraversalPolicy that is causing your problem.
In each container of Swing, the components have a predefined order of getting focus. They get the focus in order when you press the Tab button on the keyboard. So when you first click a container, there's a default component that gets the focus, if you're not satisfied with it, you can use the FocusTraversalPolicy to modify it.
Check this lnk out, it may help you.
I have a JTextPane sitting in a JFrame, with a popup menu that is assigned to the JTextPane through the JTextPane.setComponentPopupMenu method.
I want to give the JTextPane a "Word-like" popup behavior. By that I mean, if you right click outside of your current text selection, the caret will reposition to where you right clicked, with menu options that affect a text selection (such as cut, copy, or bold) disabled. If you right click within your current text selection, the popup will appear with options that effect text selection enabled, the text selection will persist, and the caret will not move.
The problem is I cannot seem to find where I can put the code that handles the selection change. I tried:
Using the "PopupMenuWillBecomeVisible" event which is triggered before a popup becomes visible. The event passed into this method does not contain any mouse event information so there is no way for me to use viewtomodel to find out how to modify the selection. I could use MouseInfo but that seems dubious at best.
Using MousePressed/MouseReleased events in the JTextPane or JFrame. Apparently, neither of these events are invoked when a popup menu is triggered. In fact, I still can't determine what the parent component of my popup menu is. (I did read that in windows "MouseReleased" is the popup trigger, while in other systems "MousePressed" is the trigger. I tried both and neither worked).
So, I guess the problem is that I can't seem to find a place to put code where it would be called before the popup menu becomes visible, but has awareness of the mouseEvent that triggered the popup menu. I must be missing something here.
with a popup menu that is assigned to the JTextPane through the JTextPane.setComponentPopupMenu method.
You can use the older approach of displaying the popup based on your own custom MouseListener.
See the section from the Swing tutorial on Bringing Up a Popup Menu. Now you have access to the MouseEvent so you can convert that point to a point in the Document so you know where the click was made, on selected or unselected text.