I'm going to make an application (in Swing) that uses a tree to visualize a data structure (JTree). A tree will be on the left side of a window. The user will be able to browse a tree. The parameters of every tree node will be displayed on the right side of the window.
The example windows will be looking like this
===========================
| tree panel | data panel |
| | |
| | |
| | |
---------------------------
The problem arises when a user wants to change that data. when should I validate them ?
The easy approach is to open a new modal dialog (JDialog) and let the user to change this data in it. Validation of data would take place in an "ok" button listener method but this is a little clunky. I would like to allow the user to edit those data right in the data panel. In that case when should I validate them?
Is there a pattern of such solution in Swing?
Or any online tutorial how to do it?
Thanks in advance.
Dialogs are bad.
Immediately discard any complete nonsense input immediately. For instance, typing a letter in the numerical field (use Document filters). Don't beep. Don't require any particular commit step. You may have retain partially entered data.
I'm not totally sure what you're after, but..
You could maybe add this "ok" button (or "commit changes" or whatever) to data panel and when the button would be pressed, you would validate the data and save the changes if the changes are valid?
(So you'd have editable components at the data panel)
Edit: if this wasn't good, could you clarify me a bit:
Is the data panel showing data for one item of the tree at time?
What kind of data is there to change (and to validate)
Anyway, if you want to validate straight the changes made to an edit component (for example JTextField), you can use for example
Formatted text fields, see How to Use Formatted Text Fields
For more general validating, see InputVerifier
More ideas, see Validating Numerical Input in a JTextField (concentrates of numerical input but usable for other purposes also)
Related
I have a large set of data from which the user has to select one. I'm thinking of a way to implement it (of course, in a GUI). I have a few ideas. But just thought of posting here as there may be better alternatives..
Say, user has to select a name from a large set of user base. If I simply put a text field for user to enter the name, then there can be issues like entering same name in different formats, misspelling etc...
I see two options here
Using a combo box
Using a list (Actually i'm thinking of something like a tool tip. As I cant show the whole list always due to space issues)
But combo box won't be much user friendly i guess. As the user will have to scroll around the whole list to select an entry. If the number of entries are too large, this will be
Which means, now I'm left only one option. A popping up list, which will change the content according the text user is entering in the text field. So he can type first few letters and the list will show all the entries starting from the entered text. Got my point, right?
Are there any other better to achieve this kind of need?
If I'm going to implement above, what will be the best way to follow. I'm thinking of extending the JTextField to add required functionality. Well, I'll put some method to set the popup list entries. And I'll add some actionListner to watch the text field, and control the popup list accordingly...
Autocomplete is what you are probably looking for. Google for "java swing jcombobox autocomplete" and limit results for the last couple of years to get relevant results. There will be a lot of examples and ideas on how to implement this with custom code.
I believe there is also some custom libraries like "swingx" that provide at least partial or full implementations to save time.
http://swingx.java.net/
They have released code as recently as the beginning of this years so it appears active and might have what you need.
You could take a look at SwingLab's autocomplete feature, it allows you to attach it to a JCombBox, JList or JTextComponent
use AutoComplete JComboBox/JTextField
based on Standard Java Classes
no issue with larger sets of data
no issue with Focus, BackSpace Key, Caret
for better performance to required sort the array before use
simple workaround for setStrict(true/false), restrict input to array
I'm new to GWT. I have a simple SuggestBox which is populated using a MultiWordSuggestOracle. Users input their data to this SuggestBox, and if they find any match with the existing Suggestions its well and good. I'm able to retrieve this value in the SelectionHandler code as below.
display.getSuggestBox().addSelectionHandler(new SelectionHandler<Suggestion>() {
public void onSelection(SelectionEvent<Suggestion> event) {
String selectedProperty = ((SuggestBox)event.getSource()).getValue();
// do something with the property value
}
});
But users are allowed to enter values which are not already in the Suggestion oracle, in which case I should read this value and do something with this,may be saving to db as a new data.(The thing which I'm looking for is something like a browsers navigation widget where we show suggestions, users can pick up any suggestion or he can type in his new entry and carry on.) What I needed is a way to retrieve this new text user has entered? Data will be read on a button click. What I tried out is this.
display.getSaveBtn().addClickHandler(new ClickHandler() {
public void onClick(ClickEvent event) {
String selectedProperty = display.getSuggestBox().getValue();
//String selectedProperty2 = display.getSuggestBox().getText();
// Blank in both cases :(
// tried display.getSuggestBox().getTextBox().getValue(),but blank again
}
});
I tried to employ onChange() event handlers (as shown below)
display.getSuggestBox().addValueChangeHandler(new ValueChangeHandler<String>() {
public void onValueChange(ValueChangeEvent<String> event) {
String selectedProperty = ((SuggestBox)event.getSource()).getValue();
Window.alert("on change -- "+selectedProperty);
}
});
This is working fine except one scenario. Suppose there are two suggestions in the oracle,say 'createTicketWsdl' and 'createTicketTimeout'. When the user types in 'cr', he is opted with these two options, and if he selects 'createTicketWsdl' by pressing keyboard ENTER, then my alert is printing 'createTicketWsdl' which is correct. But if he selects 'createTicketWsdl' using mouse, then my alert is printing 'cr' (I tried to post the screenshot to give a better understanding, but being a new user I'm not allowed).(which I wanted to get as 'createTicketWsdl'since thats what he has selected). Soon after printing my alert, the value in the SuggestBox changes to 'createTicketWsdl'.
Is there a way to retrieve the value of the suggest box? I saw a similiar thread GWT SuggestBox + ListBox Widget, where some source code for a custom widget is available. But I didn't take the pain of trying out that, since what I want is simply get the current value from the SuggestBox and I hope there should be some easy way.
Thanks for all your help!
Your question is not very clear. You need to clarify your language a lil' bit. For example - is the following a question or an assertion? I mean, it sounds like an assertion but it has a question mark.
What I needed is a way to retrieve this new text user has entered?
Also, I do not understand what you mean by "he is opted by". Did you mean to say, "he is presented with the options ..." ?
Therefore, I am guessing your situation.
You have a listbox of existing items.
You have a textbox which allows freeform text entry
Any items whose prefix values matches the current textbox entry, the listbox items would be filtered to be limited to the matching items.
Even if the current textbox entry presents matching prefixes to filtering the listbox, the user can still perform freeform text entry. So, there are two possible cases here
4.1 the user clicks on the list box to select one of the filtered items
4.2 the user press enter key, which triggers selection of the current value of the textbox.
However, you find your widget participating in a race condition, so that when you click on the widget, the ValueChangeHandler gets triggered rather than the SelectionHandler. I do not know the structure of your widget so that is my best guess.
The problem is that you are allowing two separate modes of obtaining an outcome and you probably did not have well-defined state machine to handle choosing the appropriate mode. One mode is by the textbox and the other is by selection on the listbox - and you do not have a well-defined way of which would mode would be effective at any moment.
If my guess is accurate, this is what you need to do:
You must restrict your outcome to coming from only the textbox.
Your listbox selection must not trigger any outcome. Any change in listbox selection must propagate back to the textbox - to allow the user the chance of making further freeform entry based on that value.
only the keyboard enter on the textbox will trigger the final outcome.
I am writing a Java application for digitizing a group of documents in the office that I am working in and I am wanting to check if 5 textfields are populated and 4 combobox fields as well before the save button is enabled (I have it checking if i press a button (that happily says "Check"), but i would much rather have it auto-check to see if they are populated or if they are null).
If it makes a difference i am using NetBeans for this project.
Basically I need the fields to have something in them before the document can be saved.
Any and all help will be greatly appreciated as this is the final step in creating this application... :D
Thanks,
Erik
There are two ways (I can think of):
1- Put a listener on each field, this listener will be triggered when the field is populated. Inside the listener increment a counter for example, or set a flag. If all flags are set or if the counter reaches (9 in your example) then enable the button.
2- Enable the Save button, but call a validate() method before doing the Save action. Any unpopulated field will have a red mark beside it (shown by validating) like in web applications.
I'm writing my 1st Java program (in Netbeans) and I'm lost. I have 2 questions at the moment, if anyone is kind enough to help me.
Here's what the program is supposed to do:
take 1 of 4 "status" options, plus a 5 digit number (both of these items are entered by a user via a touch-screen monitor) and then email this info to someone with the subject line of: "Item #[5 digit number from JFormattedTextField] is currently [1 of 4 possible status options].
Email command would command after user clicks "enter" button, and then user clicks "OK" on a pop-up which asks user to confirm message about to be emailed. As far as my 3rd question, it's about the e-mailing part, and I figured that would be a another thread after I get this button & text field stuff ironed out.
Here's a picture of the touch screen UI I have so far:
(can't post images as a rookie, go to krisbunda.com/gui.png for this image)
Question #1:
the 4 status options (4 JButtons) are wrapped inside of a JPanel. I want the most recent button to have been pushed in the "statusPanel" JPanel to change the background to blue and the button text to white.
Can I put a mouselistener on the button's parent JPanel to listen for click events on the children (the 4 status JButtons), and then whichever button was last clicked, it will turn blue w/ white text? Please point me in the right direction.
Question #2:
I have a JFormattedTextField named "display" that shows the numbers as they're clicked, which are appended from a StringBuffer named "current". I want the text field to only accept a total of 5 numbers.
When I tried putting a mask of "#####" on the field, it would only chime a warning beep when I pushed the number pad's buttons. Currently I've chosen "Category: number" and "Format: custom" and then typed "#####" in the "Format:" field. This allows me to click number buttons and see their text displayed, but it doesn't stop me from typing more than 5 characters.
I'm doing this through the "Properties> FormatterFactory" dialog box. A screen shot is shown below:
(go to krisbunda.com/text-formatterFactory.png to view this image)
And here's the code I have so far:
(my post was too long with this code, so go to: krisbunda.com/java-sampleCode.txt to view)
Thanks in advance for any help!
Your code looks fine, and you already have fields set up to hold references to all your buttons, so now you just need to write the code inside the status setting buttons and then make them call a subroutine with the new status. This subroutine should then reset all the buttons to their default color and then set the special selected color on the button that corresponds to the new or existing status.
Edit: adding code here in response to your comment...
Firstly, never use == with Strings. You MUST use equals() otherwise when you get two Strings that are identical, but are different objects, they will not be the same and your comparisons will fail.
There are much better ways of coding this up, including using enums etc. but this should work for you:
// Reset all the buttons
outsideNotReadyButton.setBackground(...);
loadedButton.setBackground(...);
outsideReadyButton.setBackground(...);
shippedButton.setBackground(...);
// Now set the one of the button's colors conditionally
String status = ...
if(status.equals("SHIPPED")) {shippedButton.setBackground(Color.BLUE);}
else if(status.equals("LOADED")) {loadedButton.setBackground(Color.BLUE);}
// ...and so on
An ActionListener is the more common approach to buttons, as discussed in How to Use Buttons, etc. A FocusListener, also used in this example, is one way to change a button's appearance in the way you describe.
An sscce showing just your JFormattedTextField problem will be more helpful. Several such examples may be found in the article How to Use Formatted Text Fields.
I have a JCheckBox that should not be checked by the user when a certain other field is empty.
So now I want to have an error popup and then reset the checkbox (I've considered disabling the checkbox, but the connection to the other field is non-obvious, and a tooltip text IMO not visible enough).
What's the correct way to do that in Swing? Through a PropertyVetoException? Where do I throw it and where do I catch it? My first (probably ugly) idea would be to add a ChangeListener that itself shows the popup and resets the value.
Edit: The question is about Nikki (screenshot below), an app I am developing which geotags images and exports them to Google Earth's KMZ format. The checkbox is used to select the images to include in the export. But this requires the images to be gotagged first (which in turn requires either a timestamp, or manual assignment). I don't think this requirement can be made obvious through the UI layout.
(source: brazzy.de)
I would simply disable the check box and add a message explaining why the option is not available. A nice way to show the message is to display a mini exclamation mark next to the check box and put the message in a tooltip.
Poping up an exception often feels wrong because users don't read error messages. For most users an error message popup means that the application did something wrong, in your case it's the normal behavior.
Edit if you insist on letting the check box enabled, another way to show the user that some info is missing would be to flash the missing data. Eg. if latitude and longitude are missing and the user clicks on export, set a red background onto these fields for a just a second. This will clearly show the user what's missing.
In this screen, don't you want to put the mouse over the red circle to understand what's going on?
validation http://www.vogella.de/articles/EclipseDataBinding/images/validation10.gif
I don't think the Export JCheckBox should be disabled at all. Instead, the Export JButton itself should examine the current export list and display any anomalous entries in a way that allows navigation to a chosen photograph. If all entries are correct, Export would proceed as usual.
Addendum: It think you are right to keep the interface as non-modal as possible. My model for this would be unsaved files when exiting an editor or uncommitted changes when closing a project in an IDE.
If that's a status line at the bottom of the window, you might indicate the number of photographs currently selected for export, adding a count if any still need geocoding.
The field should simply be allowed to disable the checkbox. If the coupling is unintuitive then the GUI layout may have to be reconsidered.
EDIT: I ran it from your page, and I believe the issue here is that you actually have a third and fourth step in addition to select folder, select images. The third step is validate image, and fourth is select images for export. I think your problem is that this is not clearly conveyed in the current layout, and that reflects in your question.
I would suggest that you create a separate column containing the checkbox for each image, and that THAT checkbox is disabled until the image passes validation (step 3). Perhaps with an explanatory text in the column about why the image hasn't passed yet.