I want to realise a GUI in java that contains columns and lines and the button "check", the goal is to check if the value of a column match with criterion.
the columns represents the names of a data file columns, and the lines represents criteria ( I want to list them in a properties file ). can you give me an example how I can do that.
Here is the main GUI widget toolkits existing in the Java world:
AWT/Swing, the old way, a pur java solution which works everywhere,
JavaFX, tends to be a replacement for Swing, part of the JRE since Java7,
SWT, use of natives functions, so the rendering is really quicker, but it may be more complicated than the two above.
About AWT/Swing, you should start by take a look at some tutorials. Then, here is the main classes you would use:
You need a check button: JCheckBox
Colums and lines ? JTable, mainly because you can extend an AbstractTableModel and easily fit the properties file. Moreover, you can save the model thanks to an ObjectOutputStream: your users will be happy to be able to save their works.
Once you start coding, feel free to ask a new question about your troubles :)
Related
I'm currently working on a client-server project where the client sends a request to the server and the server runs a database statement based on the information from the client. As there's no static length for the output I add all the data to a ArrayList<String> and send it back to the client.
The data that the client requests has a certain hierarchy so that one could also display it using an XML file (however the output to a GUI is wanted here instead of file creation). There's several ways of displaying I came up with. One would be using a simple text area, however using this, I need to do applying the layout myself and the option of folding where I can expand and collapse certain items is not possible.
Another possibility of course would be using a simple JList, however I read on Stackoverflow that using a JList to display hierarchical things is way easier done using a JTree.
When I decided trying to implement JTree I also found the Genealogy.java file provided by Oracle in their documentation of JTree. As to be seen in the first examples of this documentation there is always a filestructure being displayed and hence also a filestructure kind of representation (using folder- and file-symbols) is shown. In contrast to this Genealogy.java only shows the names of the persons so I tried to adapt the implementation from Genealogy.java to my case however I'm completely clueless of how to do this as I don't even know where these symbols come from and where I could possibly disable them and also don't really get what some of the methods I need to implement do.
As I'm currently really clueless of how to possibly accomplish that I really need some detailed help (only telling me to come up with my own implementation of JTree or TreeNode doesn't really help me at this point). Is there any simpler way or is the need to implement any of the before mentioned interfaces inevitable and if so, how would it be done?
EDIT:
This is how it currently would be displayed (example taken from the Oracle documentation, showing folder- and file-symbols in front of the string):
And this is how I want it to be displayed (also from the documentation, this time only displaying a string as node):
The answer almost certainly will be found via the (icon of the) TreeCellRenderer used for the tree nodes. See the File Browser GUI for tips. It shows how to set the icons in the FileTreeCellRenderer. Admittedly the point here is almost exactly opposite what it was there, but it still comes down to the same thing - the icons.
The section of the tutorial that covers it is How to Use Trees: Customizing a Tree's Display.
I was working on creating a weather application in Java using Weather Underground and I found that it does have data for some cities.
Initially, I was planning on using GeopIP to get the user's location automatically but since the support for cities is limited I decided to let the user choose the city every time the program starts.
I want the user to be able to choose a city from one that is supported by Weather Underground. The user will enter the name and as he/she enters the name, the possible locations will be displayed in a way similar to the one shown in the picture.
My question is:
How do I implement this search feature ?
My initial guess was to create a Vector containing all the names of the cities and then use brute force to find the match and display in a JPopup or a JWindow containing a JList but I guess there has to be a better method
Rephrase:
What I do not understand is WHAT INFO do I keep in the data structure I must use ? Should I manually create a list of cities that Weather Underground supports or is there another way to do it ?
Take a look at the Trie data structure (also known as digital tree or prefix tree). Autocompletion is one of the most common examples of it's usefulness.
The following article has a nice an very approachable explanation:
Roll your own autocomplete solution using Tries.
if you google autosuggestcombobox you will get some interesting results:
This one is written in JavaFX - I have used and extended it myself already. It is quite useful. What you get "for free" with JavaFX: a context menu with right-mouse click which is auto-generated containing some of the usual "stuff", like cut, copy & paste and even undo! So, I can recommend that solution. To get into JavaFX isn't so hard - and I think it is much easier to learn than Swing - and looks so much cooler! However this implementation has some drawbacks - especially when the layout is not left-aligned, because it is simply a text field on top of a combobox.
OK - but if you want to stick to Swing - you could probably use this one. I haven't used that myself, but the code looks quite straightforward and pretty clean - cleaner than the implementation for JavaFX I must admit (but that had some nice features). So - maybe you try - and extend it? It is built simply on JComboBox.
Scenario
I'm working with a Java model built from scratch in Eclipse. What's important in this model is that we save our output to MATLAB (.mat) files. I constantly add new features, which require new fields that in turn will have to be exported to the .mat file at every iteration. Upon restarting a crashed simulation, I might have to import the .mat file. To export or import my .mat file I use JMatIO.
For example, if I would add a new field rho_m (a simple double) to my class CModel, I have to add to my Save() method:
mlModel.setField("rho_m", new MLDouble(null, new double[] {rho_m}, 1));
And to my Load() method:
rho_m = ((MLDouble)mlModel.getField("rho_m")).getReal(0);
Note that even though rho_m is a double, it needs to be treated as a double[] in JMatIO. This probably has something to do with MATLAB being orientated towards matrices and matrix operations.
Problem
Instead of doing this manually (prone to errors, annoying to maintain) I would like to automate this procedure. Ideally, I would like my IDE to detect all the fields in CModel and write the code based on the field's name and type. Is there any way to do this in Java/Eclipse?
Ideas so far
I have no formal training in low-level programming languages (yes, Java is low-level to me) and am still relatively new to Java. I do have some experience with MATLAB. In MATLAB I think I could use eval() and fieldnames() in a for loop to do what I mentioned. My last resort is to copy-paste the Java code to MATLAB and from there generate the code using a huge, ugly script. Every time I want to make changes to the model I'd rerun the MATLAB script.
Besides that idea I've found terms like UML, but do not have the background knowledge to figure out if this is what I'm looking for or not.
Any help, even if it's just a small push in the right direction, is greatly appreciated. Let me know if I need to further clarify anything.
Looking at your scenario, you are doing model-driven code generation, that is, you have a model and want to get some code generated according to your current model. Therefore, you need a model-driven code generator.
I lead the ABSE/AtomWeaver project, so I'll outline what you can do to get what you want using AtomWeaver (There are however other solutions like MetaEdit+, XText or Eclipse's own GMT/EMF sub-system).
AtomWeaver is an IDE where you can build a model and generate code from that model. You can change your model as many times you want and hit the "Generate" button to get an updated version of your code. ABSE is the name of the modeling method.
We don't need to go into details, but essentially ABSE follows a "building-block" approach. You create a Template that represents a feature or concept of your model. Then, you can associate a mini-code generator just to that concept. You can then "instantiate" and combine those building blocks to quickly build your models. Variables increase the flexibility of your models.
You can also change your models, or add new features ("blocks") and generate again. The generators are built using the Lua programming language, a very simple language with C-Like syntax.
The best way to understand the ABSE development method and the AtomWeaver IDE is to download the IDE and see the samples or try the tutorials. And yes, you can use AtomWeaver for free.
I'm building on top of an existing UI which is in Swing. I need to add a search module wherein the user can enter search terms which should be auto-complete'd.
I'm considering building a UI very similar to Stackoverflow's 'tagging a question' feature. So in my use case each 'tag' would be a search term.
I'm completely new to Swing or UIs in general and have very little clue on how to start.
Any advice/pointers on how and where to start would be of great value to me.
there are two ways
exactly same way is implemeting Filtering for JTable (there started after 2nd or 3rd chars typed)
of use AutoComplete JComboBox / JTextField
You should use and ArrayList where every time someone types a keyword into the search box and clicks find, the program goes in a while loop and searches all topics with that particular tag. and hence can be displayed later as a list with found solutions.
I'm wandering myself what component is the best for displaying fast search results in swing. I want to create something like this, make a text field where user can enter some text, during his entering I'll improve in back end fast search on database, and I want to show data bellow the text box, and he will be able to browse the results and on pres enter result will be displayed in table. So my question is is there any component which already have this logic for displaying?
Or is it's not, what is the best way to implement that.
This search will be something what ajax gives me on web, same logic same look and feel, if it's possible on desktop application.
Are you looking for something like an AutoComplete component for Java Swing?
SwingX has such a component. See here for the JavaDoc. It has a lot of utility methods to do various things, i.e. auto-completing a text box from the contents of a JList.
I strongly, strongly recommend that you take a look at Glazed Lists - this is one of the finer open source Java libraries out there, and it makes the bulk of what you are asking about super easy.
You will have to first attach a listener to the JTextFields Document to be notified whenever the user types in the field (or changes it).
From there, you can fire off any server-side code you need. The results of that can be used to update a listbox.
A few things to keep in mind:
The code to do the search against the backend must be in another thread
The code that updates the list box should update the list box's model
You will need to manage all your backend search results so that you only update the listbox with the most recent result (e.g. user types 'A', backenf searches for that. Meanwhile, user has typed 'C', kicking off a backend search for 'AC'. You need to ensure the results from the 'A' search dont' make it to the listbox if the 'AC' search results are available).
Use Hibernate Search.
The SwingHack (http://oreilly.com/catalog/9780596009076/) book has an example of this.
In the interest of killing two birds with one stone: have a separate indexing thread. This will:
Improve the speed of searches whenever they are executed.
Improve the responsiveness of the UI since indexing is happening in a separate thread.
Of course, exactly how you perform the indexing will vary widely depending on your particular application. Here is a good place to start researching: Search Indexing. And please, ignore the reference to Web 3.0 [sic].
It is possible of course. It is simple too. For drop down list of terms just use popup menu. This is simple. The background processing of entered text is simple too. Enjoy!