I'm developing a custom table component for very large and very custom content. Therefore I decided not to go with TableView, but start from scratch (i.e. Control). I adopted the idea of the VirtualFlow to create and manage only the visible part of the table and reuse cells that have become invisible. However I needed virtual rows and columns.
My CustomVirtualFlow implements layoutChildren(). From the component's size and scrollbar positions I know which cells are visible. If necessary, I add cells to the VirtualFlow. I then update the content and css pseudo class states (selected, focused, ...).
This works almost fine ... currently, my only problem is that the css styles are sometimes lagging: newly created cells are shown with e.g. wrong backgrounds for a moment and then get correcteted with the next pulse.
My explanation for this is that JavaFX performs layout in two passes:
first a css pass and secondly the layout pass that calls layoutChildren().
The css of newly added children (during layoutChildren) is therefore not processes correctly.
I tried to call applyCss() directly, which helps, but seems to do too much because it takes a lot of time.
My question is:
How is the correct way to add nodes during layout, i.e. if the size of the component makes it neccessary to use further nodes?
If it is not during layoutChildren(), where else should I do it?
Color newColor = new Color(197,222,90);
JButton newButton;
newButton = new JButton(icon);
newButton.setBacgroundColor(newColor);
When it is pressed it changes color. How can I keep it from changing color? I have multiple buttons, so if there is solution in one or two rows please help me, and keep in mind that I'm beginner, writing some huge classes won't help me, because I have multiple buttons with different names to be affected with this.
EDIT: Solution in one line is:
UIManager.put("Button.select", newColor);
But it changes all button colors but I need another to have different a color.
EDIT2: After some research I figured out there isn't an easy solution (but it should be). How I see it I have 2 solutions, 1. is to break buttons to separate classes and set UIManager for them, and second is to make custom buttons. It is just too much work for button.
I've found nothing that can change that particular behavior on a normal JButton. The problem being, that whatever you write in your actionlistener for the button, will occur AFTER you've let go of the mousebutton, and not "while clicking".
There are workarounds, however.
My preferred choice is, to remove all graphics from the button, and then add your own images to the button's regular and pressed states. You could take a screenshot of your GUI, cut out the button, and set that image to be both states.
JButton myButton = new JButton();
// Sets button x, y, width, height. Make the size match the image.
myButton.setBounds(5, 30, 100, 30);
// Remove border-graphics.
myButton.setBorder(null);
// Remove default graphics from the button
myButton.setContentAreaFilled(false);
// Remove the focus-indicating dotted square when focused (optional)
myButton.setFocusPainted(false);
// Here, myImage is a simple BufferedImage object.
// You can set one like this, provided you have an "images" package,
// next to your main class (ex: com.somecompany.someprogram.images),
// that contains an image:
BufferedImage myImage = ImageIO.read(getClass().getResource("images/myImage.png"));
// Then we simply apply our image to both states for the button, and we're done.
myButton.setIcon(new ImageIcon(myImage));
myButton.setPressedIcon(new ImageIcon(myImage));
Obviously there are many ways to retain and load an image, but since that's not the issue here, I'll leave additional methods out of it.
There's no need to go through it all countless times, though. It should be pretty easy to write your own custom implementation of the JButton class, in which a custom constructor takes a single parameter, being the BufferedImage, and then the constructor sets it up accordingly (changes the icons). Then all you have to do when you create a new JButton, is to use your own class, and pass it an image:
JButton btn = new MyCustomJButton(myImage);
You could also easily get along with very few images. All you need is a HashMap which holds all the images, with a String as a key. Imagine you need 4 OK-buttons. You make a single image of a button with the text "OK" written on it. Then you put that image into the HashMap, like so:
myMap.put("OK", myImage);
Then you could do this when creating a button, over and over again if you'd like more:
JButton btn = new MyCustomJButton(myMap.get("OK"));
Alternatively:
Another way of achieving this, which is pretty elaborate, but probably considered "the right way", is to use ButtonUI, as presented in this answer to another post.
If the OP is referring to the temporary change of background colour on a button with an icon at the moment the mouse is pressed, the following statement does the trick:
button.setContentAreaFilled(false);
"If you wish to have a transparent button, such as an icon only button, for example, then you should set this to false."
This took me a long time to figure out. It seems to be a little known technique, perhaps since its name gives little clue as to its effect.
With only first lane we can still see that it is clicked. You need to combine those two:
button1.setContentAreaFilled(false);
button1.setEnabled(false);
and if you don't wanna in grey color you put another button under him.
panelname.add(button1,+5,+5); \\(first not clicable, not visible button, notice +5)
panelname.add(button2,-5,-5); \(-5,-5 means it is 5 points under panel)
i am new to GWT and GWTP and the question sounds stupid.. Can I make an abstract PresenterWidget or similiar?
Like in normal Java extending the "class" and reuse / extend the logic. But not only the class, the whole thing of View and Presenter. I try to explain my initial situation and maybe you have another idea.
The image hopefully helps to explain it. The "Main-Tab" and every other tab consists of a collection of views which have the same base structure and the same logic.
the base structure consists of
border around EVERYTHING
an image (the wwitch)
a title
a textarea
a PresenterWidget which is added to a contentSlot of the parent (the menu left)
and below the base are view specific components like buttons, text or any other widget. So a main part of the view with logic is repeading. If the switch is "toggled" the view is hidden (the textarea and any childs / view specific components) like the lowest view in the picture. Furthermore the PresenterWidget left changes the color.
The logic is working, but now I am searching a proper way to solve this without repeading code and the possibility to add child elements which are hidden as well by toggling the switch. Can I add to a PresenterWidget child widgets and define where there should be added? like: Even if this is possible, it feels a bit inconvenient.
Thanks in advance.
I just want to post the solution:
I have now a simple Composite (KPICommonView) for the switch, title and the description. It got another FlowPanel below the description, where the specific components will be added later. For this the Composite implements "HasWidgets" and overrides the "add(Widget w)"-method which is called by UiBinder if the Widget is added and has child elements.
<own:KPICommonView title="First Header" description="I am a happy description :)" anchorToken="{nameAnchors.getFirst}">
<g:Label>child component</g:Label>
</own:KPICommonView>
I am not sure if I do a PresenterWidget for every segment and every PresenterWidget has one of the KPICommonView added, or if I do one normal Presenter which adds more than one of the CommonViews.
The CommonView furhter creates the PresenterWidget for the menu item on the side. It gets the attributes from the constructor (anchorToken, title) and adds it to the slot (which happens ugly, because the View has hard coded the parent saved to call "addInSlot()". The repeading code for the switch is handled by the KPICommonView.
I have an application that use the MVVM pattern. In the main view model, I create a view and its viewmodel of another control.
I need to know the height of the control, but when I create the control, if I see the Height value of the control I get NaN.
I use this code in my main view model:
miSecondControl = new mySecondControl(param1, param2);
double myHeight = miSecondControl.height;
This secondary control does not use the MVVM patter but it has code behind, because I only want to use it to print a fixed document, so I think that in this case MVVM would make more complex the solution.
I need the heigh property of the control to know if I need to create a new page because I don't have space in the actual page.
Thanks.
Height/Width are values that are specified at design/layout time.
Use FrameworkElement.ActualHeight and FrameworkElement.ActualWidth to get the rendered Height/Width of a control.
I want to add large string content to a container dynamically.
There are 60 different contents(strings) to be displayed in this container.
To add the string to container, I am adding a TextArea(empty border with 100% transparency).
The problem is that TextArea offers scroll and I do not want it to scroll. Instead I want to grow(increase height) according to content. I am unable to achieve this.
Can you help me out with this?
Or can I use any other component for the purpose?
I am using LWUIT with J2ME.
You can derive text area and return false for isScrollableY() although it should generally work seamlessly even if you don't do that (since your parent layout is scrollable). Is it possible you changed the text area and don't revalidate the parent form on the EDT?
There are problems with text area layout when it is modified by a separate thread (race condition with the layout code).
First put the TextArea.setSingleLineTextArea(false) , and grow by content true.