I've got a problem, that swing components in different parts of program have sometimes wrong background. For example this or this.
As I mentioned, the bug is not permanent and it can appear in one place one time and never after. But still there are some places, where I can randomly reproduce it. Unfortunately, I don't see any solutions.
Has anyone some ideas how can I fix it?
If you set your components to non-opaque (I think the call is setOpaque(false)), that will let the background colour of the component that it is on top of show through.
in addition to what Paul said, there's the question if you use self made components.
Such components should take care of their complete occupied region (or at least the invalidated regions) in the paint callback. An error seen quite often that leads to strange artifacts when moving or resizing is that only "important" parts are repainted, for example a string to be shown, without drawing the background.
In this case, anything previously blitted ther will show through.
Related
I was wondering if there was a way to make one component (in this case a JPanel) visible in more than one of the tabs.
I have a simple JFrame which is completely filled with a JTabbedPane. Each tab has a slightly different function, which is why they're in different tabs. However, they each output the same type of information. I was wondering if there was a way to make it so the same output panel could be seen in all the tabs, without having to create one panel for each tab.
I realize that it is impossible to add one component multiple times (and have it display independently each time), which is why I'm not optimistic about this being possible, however if it is, it would make my code much cleaner. In the case that this is not possible, I am completely open to alternate suggestions that achieve a similar result. I am in the very beginning of my project, so it won't be too difficult to change things.
This image gives a rough idea of what I'm trying to make it look like:
I have searched around for anyone dealing with this issue, however I have had little luck finding anything relevant. If I missed something, I apologize for wasting your time.
Simple as the title says. They just won't appear. I don't know why. BTW, The table is added on a panel that has setLayout(null); So, I don't know if that affects it. I just really don't know where the problem is coming from. I'm completely clueless.
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Change DisplayTab.add(table); to DisplayTab.add(scrollPane); and make use of appropriate layouts
Avoid using null layouts, pixel perfect layouts are an illusion within modern ui design. There are too many factors which affect the individual size of components, none of which you can control. Swing was designed to work with layout managers at the core, discarding these will lead to no end of issues and problems that you will spend more and more time trying to rectify
I have a number of various components in a very large JavaEE application. As such, debugging is a pain, and sadly I cannot provide an SSCCE that accurately depicts the problem I'm having.
In a nutshell, somehow my fonts change by themselves for things like JLabels and JTabbedPanes. Without ever touching them, they're being repainted as bold, italicized, dramatically changed in size, or any combination thereof.
Simple question: why?
If I step through the Eclipse debugger, no changes are made, ever. So time is somehow a factor.
I'm still a Java grasshopper (working by myself), and haven't built this program in such a way that the EDT is a sacred object. I'm worried that because I'm potentially not making all repaint() calls on the EDT that the JTabbedPane, JLabel and other font properties are being reset and repainted.
EDIT:
Forgot to say that I'm constrained to Java 1.5.
I think I've narrowed it down to an issue with using HTML in JLabels and JTabbedPane tab titles...but past that I've got no idea. With regards to the JTabbedPane, it's going into the drawing methods with the right Font/FontMetrics objects, but for whatever reason it will very rarely (sometimes more often; still haven't figured out the timing trigger) switch up what font, style, and even size at which it's painting the text.
I am working with an application that is experiencing painting issues on some users computers when the mouse passes over the tabs in a JTabbedPane. They also occasionally have similar issues on other interactive components like JButtons. I have only ever seen this error occur on mouse overs.
The application is being run with 1.6.0_20 and I have already tried the flag recommended in update 10 in case it was an issue with D3D (-Dsun.java2d.d3d=false).
Since I am a new user I cannot post a picture to illustrate this error. The best example I can think of is using Windows paint eraser on an image would create something similar to what I am seeing.
I appreciate any help you can provide.
Without an sscce that exhibits the problem you describe, it's hard to be specific, but this reminds me of the rendering artifact associated with setting the opaque property to true without completely rendering the area defined by a component's bounds. In particular, if you override paintComponent() and "do not honor the opaque property, you will likely see visual artifacts." Finally, the default opacity setting of some components varies by Look & Feel, so the effect may be platform dependent.
Similar question, but not exactly the same.
table.showColumn() is helpful, but the scrolling only has the granularity of the column width. But I want a more precise control of the scroll location.
Consider the following use case. I have two tables that I know are of the same width and have the same column widths. And I want to implement some kind of a scroll synchronizer so that when the user scrolls one table (horizontally), the other table scrolls to the same location.
EDIT:
On the Eclipse forum there seems to be the same question and some working ideas, but no resolution.
EDIT:
I discovered this behavior on Windows
The method setOrigin(x,y) in ScrolledComposite should help:
Scrolls the content so that the specified point in the content is in the top left corner. If no content has been set, nothing will occur. Negative values will be ignored. Values greater than the maximum scroll distance will result in scrolling to the end of the scrollbar.
I'm afraid I can't get a satisfying result in Windows Vista/7 either, but felt I was getting close.
I believe you will have to grab the Table's horizontal scroll bar by using table.getHorizontalBar(). Then, you can specify scrollbar.setSelection() to make it move to a specified position.
This is where I get stuck. Somehow, you have to notify either the Table or the ScrollBar that the value has changed. I've tried everything from update() to notifyListener(), but no dice. It seems that it is merely a matter of laying out, but layout() doesn't have any effect, either.
Incidentally, bear in mind that the ScrollBar's parent (type Scrollable) is not a ScrolledComposite like I had expected, but is actually the Table itself.
I hope this gives you some ideas and helps you find a solution. If so, please let me know, since it's bugging me now, too!
Having poked around in the ScrollBar source a bit, it looks like there are numerous (windows) bugs that have been overcome at one point or another. This may be another, though you didn't mention your OS, nor did Paul, so it's hard to tell.
All the "change the scroll bar position" functions end up calling SetScrollInfo which is package private. I suspect that the intention is for this to actually update things the way you want.
None of that solves your problem. Thankfully the same source also hints at a solution:
Slider.
You'd have to reimplement all the scrollbar behavior within slider, but once done, that should give you the control (har) you want. Hopefully. OTOH, you may run into exactly the same OS bug (if bug it be), and be back at square one.
At THAT point, you definitely register it as an Eclipse UI bug.
PS: Have you searched the Eclipse Bugzilla for anything similar? Poking around a bit turned up this bug related to the scroll bar being out of sync with a tree view in the Navigator (on PC Linux-Motif, but working fine in Windows). I suspect you'll find similar issues if you dig a bit more.