Quick question: clear jlabel contents holding icon

Hi All,
I've been searching through the JLabel documentation and I've been trying to remove a JLabel's contents that displays an image.
// Here is the add code
JLabel1.setIcon(myImage);
How would I remove/clear this icon? I've tried JLabel1.removeAll(), JLabel1.remove(), and even tried JLabel1.getComponentCount() but the component count returned as 0.
There's gotta be an easy one liner for this. Please help. Thanks!

Here's what the API documentation for JLabel has to say about setIcon:
setIcon
public void setIcon(Icon icon)
Defines the icon this component will display. If the value of icon is null, nothing is displayed.
The default value of this property is null.
So the easy one-liner isJLabel1.setIcon(null);

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Pixel VS DPI - Need to have a quick question cleared up!

Hello Adobe Forums!
I would consider myself an experienced designer, but I have a question that might seem rather mundane. To be completely honest, I just think I have overthought/overanalyzed it to a point where I confused myself!
In Photoshop, I have a 300 DPI psd image, that image size is 2"x1" and is 600x300px.
Now, my question is: is there a way to reduce the DPI in an effort to increase the pixels?
My goal is to have a larger amount of pixels at 72dpi for a web image. The theory makes sense in my head, but when put into practice, my image loses its quality. I need it to be sharp.
Aside from all of this, if I do have to end up resampling, are there other programs that resample more effectively than Photoshop?
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Exactly. Web images have no PPI, only the pixel dimensions. Your image is 600px x 300px; ignore the 300 PPI, ignore the 2" x 1". Focus only on the 600px x 300px. When you use this image in a web layout, it will take up exactly 600px x 300px. Whether or not that size works for what you're trying to do is up to you, it is what it is. But the image is not 72 PPI or 300 PPI or any other PPI, since you're not printing it.
In fact, even images destined for print don't have a specific PPI until you set the size at which they will be printed. Photoshop provides the PPI of the image based on a particular output size for convenience, but the only true measure of the resolution of a digital image are the pixel dimensions, period.
Here's a short article I wrote for our customers w/ digital cameras, to explain digital resolution and print resolution:
WHAT IS RESOLUTION?
The resolution of a digital image is the number of pixels it contains, plain and simple. If you open an image into Photoshop and go to Image > Image Size, the top section of the dialog box shows you the total number of pixels in your image. This is the actual resolution of the image, independent of the size you plan to use it.
For example, a photo taken with a Canon Digital Rebel XSi might have a resolution of 4272 x 2848. This means there are 4272 pixels across, and 2848 pixels down, that make up the image.
Most digital cameras are rated as a certain number of "megapixels." A megapixel is one million pixels, and camera manufactures calculate the megapixels by multiplying the maximum width by the maximum height that their camera can capture. In the example above, the Digital Rebel XSi is a 12 megapixel camera (4272 times 2848 = 12,166,656 pixels).
HOW BIG IS A PIXEL?
A pixel has no size of its own, it is simply the smallest single "unit" in a digital image. In fact, the word pixel derives from the term "picture element." If you zoom in close enough in Photoshop you can see all the individual pixels that make up an image. (In Photoshop CS4 there is also a pixel grid that you can enable to make it easier to see.)
SO WHAT ABOUT PPI?
You've probably heard a lot about pixels per inch (PPI) or dots per inch (DPI), but what does that actually mean?
Pixels per inch is a relative measurement of resolution, that takes into account the size you're going to print the image. Now there's a mouthful! Don't let that confuse you, though, it's actually really simple to calculate: take the total number of pixels and divide by the size you plan to use it.
So for example, if you take that 4272 x 2848 image I mentioned earlier and print it 10 inches wide, the resolution would be 427.2 PPI (4272 divided by 10).
For optimum print quality, we look for 300 PPI at print size, and a similar calculation will tell you how big you can print your images. Using that same image, take 4272 and divide by 300. The result is 14.24, so you can print that image as large as 14.24" without the image looking low-res or pixellated, or without doing any resampling in Photoshop.
Oh, and the proper unit of measurement for the resolution of a digital image at a particular print size is PPI. The proper unit of measurement of the resolution of an output device is DPI. The two are not synonymous nor interchangeable -- images never contain dots, only pixels, and printers never print with pixels, only dots.
OK, SO YOU'RE SAYING RESOLUTION AND PPI ARE NOT THE SAME THING?
Right. They're related, but not the same. The easy way to think about this is that PPI is the "print resolution" of the image.
Let's look at another example: say you have an image that is 1500 pixels x 1500 pixels, and you print it at 5" wide. 1500 divided by 5 is 300 PPI. If you print the same image at 10" wide, 1500 divided by 10 is 150 PPI. The print resolution has changed because you're using the image at a much larger size, but the actual resolution of the image (1500 x 1500) has not changed.
CAN'T I JUST INCREASE THE RESOLUTION IN PHOTOSHOP?
You can, but it's not the same as if the image had the correct resolution to start with.
If you ask Photoshop to increase the resolution of an image, it needs to calculate how to add all those new pixels you're asking for. It uses some pretty complex algorithms to do this, but it's still "inventing" pixels that were never there. There is a limit to how much you can artificially increase the resolution of an image without it being visible (either as blurriness or jaggedness). And don't forget: a low-resolution original doesn't contain as much detail as a high-res image. Photoshop can only interpolate from the data that exists in the file, so it won't magically add in all that missing detail.
A good rule of thumb is if your image would be less than 225 PPI or so at the size you want to use it, you would be better off retaking the photo than upsampling in Photoshop. Anything less than that and it will almost certainly appear low-res when printed, and you would see artifacts if you upsample it.

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Jason

Heya,
1. If you're asking if you have something like the "roving" keyframes in AE...well, kinda. Keyframes on footage, shapes, generators, particles, replicators—objects that create an image—don't seem to scale. But keyframes on secondary objects like behaviors and filters do scale.
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Hi -
Just a quick question about Oracle 10gR2 Dataguard. I'm in the process of creating dataguard standby, which is running for few hours and could take few more hours because of the size and the standby's network latency, and i'm using OMS to create the DG. I'm in a situation now to create new tablespace(A) and also one more datafile to the existing tablespace(B).
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I am wondering How to fix the " flashing question mark after the finder icon when starting up" without an apple keyboard. I have 2 of those .7Ghz emacs so just wanna fix them
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Hi,
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https://wiki.ubuntu.com/PowerPCFAQ
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Say I have an array A = [1,2,3,4,5]
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But can somebody explain to me why you can't just go B = A?
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Kayaman wrote:
JT26 wrote:
Array A=[1,2,3,4,5] ----> Here A is a reference variable which points to memory locations A[0],A[1],A[2],A[3],A[4] which could not be continueous.Actually no. What you have there is a syntax error. And please don't confuse people by talking about non continuous memory locations. That's simply wrong.And 100% irrelevant for the question at hand.
>
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Is OS X installed?
Try a Startup Manager boot. Hold Option while starting.
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Reset the PRAM.
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Hi,
I created the most awesome LabVIEW report ever at my desk using a trial version of the RGT and Office 2003. I took this to my production machine and ")@#(&%(*#^%()^!!!" The production machine has office 2007 and a fully licensed version of the RGT. Both machines have LabVIEW 8.6.0. I've read all the stuff about these errors and something about classes and dll's and whatnot's. So my quick question, is: Instead of matching the versions of Microsoft Office as recommended, can I just rewrite from scratch the VI that creates this world's most awesome LabVIEW report on the production machine to create the same effect?
Solved!
Go to Solution.

Hi
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Hi there,
I just moved from Windows to Mac, meaning I had to move my iTunes library from the old PC to my new MBA.
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The .xml is lacking some information such as ratings, date added, and play count. Using the .itl includes this information but cannot be imported using the method you did.
A complete library is everything in the iTunes folder. By using the method you did you left the artwork behind in the artwork folder on the other machine.
Selecting the media folder in preferences does not get iTunes to recognize the media. All it does is tell iTunes to start storing new media in that location.
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What are all those iTunes files? - http://www.macworld.com/article/139974/2009/04/itunes_files.html
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Quick question: clear jlabel contents holding icon

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