Java swing app, can't set app icon

[vestal bramble]

I have a java swing app and I want it so that when I run my program (from terminal) and it loads the app the icon will be different other than the default.

But my program keeps failing to find the correct path with bs like Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException: Cannot invoke "java.net.URL.toString()" because "url" is null even with absolute path & relative path that I think is correct (as I have printed the classpath out)

[plush pond]

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[frozen fern]

don't close it xD
can you also share your file structure

[vestal bramble]

Tryna figure out how best to

The class is <project-root>src/com/Schoolio/MainWindow

[frozen fern]

a screenshot works, In theory I just need the resource folder

[vestal bramble]

It's the hamster image I want rn

In mainwindow I call String ICON_PATH = "/com/Schoolio/views/hamster.jpeg"; final Toolkit defaultToolkit = Toolkit.getDefaultToolkit(); final URL imageResource = Main.class.getClassLoader().getResource(ICON_PATH); final Image image = defaultToolkit.getImage(imageResource);

[frozen fern]

is this intelliJ ?

[vestal bramble]

Yh

[frozen fern]

then you haven't configured your resource path properly, from the looks of it you are currently in the source folder

[vestal bramble]

I am

Images have to be in the resource folder?

[frozen fern]

Preferably yes

Do you use a build tool like maven or gradle ?

[vestal bramble]

Gradle yes

gradle run to start it

[frozen fern]

first of all create a new folder called resources or whatever, move your image in there.
Then show me your build.gradle file

[vestal bramble]

Ok

Gradle

[frozen fern]

you are still in the source folder

[vestal bramble]

yh

[frozen fern]

create a new folder outside the source folder

or move your existing one there.

[vestal bramble]

Ok done

resources folder at the root

[frozen fern]

now edit your sourceSets to the following:

sourceSets {
        main {
                java {
                        srcDirs= ['java']
                }
                resources {
                        srcDirs= ['resources']
                }
        }
}

[vestal bramble]

Kaptain Iglo is called Bird's Eye in the uk

Now what?

[frozen fern]

they better have the same mascot

[vestal bramble]

They do

Could not find or load main class com.Schoolio.Launcher

[frozen fern]

Your path should be /hamster.jpeg when loading form the class and hamster.jpeg when loading from the classloader

[vestal bramble]

Omg no way

At last

That's been a 7 hour task

[frozen fern]

i mean I could be kind of rude and just say something along the lines of read the documentation but we are going to pretend I didn't say that xD

[vestal bramble]

Which documentation Java swing?

Or gradle

Also it takes about 3 seconds to change from the default app icon to my hamster, which is a bit of a shame

[frozen fern]

gradle. For example this link is basically the answer you have been looking for: https://stackoverflow.com/questions/41315434/setting-the-resource-folder-in-a-java-gradle-project

[frozen fern]

you can load it at the very beginning.

That should speed things up

[vestal bramble]

Thx

It's often about knowing thte right questions to ask

[vestal bramble]

Load it where exactly?

[frozen fern]

that's true.

when configuring your JFrame basically

[vestal bramble]

Mm it is essentially the first thing I do on the jframe

Oh actually ik what it miht be

Haha

It was my authentication was running first

Taking like 2 seconds to get a response

[frozen fern]

your authentication is running on the EDT ?

[vestal bramble]

Eau de toilette

[frozen fern]

exactly no, EDT = Event Dispatch Thread the thread swing uses to send events and configure its components

[vestal bramble]

Nah my auth is just running in my class

I'm a PHP dev I'm not used to lots of this low level stuff

It's running in my mainwindow class which creates the JFrame

[frozen fern]

but you aren't calling your class with something like SwingUtilities.invokeLater()

[vestal bramble]

Indeed i am not

[frozen fern]

alright then nothing to worry about.

[vestal bramble]

Oh no i am actully

I am calling the MainWindow class whihc has the ui and the auth through that

[frozen fern]

yeah maybe don't do that.

At least leave the authentication outside of the swing thread.

[vestal bramble]

So leave the invokelater but make a new thread to do the auth

[frozen fern]

well you could just quickly try if the Jframe speeds up when you don't use invokeLater

[vestal bramble]

Yh it does

Which is gud

[frozen fern]

you don't really need invokeLater because setting the frame to visible should repaint everything anyways

[vestal bramble]

Idrk what it did anyway

But one last thing

Do I need to move the authentication stuff into a separate thread somehow, to speed up load times of new frames n stuff

And new JPanels

[frozen fern]

as long as you don't use invokeLater your main thread and the swing thread should run in parallel. So I would say you don't. If you have problems with panels not refreshing, call paint on the panel or the frame and that should hopefully fix that

[vestal bramble]

Do I need to explicitly declare a main and swingg thread or java does it for me?

[frozen fern]

java does that for you. Btw don't use show its deprecated. Use setVisible(true) instead.

[vestal bramble]

Yh show actually just calls setVisible

Thanks Fish Finger, have a nice rest of ur day

[plush pond]

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