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Ghoser777 · Sep 8, 2001, 08:46 PM

Yeah, so this question isn't a dumbass one, I swear. Here's what I want to do: draw an image in an NSView that the user picks and can choose at a later time. I have written the code in both Java and ObjC so I'm not discriminating against anyone here. Here it is:

Java
<BLOCKQUOTE>code:<HR><pre>
/* ImageTester */

import com.apple.cocoa.foundation.*;
import com.apple.cocoa.application.*;

public class ImageTester extends NSView
{

//NSTimer recompositeTimer;
NSColor color;

public ImageTester(NSRect frame)
{
super(frame);
}

public void awakeFromNib()
{
//recompositeTimer = new NSTimer(1, this, new NSSelector("updateView", new Class[]{this.getClass()}), this, true);
//NSRunLoop.currentRunLoop().addTimerForMode(recompo siteTimer, NSRunLoop.DefaultRunLoopMode);
}

public void drawRect(NSRect frame)
{
NSColor.clearColor().set();
NSBezierPath.fillRect(this.bounds());

if(color!=null)
{
color.set();
NSBezierPath.fillRect(this.bounds());
}
}

public void setImage(NSButton sender)
{
NSOpenPanel me = NSOpenPanel.openPanel();
if(me.runModalForTypes(NSImage.imageFileTypes() )==NSPanel.OKButton)
color = NSColor.colorWithPatternImage(new NSImage(new NSData(new java.io.File((String)me.filenames().objectAtIndex( 0)))));
setNeedsDisplay(true);
}

public void updateView(NSTimer a)
{
setNeedsDisplay(true);
}

}
[/code]

ObjC
<BLOCKQUOTE>code:<HR><pre>
/*ImageTester.h */
#import <Cocoa/Cocoa.h>

@interface ImageTester : NSView
{
NSColor *color;
}

- (id)initWithFrame

NSRect)frame;
- (void)dealloc;

- (void)drawRect

NSRect)rect;

- (IBAction)setImage

id)sender;
@end

/*ImageTester.m */
#import "ImageTester.h"

@implementation ImageTester

- (id)initWithFrame

NSRect)frame
{
[super initWithFrame:frame];
return self;
}

- (void)dealloc
{
[color release];
[super dealloc];
}

- (void)drawRect

NSRect)rect
{
[[NSColor clearColor] set];
NSRectFill([self bounds]);
if(color!=nil)
{
[color set];
NSRectFill([self bounds]);
}
}

- (IBAction)setImage

id)sender
{
NSOpenPanel *me = [NSOpenPanel openPanel];
if([me runModalForTypes:[NSImage imageFileTypes]]==1)
{
[color autorelease];
color = [[NSColor colorWithPatternImage:[[NSImage alloc] initWithData:[NSData dataWithContentsOfFile:[[me filenames] objectAtIndex:0]]]] retain];
[self setNeedsDisplay:YES];
}
}
@end
[/code]

Of course they're linked in IB. But that has nothing to do with my problem. Everytime I set a new image, the ram usage goes up, even if I pick a significantly smaller image than the previous. I've been able to run up my ram usage to upwards of 100MB, which is really really bad.

My theory is that this has something to do with the way Cocoa caches images, but I don't know how to flush the cache. Does anyone know why my program likes to eat ram?

Hoping this isn't a dumbass question,
F-bacher

Apocalypse · Sep 9, 2001, 12:54 AM

I don't think that I can help you directly here but I do have a few concerns looking at the code (I am an Obj-C guy so that is what I will refer to).
I think that this init method:
<BLOCKQUOTE>code:<HR><pre>
- (id)initWithFrame

NSRect)frame
{
[super initWithFrame:frame];
return self;
}
[/code]
Should look something more like this:
<BLOCKQUOTE>code:<HR><pre>
- (id)initWithFrame

NSRect)frame
{
return [super initWithFrame:frame]; //remember that initWithFrame returns an id
}
[/code]

Although I would not be surprised if that were just a careless error when you posted the code here.

Another issue I am curious about is that the "color" object is sent the "autorelease" message right before you declare it and then send it the "retain" message. If you are handling the retain and release commands yourself I don't think that you should put in an autorelease. I think that this could cause some unusual behavior.
I would suggest replacing the autorelease message with an explicit release (don't forget to ensure that the variable is not NULL). Basically, I think that it comes down to a misinterpretation of what "autorelease" actually does.

That should solve the leak (before things weren't ever being deallocated). Also, I don't think that you need to implement "initWithFrame" at all since you don't do anything other than what the parent object does.

Hope that helps,
Jeff.

Ghoser777 · Sep 9, 2001, 02:36 AM

That's really funny, considering I coded it almost exactly the same way that Apple's example dot view app does

I'll give it a try,
F-bacher

Ghoser777 · Sep 9, 2001, 02:44 AM

Originally posted by Apocalypse:
Another issue I am curious about is that the "color" object is sent the "autorelease" message right before you declare it and then send it the "retain" message. If you are handling the retain and release commands yourself I don't think that you should put in an autorelease. I think that this could cause some unusual behavior.
I would suggest replacing the autorelease message with an explicit release (don't forget to ensure that the variable is not NULL). Basically, I think that it comes down to a misinterpretation of what "autorelease" actually does.

Okay, so know instead of sending autorelease to color, I send release. That has zero effect on the amount of ram that is used. And if it was as simple as that, I don't think my java version would be having the same probs.

And i just tried releasing my color object right after I fill the rect (because I always define my color object right before i draw my rect). Still no dice.

Back to the drawing board,
F-bacher

Wixar · Sep 9, 2001, 02:50 AM

Change

color = [[NSColor colorWithPatternImage:[[NSImage alloc] initWithData:[NSData dataWithContentsOfFile:[[me filenames] objectAtIndex:0]]]] retain];

To

color = [[NSColor colorWithPatternImage:[[[NSImage alloc] initWithData:[NSData dataWithContentsOfFile:[[me filenames] objectAtIndex:0]]] autorelease] retain];

unregistered · Sep 9, 2001, 03:09 AM

Originally posted by Apocalypse:

Although I would not be surprised if that were just a careless error when you posted the code here.

Another issue I am curious about is that the "color" object is sent the "autorelease" message right before you declare it and then send it the "retain" message. If you are handling the retain and release commands yourself I don't think that you should put in an autorelease. I think that this could cause some unusual behavior.
I would suggest replacing the autorelease message with an explicit release (don't forget to ensure that the variable is not NULL). Basically, I think that it comes down to a misinterpretation of what "autorelease" actually does.

The autorelease is actually fine where it is. The difference between autorelease and release is just timing. In the end, they both add up to 1 release being sent. There are times to use one over the other, but the difference won't cause a leak.

The return self; is also ok. Either way, it is the same pointer. It is just a matter of style.

You don't need to check if the object is NULL (or nil) because it is valid to send a message to a nil object.

Ghoser777 · Sep 9, 2001, 03:12 AM

Wixar, ur a genious! (although now I sound like an idiot on MaxOSX-dev, but what else is new?) So that fixes the Obj-C prob, but what's going on with Java, which is suppose to be good at garbage collection? I can't exactly send java object autorelease and retain messages.

Thanks,
F-bacher

unregistered · Sep 9, 2001, 03:12 AM

Originally posted by Wixar:
Change

color = [[NSColor colorWithPatternImage:[[NSImage alloc] initWithData:[NSData dataWithContentsOfFile:[[me filenames] objectAtIndex:0]]]] retain];

To

color = [[NSColor colorWithPatternImage:[[[NSImage alloc] initWithData:[NSData dataWithContentsOfFile:[[me filenames] objectAtIndex:0]]] autorelease] retain];

Just to elaborate on Wixar's correct solution... It is the NSImage that is leaking, not the NSColor.

Ghoser777 · Sep 9, 2001, 03:16 AM

Originally posted by unregistered:


Just to elaborate on Wixar's correct solution... It is the NSImage that is leaking, not the NSColor.

This makes a lot of sense to me now. Cool... but got any clue about what's going on with my java version?

F-bacher

Angus_D · Sep 9, 2001, 04:49 AM

Originally posted by Ghoser777:
This makes a lot of sense to me now. Cool... but got any clue about what's going on with my java version?

AFAIK, the java bridge just retains/releases the objects internally during garbage collection. If the object you have already has a retain count of 1 (or more) when it is handed across the bridge, it will never have its retain count reduced back down to 0. Can you call -release on objects that inherit from NSObject in Java? If not, you could use a really hackish workaround of creating some objc code that releases the object and then calling that across the bridge

Ghoser777 · Sep 9, 2001, 11:24 AM

No, I can't just send objects "go to hell" messages like you can in Obj-C. But I can make an Obj-C clss wrapper which I pass int the fileName of the image and will do the rest as posted above, returning the color object.
http://developer.apple.com/techpubs/...aBridge.2.html

This problem shouldn't exist though.
F-bacher

Angus_D · Sep 9, 2001, 01:58 PM

Originally posted by Ghoser777:
This problem shouldn't exist though.

Exactly, it's a bug. Submit a bug report http://developer.apple.com/bugreporter

Ghoser777 · Sep 9, 2001, 03:46 PM

Oh, this keeps getting better and better. You know that documented java wrapper thing? It's GONE! Caput. Removed. On OS X server you use to be able to make them, but with project builders made for OS X PB and beyond, the functionality has been removed.

If I can't figure out something soon, Steve's balls are mine!
F-bacher

3.1416 · Sep 9, 2001, 08:24 PM

You can make a Java Wrapper project using ProjectBuilderWO. At WWDC the Cocoa guys said that this capability would be added to the new Project Builder, they just haven't gotten around to it yet.

Ghoser777 · Sep 9, 2001, 10:36 PM

Well, i deleted ProjectBuilderWO because the new Project Builder was suppose to integrate WO support. Does anyone have a copy they could compress for me and load on a server? Or just a sample Java Wrapper project would probably do.

Thanks,
F-bacher