macOS custom view don't work after 3days trying

[ginjko]

I got a custom view displaying a picture and a path with a draw rect method, it loads fine and the drawing code works. But I need to update this view with a parameter that i get computed from an other class . I get this parameter update fine with a void method and at the of this method i got a setneeds display. but it does not work. If i put a self draw rect method it works but it draws my view on the bottom left corner.
I spent hours trying to solve this I just can t do it.

I attach my code to this post

Can someone help me ....

 

[Sydde]

The origin of a view ( 0, 0 ) is the lower left corner by default. You can either learn how to flip a view and how to draw images in a flipped view (NSImage also needs to be flipped to draw right) or you can learn to deal with working from the bottom up.

 

[kwfl]

as sydde said, you may need to filp your view.

Try adding to your view class implementation

-(BOOL)isFlipped
{
	return YES;
}

And for the setNeedsDisplay method. Just double check you are calling it on view class and not another class!

 

[ginjko]

so to update the content of my view i should redraw it up side down and flip it again

 

[Sydde]

so to update the content of my view i should redraw it up side down and flip it again

You need do only two things: tell the images that they will be drawing in a flipped view (look up the docs for NSImage, there is a method for this), and do your drawing with a top-down coördinate system in mind. I am pretty sure everything else takes care of itself.

 

[ginjko]

My problem is that i call this void from an other class, and this is supposed to update K_imput, witch is the crucial value in my drawing.
If I update it through an IBaction and then call the set needs display it works but this value needs to be computed first by my other class and I can't enter it via an IBaction.

here is the void supposed to update this value.


- (void) set_k:(double)k_update;
{
k_imput = k_update;

printf(" K imput %f\n", k_imput);

}

I can read the value updating in the debuger console and it works fine,
but i have an other printf to read this same value inside the drawrect void.
And inside the draw rect void, this value stays nul.

Why !!!!!

 

[jiminaus]

Just a wild theory, but does your other class have a reference to same instance of your view?

If you put the following code at the start of each of your methods of moon_display_view:

NSLog(@"%s: %@", __PRETTY_FUNCTION__, self);

it will log the method name and a description of your moon_display_view into the debugger console. The description will include it's "address". Is the "address" always the same?