How to call setNeedsDisplayInRect using performSelectorOnMainThread?
How to call setNeedsDisplayInRect using performSelectorOnMainThread? The problem is rect. I do not know how to pass the rect in performSelectorOnMainThread method. This method ask NSObject, but CGRect is not NSObject, it is just structure *.
//[self setNeedsDisplayInRect:rect];
[self performSelectorOnMainThread:@selector(setNeedsDisplay) withObject:0 waitUntilDone:YES];
}
-(void)drawRect:(CGRect)rect {
/// drawing...
}
I need to invoke setNeedsDisplayInRect method in MainThread from not Main Thread. Does anyone know how to do it?????????? Th开发者_StackOverflowanks in advance..
Really Thanks.
If you're on iOS 4.0 or later, you can use the following
dispatch_async(dispatch_get_main_queue(), ^{
[self setNeedsDisplayInRect:theRect];
});
On iOS 3.2 and earlier, you can set up an NSInvocation and run that on the main thread:
NSInvocation *invocation = [NSInvocation invocationWithMethodSignature:[self methodSignatureForSelector:@selector(setNeedsDisplayInRect:)]];
[invocation setTarget:self];
[invocation setSelector:@selector(setNeedsDisplayInRect:)];
// assuming theRect is my rect
[invocation setArgument:&theRect atIndex:2];
[invocation retainArguments]; // retains the target while it's waiting on the main thread
[invocation performSelectorOnMainThread:@selector(invoke) withObject:nil waitUntilDone:YES];
You may want to set waitUntilDone to NO unless you absolutely need to wait for this call to finish before proceeding.
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