edwardinubuntu/painter

The Painter app turns the iPhone screen into a virtual canvas. The user paints by dragging one or more fingers across the screen.

painter's Issues

The color and lineWidth can't pass to FlipsideView

Property color and property lineWidth can't pass to FlipsideView, and on the other side, after configure the color and lineWidth, can't pass back to MainView too.

Can't appends a straight line to UI

Even if the code has run into drawSquiggle method, but the UI still don't have the line. Which we expect appends a straight line segment from the current point to the provided point.

// draws the given squiggle into the given context
- (void)drawSquiggle:(Squiggle *)squiggle inContext:(CGContextRef)context {
  ...
  // move to the point
  CGContextMoveToPoint(context, firstPoint.x, firstPoint.y);
  ...   
  // draw a line from each point to the next in order
  for (int i=1; i < [points count]; i++) {
    NSValue *value = [points objectAtIndex:i];
    CGPoint point;  // declare a new point
    [value getValue:&point];    // store the value in point

    // draw a line to the new point
    CGContextAddLineToPoint(context, point.x, point.y);
  }  // end for
  ...
  CGContextStrokePath(context);
  ...
}

Can't clear the entire drawing from the screen.

The user can shake the iPhone or press erase button, still can't clear the entire drawing from the screen.

After calling the resetView, self setNeedsDisplay will calling into drawRect method, but int the drawRect function haven't implement the clear the drawing yet.

- (void)resetView {
    [squiggles removeAllObjects];
    [finishedSquiggles removeAllObjects];
    [self setNeedsDisplay]; // refresh the display
}

// An empty implementation adversely affects performance during animation.
- (void)drawRect:(CGRect)rect {
    // Drawing code.
    CGContextRef context = UIGraphicsGetCurrentContext();
    
    for (Squiggle *squiggle in finishedSquiggles)
        [self drawSquiggle:squiggle inContext:context];
    
    for (NSString *key in squiggles) {
        Squiggle *squiggle = [squiggles valueForKey:key];
        [self drawSquiggle:squiggle inContext:context];
    }
}