Graver

美团开源Graver框架：用“雕刻”诠释iOS端UI界面的高效渲染

一、attributedItem

- (void)basicUseDemo
{
    //WMMutableAttributedItem : 视图绘制单元(自己拼接的！)
    WMMutableAttributedItem *text1 = [WMMutableAttributedItem itemWithText:@"Graver是一种高效的UI渲染框架。"];
    [text1 setFont:[UIFont systemFontOfSize:18]];
    [text1 setColor:WMGHEXCOLOR(0xff8205)];
    
    //绘制 Item
    WMGMixedView *view = [[WMGMixedView alloc] initWithFrame:CGRectZero];
    view.attributedItem = text1;
    
    CGSize size = [text1.resultString wmg_sizeConstrainedToWidth:self.view.frame.size.width - 20];
    view.frame = CGRectMake(10, 10, size.width, size.height);
    [_scrollView addSubview:view];
}

点击attributedItem

- (void)setAttributedItem:(WMMutableAttributedItem *)attributedItem
{
    if (_attributedItem != attributedItem)
    {
        _attributedItem = attributedItem;
        
        //异步的操作！！！
        [self setNeedsDisplayAsync];
        
        _pendingAttachmentUpdates = YES;
    }
}

点击setNeedsDisplayAsync->WMGAsyncDrawView.m

- (void)setNeedsDisplayAsync
{
    self.contentsChangedAfterLastAsyncDrawing = YES;
    //需要更新
    [self setNeedsDisplay];
}

点击setNeedsDisplay

- (void)setNeedsDisplay
{
    [self.layer setNeedsDisplay];
}

点击setNeedsDisplay->WMGAsyncDrawLayer.m

- (void)setNeedsDisplay
{
    [self increaseDrawingCount];
    [super setNeedsDisplay];
}

[super setNeedsDisplay]; CALayer调用setNeedsDisplay

二、graver接管异步绘制