UITableView 背景只填了一半？答案

【问题标题】：UITableView background filled only half?UITableView 背景只填了一半？
【发布时间】：2011-12-28 15:41:40
【问题描述】：

不幸的是，我用背景视图（渐变）填充了我的tableView，但只填充了一半的背景。

你知道如何填补下半场吗？

提前致谢！

代码：

UIView* myView = [[GradientBackground alloc] initWithFrame:CGRectMake(self.view.bounds.origin.x, self.view.bounds.origin.y, self.view.bounds.size.width,  self.view.bounds.size.height)];

myTableView.backgroundColor = [UIColor clearColor];

myTableView.backgroundView = myView;

和渐变背景.m

- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
    // Initialization code
}
return self;
}

- (void)drawRect:(CGRect)rect 
{
CGContextRef currentContext = UIGraphicsGetCurrentContext();       
CGGradientRef glossGradient;
CGColorSpaceRef rgbColorspace;
size_t num_locations = 2;
CGFloat locations[2] = { 0.0, 1.0 };
CGFloat components[8] = {  25.0 / 255.0, 89.0 / 255.0, 140.0 / 255.0, 0.65,  // Start color
25.0 / 255.0, 89.0 / 255.0, 140.0 / 255.0, 1.0 }; // End color


//( 25.0 / 255.0 ) green:( 89.0 / 255.0 ) blue:( 140.0 / 255.0 )

rgbColorspace = CGColorSpaceCreateDeviceRGB();
glossGradient = CGGradientCreateWithColorComponents(rgbColorspace, components, locations, num_locations);

CGRect currentBounds = self.bounds;
CGPoint topCenter = CGPointMake(CGRectGetMidX(currentBounds), 0.0f);
CGPoint midCenter = CGPointMake(CGRectGetMidX(currentBounds), CGRectGetMidY(currentBounds));
CGContextDrawLinearGradient(currentContext, glossGradient, topCenter, midCenter, 0);

CGGradientRelease(glossGradient);
CGColorSpaceRelease(rgbColorspace); 
} 

25.0 / 255.0, 89.0 / 255.0, 140.0 / 255.0, 1.0 }; // End color


//( 25.0 / 255.0 ) green:( 89.0 / 255.0 ) blue:( 140.0 / 255.0 )

rgbColorspace = CGColorSpaceCreateDeviceRGB();
glossGradient = CGGradientCreateWithColorComponents(rgbColorspace, components, locations, num_locations);

CGRect currentBounds = self.bounds;
CGPoint topCenter = CGPointMake(CGRectGetMidX(currentBounds), 0.0f);
CGPoint midCenter = CGPointMake(CGRectGetMidX(currentBounds), CGRectGetMidY(currentBounds));
CGContextDrawLinearGradient(currentContext, glossGradient, topCenter, midCenter, 0);

CGGradientRelease(glossGradient);
CGColorSpaceRelease(rgbColorspace);

【问题讨论】：

标签： objective-c ios ipad uitableview background

【解决方案1】：

您是否在 myView 上设置了 autoresizemask？尝试将其设置为可变高度和宽度。

您还将 myView 的框架设置为 self.bounds 而不是 myTableView.bounds。

【讨论】：

试过这个UIView* myView = [[GradientBackground alloc] initWithFrame:CGRectMake(myTableView.bounds.origin.x, myTableView.bounds.origin.y, myTableView.bounds.size.width, myTableView.bounds.size.height)]; myView.autoresizingMask = UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleWidth; 但我没有运气。

【解决方案2】：

知道了。我的渐变代码是错误的。我使用了视图的中间，但渐变应该在底部结束。

rgbColorspace = CGColorSpaceCreateDeviceRGB();
glossGradient = CGGradientCreateWithColorComponents(rgbColorspace, components, locations, num_locations);

CGRect currentBounds = self.bounds;
CGPoint topCenter = CGPointMake(CGRectGetMidX(currentBounds), CGRectGetMaxY(currentBounds));
CGPoint bottomCent = CGPointMake(CGRectGetMidX(currentBounds), CGRectGetMinY(currentBounds));
CGContextDrawLinearGradient(currentContext, glossGradient, topCenter, bottomCent, 0);

CGGradientRelease(glossGradient);
CGColorSpaceRelease(rgbColorspace);

【讨论】：