如何实现loadView？

Question

我创建了一个名为 GraphView 的自定义视图。加载视图时我得到的只是一个空白的黑屏。这是我的代码：

在 GraphViewController.m 中：

@synthesize graphView, graphModel;

- (void)loadView
{   
    GraphView *aGraphView = [[GraphView alloc] initWithFrame:CGRectZero];
    self.view = aGraphView;
    self.graphView = aGraphView;

    [aGraphView release];
}

我不确定为什么当我尝试在 GraphViewController.m 中实现 loadView 时出现黑屏

Answer 1

您没有为 GraphView 对象设置框架：

GraphView *aGraphView = [[GraphView alloc] init];

UIView 的指定初始值设定项是-initWithFrame:。执行如下操作（根据需要设置视图的大小/原点）：

GraphView *aGraphView = [[GraphView alloc] initWithFrame:CGRectMake(0, 0, 100, 100)];

Answer 2

我需要在 loadView 中将背景色设置为白色

- (void)loadView
{   
    GraphView *aGraphView = [[GraphView alloc] initWithFrame:CGRectZero];
    aGraphView.backgroundColor = [UIColor whiteColor];
    self.view = aGraphView;
    self.graphView = aGraphView;

    [aGraphView release];
}