IOS：地图以MKUserTrackingModeFollowWithHeading开头

Question

在我的应用程序中，我想打开一个viewcontroller，里面有一张地图。在视图中加载我这样做：

- (void)viewDidLoad
{
    [super viewDidLoad];
    annotationPointArray = [[NSMutableArray alloc]init];
    [self organizeMap];
    modalMap = TRUE;

    [map setUserTrackingMode:MKUserTrackingModeFollowWithHeading animated:YES];

    [titleLabel setFont:[UIFont fontWithName:@"RemachineScriptPersonalUse" size:60]];
}

你可以看到我想用MKUserTrackingModeFollowWithHeading启动我的应用程序，但它不起作用，只有当我使用IBAction时它才能正常工作，这个：

- (IBAction)changeVisualMap:(id)sender{
    if (!modalMap){
        modalMap = !modalMap;
        [map setUserTrackingMode:MKUserTrackingModeFollowWithHeading animated:YES];
        [changeModalView_bt setImage:[UIImage imageNamed:@"map_bt_2.png"] forState:UIControlStateNormal];
        [changeModalView_bt setImage:[UIImage imageNamed:@"map_bt_2.png"] forState:UIControlStateHighlighted];
    }
    else{
        modalMap = !modalMap;
        map.userTrackingMode = MKUserTrackingModeFollow;
        [changeModalView_bt setImage:[UIImage imageNamed:@"map_bt_1.png"] forState:UIControlStateNormal];
        [changeModalView_bt setImage:[UIImage imageNamed:@"map_bt_1.png"] forState:UIControlStateHighlighted];
    }

}

为什么？

Answer 1

viewDidLoad可能为时尚早。请尝试在viewDidAppear中设置跟踪模式。