當mapview打開時，動畫縮放到位置/地圖地標iOS

Question

我在其他應用程序中看到了它exmaple ios 6 starbucks，當我的mapview打開時，我希望它顯示整個英國/英國島嶼的區域，然後我希望它放大到我指定的位置區域點。

更新的代碼：

- (void)viewDidLoad 
{ 

[super viewDidLoad]; 
// Do any additional setup after loading the view. 
[mapView setMapType:MKMapTypeStandard]; 
[mapView setZoomEnabled:YES]; 
[mapView setScrollEnabled:YES]; 
MKCoordinateRegion region = { {0.0, 0.0 }, { 0.0, 0.0 } }; 
region.center.latitude = 54.5; 
region.center.longitude = -3.5; 
region.span.longitudeDelta = 10.0f; 
region.span.latitudeDelta = 10.0f; 
[mapView setRegion:region animated:NO]; 

[self performSelector:@selector(zoomInToMyLocation) 
      withObject:nil 
      afterDelay:2]; //will zoom in after 1.5 seconds 
} 

-(void)zoomInToMyLocation 
{ 
MKCoordinateRegion region = { {0.0, 0.0 }, { 0.0, 0.0 } }; 
region.center.latitude = 51.502729 ; 
region.center.longitude = -0.071948; 
region.span.longitudeDelta = 0.19f; 
region.span.latitudeDelta = 0.19f; 
[mapView setRegion:region animated:YES]; 

[mapView setDelegate:self]; 

[self performSelector:@selector(selectAnnotation) 
      withObject:nil 
      afterDelay:0.5]; //will zoom in after 0.5 seconds 

} 

-(void)selectAnnotation 
{ 

DisplayMap *ann = [[DisplayMap alloc] init]; 
ann.title = @"Design Museum"; 
ann.subtitle = @"Camberwell, London"; 
ann.coordinate = region.center; 
[mapView addAnnotation:ann]; 

} 

不知道它是正確的，因爲如果你想開始顯示一個區域，然後放大的誤差是此行

ann.coordinate = region.center; 

Answer 1

，你必須發出兩個或更多setRegion來電，因爲setRegion本身不允許您控制起始區域或動畫的速度。

在viewDidLoad，設定初始區域的span所以整個英國是可見的（嘗試10.0代替0.15增量）。您還可以爲初始區域設置animated至NO。

隨後的viewDidLoad結束前，安排放大到在幾秒鐘後執行：

- (void)viewDidLoad 
{ 
    ... 

    [self performSelector:@selector(zoomInToMyLocation) 
       withObject:nil 
       afterDelay:5]; //will zoom in after 5 seconds 
} 

的zoomInToMyLocation方法可能是這樣的：

-(void)zoomInToMyLocation 
{ 
    MKCoordinateRegion region = { {0.0, 0.0 }, { 0.0, 0.0 } }; 
    region.center.latitude = 51.502729 ; 
    region.center.longitude = -0.071948; 
    region.span.longitudeDelta = 0.15f; 
    region.span.latitudeDelta = 0.15f; 
    [mapView setRegion:region animated:YES]; 
} 

一件事在使用performSelector時，您可能必須注意在呼叫計劃運行之前，如果視圖已關閉或解除分配，則取消掛起的呼叫。例如，如果用戶在加載後兩秒鐘關閉視圖。三秒鐘後，預定的方法仍可能會被調用，但會在視圖消失後崩潰。爲了避免這種情況，取消viewWillDisappear:任何未決的執行或酌情：

[NSObject cancelPreviousPerformRequestsWithTarget:self]; 

Answer 2

MKCoordinateRegion region = { {0.0, 0.0 }, { 0.0, 0.0 } }; 
region.center.latitude = Your Latitude ; 
region.center.longitude = Your Longitude; 
region.span.longitudeDelta = 0.01f; 
region.span.latitudeDelta = 0.01f; 
[map setRegion:region animated:YES]; 
[map addAnnotation:ann];