MKMapRect zooms too much

Question

I use this code to show all my annotations on my map:

 MKMapRect zoomRect = MKMapRectNull;
        for (id  annotation in mapView.annotat         


        

Answer 1

Ariel's answer didn't work for me, but I made a few small changes to it and it's working great now (especially with maps with a single pin):

double minimumZoom = 6000; // for my purposes the width/height have same min zoom
BOOL needChange = NO;

double x = MKMapRectGetMinX(zoomRect);
double y = MKMapRectGetMinY(zoomRect);
double w = MKMapRectGetWidth(zoomRect);
double h = MKMapRectGetHeight(zoomRect);
double centerX = MKMapRectGetMidX(zoomRect);
double centerY = MKMapRectGetMidY(zoomRect);

if (h < minimumZoom) {  // no need to call MKMapRectGetHeight again; we just got its value!
    // get the multiplicative factor used to scale old height to new,
    // then apply it to the old width to get a proportionate new width
    double factor = minimumZoom / h;
    h = minimumZoom;
    w *= factor;
    x = centerX - w/2;
    y = centerY - h/2;
    needChange = YES;
}

if (w < minimumZoom) {
    // since we've already adjusted the width, there's a chance this
    // won't even need to execute
    double factor = minimumZoom / w;
    w = minimumZoom;
    h *= factor;
    x = centerX - w/2;
    y = centerY - h/2;
    needChange = YES;
}

if (needChange) {
    zoomRect = MKMapRectMake(x, y, w, h);
}

[mapView setVisibleMapRect:zoomRect animated:YES];