您应该使用animateToRegion方法（请参见此处）
它采用一个区域对象，该对象具有latitudeDelta和longitudeDelta。使用这些设置缩放级别。

• • 更新日期：**

在Region对象中，latitude和longitude指定中心位置，而latitudeDelta和longitudeDelta指定可视Map区域的跨度。
这张来自this博客文章的图片很好地说明了这一点（Lat Δ和Lng Δ）。

新的React Native Maps API为您提供了使用zoom参数调用animateCamera方法的选项。

const MapComponent= (props: any) => {

const map: LegacyRef<MapView> = useRef(null);

const onZoomInPress = () => {
    map?.current?.getCamera().then((cam: Camera) => {
        cam.zoom += 1;
        map?.current?.animateCamera(cam);
    });
};

return (
        <View>
            <MapView
                ref={map}
                provider={PROVIDER_GOOGLE}
                region={region}>
            </MapView>
            <ButtonComponent
                style={{position: 'absolute', bottom: 400, left: 0}}
                onPress={onZoomInPress}>
                Zoom In
            </MainButtonBlue>
        </View>
    );
}

我可以使用Dimensions.get('window');完成此工作

const window = Dimensions.get('window');
            const { width, height }  = window
            LONGITUDE_DELTA = LATITUD_DELTA + (width / height)

并且默认设置为LATITUD_DELTA = 0.0922。然后只需使用<MapView>中的属性onRegionChangeComplete更新此值

这就是我所做的，而且效果很好：

function getRegion(origin, destination, zoom) {
  const oLat = Math.abs(origin.latitude);
  const oLng = Math.abs(origin.longitude);
  const dLat = Math.abs(destination.latitude);
  const dLng = Math.abs(destination.longitude);

  return {
      latitude: (origin.latitude + destination.latitude) / 2,
      longitude: (origin.longitude + destination.longitude) / 2,
      latitudeDelta: Math.abs(oLat - dLat) + zoom,
      longitudeDelta: Math.abs(oLng - dLng) + zoom,
  };                                                                                  
}

我基于https://github.com/tuupola/php_google_maps中的墨卡托数学创建了以下内容
键函数为mercatorDegreeDeltas(latitude, longitude, width, height, zoom)，它返回指定纬度/经度中心点、Map尺寸和缩放级别（1-20）的{ latitudeDelta, longitudeDelta }。

import React from 'react';
import { useWindowDimensions } from 'react-native';
import MapView from 'react-native-maps';
import { useBottomTabBarHeight } from '@react-navigation/bottom-tabs';
import { useHeaderHeight } from '@react-navigation/elements';

const MERCATOR_OFFSET = Math.pow(2, 28);
const MERCATOR_RADIUS = MERCATOR_OFFSET / Math.PI;

function mercatorLatitudeToY(latitude) {
  return Math.round(
    MERCATOR_OFFSET - 
    (
      (
        MERCATOR_RADIUS *
          Math.log(
            (1 + Math.sin(latitude * (Math.PI / 180))) /
            (1 - Math.sin(latitude * (Math.PI / 180)))
          )
      ) / 2
    )
  );
}

function mercatorLongitudeToX(longitude) {
  return Math.round(
    MERCATOR_OFFSET +
      (
        (
          (MERCATOR_RADIUS * longitude) * Math.PI
        ) / 180
      )
  );
}

function mercatorXToLongitude(x) {
  return (
    (
      (x - MERCATOR_OFFSET) / MERCATOR_RADIUS
    ) * 180
  ) / Math.PI;
}

function mercatorYToLatitude(y) {
  return (
    (
      (
        Math.PI / 2
      ) -
        (2 * Math.atan(
              Math.exp(
                (
                  y - MERCATOR_OFFSET
                ) / MERCATOR_RADIUS
              )
            )
        )
    ) * 180
  ) / Math.PI;
}

function mercatorAdjustLatitudeByOffsetAndZoom(latitude, offset, zoom) {
  return mercatorYToLatitude(mercatorLatitudeToY(latitude) + (offset << (21 - zoom)));
}

function mercatorAdjustLongitudeByOffsetAndZoom(longitude, offset, zoom) {
  return mercatorXToLongitude(mercatorLongitudeToX(longitude) + (offset << (21 - zoom)));
}

function mercatorDegreeDeltas(latitude, longitude, width, height, zoom) {

  if (!zoom) {
    zoom = 20;
  }

  const deltaX = width / 2;
  const deltaY = height / 2;

  const northLatitude = mercatorAdjustLatitudeByOffsetAndZoom(latitude, deltaY * -1, zoom);
  const westLongitude = mercatorAdjustLongitudeByOffsetAndZoom(longitude, deltaX * -1, zoom);
  const southLatitude = mercatorAdjustLatitudeByOffsetAndZoom(latitude, deltaY, zoom);
  const eastLongitude = mercatorAdjustLongitudeByOffsetAndZoom(longitude, deltaY, zoom);

  const latitudeDelta = Math.abs(northLatitude - southLatitude);
  const longitudeDelta = Math.abs(eastLongitude - westLongitude);

  return { latitudeDelta, longitudeDelta };
}

// Somewhat arbitrarily, Riverside Park, Independence, KS 67301
const CENTER_UNITED_STATES = {
  latitude: 37.24435373025407,
  longitude: -95.70234410503208,
};

export default function MapViewWrapper() {
  const { width, height } = useWindowDimensions();
  const tabBarHeight = useBottomTabBarHeight();
  const headerHeight = useHeaderHeight();
  const initialRegion = React.useRef(null);
  const availableHeight = height - tabBarHeight - headerHeight;

  // Only calculate initial region once
  if (!initialRegion.current) {
    const { latitudeDelta, longitudeDelta } = mercatorDegreeDeltas(
      CENTER_UNITED_STATES.latitude,
      CENTER_UNITED_STATES.longitude,
      width,
      availableHeight,
      4,
    );
    
    initialRegion.current = {
      latitude: CENTER_UNITED_STATES.latitude,
      longitude: CENTER_UNITED_STATES.longitude,
      latitudeDelta: latitudeDelta,
      longitudeDelta: longitudeDelta,
    };
  }

  return (
    <MapView
      initialRegion={initialRegion.current}
      style={{ width: width, height: availableHeight }}
    />
  );
}

至少有一个问题：如果你把缩放比例从4改为3，它不能正确居中，但是更大的缩放值可以工作。我现在不需要更小的缩放值，所以我没有进一步研究数学（可能是某种溢出？）

//Example of Pinch to Zoom Image in React Native
//https://aboutreact.com/react-native-pinch-to-zoom-image/

//import React in our code
import React from 'react';

//import all the components we are going to use
import { SafeAreaView, StyleSheet, View } from 'react-native';

//import ImageViewer which will help us to zoom Image
import ImageViewer from 'react-native-image-zoom-viewer';

const App = () => {
  const images = [
    {
      url:
        'https://raw.githubusercontent.com/AboutReact/sampleresource/master/sample_img.png',
    },
    {
      url:
        'https://raw.githubusercontent.com/AboutReact/sampleresource/master/old_logo.png',
    },
  ];

  return (
    <SafeAreaView style={{ flex: 1 }}>
      <View style={styles.container}>
        <ImageViewer imageUrls={images} renderIndicator={() => null} />
      </View>
    </SafeAreaView>
  );
};

const styles = StyleSheet.create({
  container: {
    backgroundColor: '#F5FCFF',
    flex: 1,
  },
});

export default App;