【Android】3.6 地图基本控制方法

分类：C#、Android、VS2015、百度地图应用； 创建日期：2016-02-04

一、简介

文件名：Demo05MapControl.cs

简介：介绍平移和缩放地图，双指操作地图，监听地图点击事件

详述：

（1）介绍地图缩放级别、旋转度和俯视度的get和set方法；

（2）监听单击和长按地图事件；

（3）单击、双击和长按地图获取该点的经纬度坐标；

（4）对地图显示内容进行截图，截图保存地址为：/mnt/sdcard/test.png；

运行截图

在x86模拟器中的运行效果如下：

二、设计步骤

1、添加demo06_mapcontrol.axml

在layout文件夹下添加该文件，将其改为下面的代码：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="50dip"
        android:orientation="horizontal" >

        <Button
            android:id="@+id/zoombutton"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:layout_weight=""
            android:text="缩放" />

        <EditText
            android:id="@+id/zoomlevel"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:layout_weight=""
            android:text="" />

        <Button
            android:id="@+id/rotatebutton"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:layout_weight=""
            android:text="旋转" />

        <EditText
            android:id="@+id/rotateangle"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:layout_weight=""
            android:text="" />

        <Button
            android:id="@+id/overlookbutton"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:layout_weight=""
            android:text="俯视" />

        <EditText
            android:id="@+id/overlookangle"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:layout_weight=""
            android:text="-30" />
    </LinearLayout>

    <TextView
        android:id="@+id/state"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:lines=""
        android:text="点击、长按、双击地图以获取经纬度和地图状态" />

    <RelativeLayout
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:orientation="vertical" >

        <com.baidu.mapapi.map.TextureMapView
            android:id="@+id/bmapView"
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:clickable="true" />

        <Button
            android:id="@+id/savescreen"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentRight="true"
            android:layout_alignParentTop="true"
            android:layout_marginTop="10dip"
            android:text="截图" />
    </RelativeLayout>

</LinearLayout>

2、添加Demo06MapControl.cs

在SrcSdkDemos文件夹下添加该文件，然后将其内容改为下面的代码：

using Android.App;
using Android.Content.PM;
using Android.Graphics;
using Android.OS;
using Android.Widget;
using Com.Baidu.Mapapi.Map;
using Com.Baidu.Mapapi.Model;
using System.IO;

namespace BdMapV371Demos.SrcSdkDemos
{
    /// <summary>
    /// 演示地图缩放，旋转，视角控制
    /// </summary>
    [Activity(Label = "@string/demo_name_control",
        ConfigurationChanges = ConfigChanges.Orientation | ConfigChanges.KeyboardHidden,
        ScreenOrientation = ScreenOrientation.Sensor)]
    public class Demo06MapControl : Activity,
        BaiduMap.IOnMapClickListener, BaiduMap.IOnMapLongClickListener,
        BaiduMap.IOnMapDoubleClickListener, BaiduMap.IOnMapStatusChangeListener,
        BaiduMap.ISnapshotReadyCallback
    {
        private TextureMapView mMapView;
        private BaiduMap mBaiduMap;

        /// <summary>
        /// 当前地点击点
        /// </summary>
        private LatLng currentPt;

        private string touchType;

        /// <summary>
        /// 用于显示地图状态的面板
        /// </summary>
        private TextView mStateBar;

        protected override void OnCreate(Bundle savedInstanceState)
        {
            base.OnCreate(savedInstanceState);
            SetContentView(Resource.Layout.demo06_mapcontrol);

            mMapView = FindViewById<TextureMapView>(Resource.Id.bmapView);
            mBaiduMap = mMapView.Map;
            mBaiduMap.SetMapStatus(MapStatusUpdateFactory.NewLatLng(MainActivity.HeNanUniversity));

            mStateBar = FindViewById<TextView>(Resource.Id.state);
            mBaiduMap.SetOnMapClickListener(this);
            mBaiduMap.SetOnMapLongClickListener(this);
            mBaiduMap.SetOnMapDoubleClickListener(this);
            mBaiduMap.SetOnMapStatusChangeListener(this);

            var btnZoom = FindViewById<Button>(Resource.Id.zoombutton);
            btnZoom.Click += delegate
            {
                //处理缩放 sdk 缩放级别范围： [3.0, 19.0]
                EditText t = FindViewById<EditText>(Resource.Id.zoomlevel);
                try
                {
                    float zoomLevel = float.Parse(t.Text);
                    MapStatusUpdate u = MapStatusUpdateFactory.ZoomTo(zoomLevel);
                    mBaiduMap.AnimateMapStatus(u);
                }
                catch
                {
                    Toast.MakeText(this, "请输入正确的缩放级别", ToastLength.Short).Show();
                }
                UpdateMapState();
            };

            var btnRotate = FindViewById<Button>(Resource.Id.rotatebutton);
            btnRotate.Click += delegate
            {
                //处理旋转。旋转角范围：-180～180 , 单位：度，逆时针旋转
                EditText t = FindViewById<EditText>(Resource.Id.rotateangle);
                try
                {
                    int rotateAngle = int.Parse(t.Text);
                    MapStatus ms = new MapStatus.Builder(mBaiduMap.MapStatus).Rotate(rotateAngle).Build();
                    MapStatusUpdate u = MapStatusUpdateFactory.NewMapStatus(ms);
                    mBaiduMap.AnimateMapStatus(u);
                }
                catch
                {
                    Toast.MakeText(this, "请输入正确的旋转角度", ToastLength.Short).Show();
                }
                UpdateMapState();
            };

            var btnOverlook = FindViewById<Button>(Resource.Id.overlookbutton);
            btnOverlook.Click += delegate
            {
                //处理俯视。俯角范围：-45～0, 单位：度
                EditText t = FindViewById<EditText>(Resource.Id.overlookangle);
                try
                {
                    int overlookAngle = int.Parse(t.Text);
                    MapStatus ms = new MapStatus.Builder(mBaiduMap.MapStatus).Overlook(overlookAngle).Build();
                    MapStatusUpdate u = MapStatusUpdateFactory.NewMapStatus(ms);
                    mBaiduMap.AnimateMapStatus(u);
                }
                catch
                {
                    Toast.MakeText(this, "请输入正确的俯角", ToastLength.Short).Show();
                }
                UpdateMapState();
            };

            var btnSaveScreen = FindViewById<Button>(Resource.Id.savescreen);
            btnSaveScreen.Click += delegate
            {
                // 截图（在SnapshotReadyCallback中保存图片到sd卡）
                mBaiduMap.Snapshot(this);
                Toast.MakeText(this, "正在截取屏幕图片...", ToastLength.Short).Show();
                UpdateMapState();
            };
        }

        #region 实现BaiduMap.IOnMapClickListener接口
        public void OnMapClick(LatLng p0)
        {
            touchType = "单击";
            currentPt = p0;
            UpdateMapState();
        }

        public bool OnMapPoiClick(MapPoi p0)
        {
            return false;
        }
        #endregion

        #region 实现BaiduMap.IOnMapLongClickListener接口
        public void OnMapLongClick(LatLng p0)
        {
            touchType = "长按";
            currentPt = p0;
            UpdateMapState();
        }
        #endregion

        #region 实现BaiduMap.IOnMapDoubleClickListener接口
        public void OnMapDoubleClick(LatLng p0)
        {
            touchType = "双击";
            currentPt = p0;
            UpdateMapState();
        }
        #endregion

        #region 实现BaiduMap.IOnMapStatusChangeListener接口
        public void OnMapStatusChange(MapStatus p0)
        {
            UpdateMapState();
        }

        public void OnMapStatusChangeFinish(MapStatus p0)
        {
            UpdateMapState();
        }

        public void OnMapStatusChangeStart(MapStatus p0)
        {
            UpdateMapState();
        }
        #endregion

        #region 实现BaiduMap.ISnapshotReadyCallback接口
        public void OnSnapshotReady(Bitmap p0)
        {
            string file = "/mnt/sdcard/test.png";
            FileStream outX;
            try
            {
                outX = new FileStream(file, FileMode.Create);
                if (p0.Compress(
                        Bitmap.CompressFormat.Png, , outX))
                {
                    outX.Flush();
                    outX.Close();
                }
                Toast.MakeText(this,
                        "屏幕截图成功，图片保存在: " + file.ToString(),
                        ToastLength.Short).Show();
            }
            catch (FileNotFoundException e)
            {
                throw e;
            }
            catch (IOException e)
            {
                throw e;
            }
        }
        #endregion

        /// <summary>
        /// 更新地图状态显示面板
        /// </summary>
        private void UpdateMapState()
        {
            if (mStateBar == null)
            {
                return;
            }
            string state = "";
            if (currentPt == null)
            {
                state = "点击、长按、双击地图以获取经纬度和地图状态";
            }
            else
            {
                state = string.Format(touchType + ",当前经度：{0:f6} 当前纬度：{1:f6}",
                        currentPt.Longitude, currentPt.Latitude);
            }
            state += "\n";
            MapStatus ms = mBaiduMap.MapStatus;
            state += string.Format("zoom={0:f2}，rotate={1:d}，overlook={2:d}",
                    ms.Zoom, (int)ms.Rotate, (int)ms.Overlook);
            mStateBar.Text = state;
        }

        protected override void OnPause()
        {
            mMapView.OnPause();
            base.OnPause();
        }

        protected override void OnResume()
        {
            mMapView.OnResume();
            base.OnResume();
        }

        protected override void OnDestroy()
        {
            mMapView.OnDestroy();
            base.OnDestroy();
        }
    }
}

3、修改MainActivity.cs

在MainActivity.cs文件的demos字段定义中添加下面的代码。

          //示例6--地图操作功能
            new DemoInfo<Activity>(Resource.String.demo_title_control,
                Resource.String.demo_desc_control,
                new Demo06MapControl()),

运行观察结果。