[Android]第一行代码的参考代码

跟着郭老师的第一行代码做了一个漫长的实验，以下代码参考至《第一行代码》。

package com.example.lbstest;

import android.Manifest;
import android.content.pm.PackageManager;
import android.os.Bundle;
import android.view.Window;
import android.widget.TextView;
import android.widget.Toast;

import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import androidx.core.app.ActivityCompat;
import androidx.core.content.ContextCompat;

import com.baidu.location.BDLocation;
import com.baidu.location.BDLocationListener;
import com.baidu.location.LocationClient;
import com.baidu.location.LocationClientOption;
import com.baidu.mapapi.CoordType;
import com.baidu.mapapi.SDKInitializer;
import com.baidu.mapapi.map.BaiduMap;
import com.baidu.mapapi.map.BitmapDescriptor;
import com.baidu.mapapi.map.MapStatusUpdate;
import com.baidu.mapapi.map.MapStatusUpdateFactory;
import com.baidu.mapapi.map.MapView;
import com.baidu.mapapi.map.MyLocationData;
import com.baidu.mapapi.model.LatLng;

import java.util.ArrayList;
import java.util.List;

public class MainActivity extends AppCompatActivity {

    public LocationClient mLocationClient;

    private TextView positionText;

    private StringBuilder currentPosition;

    private MapView mapView;

    private BaiduMap baiduMap;

    private boolean isFirstLocate = true;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        mLocationClient = new LocationClient(getApplicationContext());
        mLocationClient.registerLocationListener(new MyLocationListener());
        SDKInitializer.initialize(getApplicationContext());
        setContentView(R.layout.activity_main);
        positionText = (TextView)findViewById(R.id.positiontext) ;
        mapView = (MapView) findViewById(R.id.bdmapview);
        baiduMap = mapView.getMap();
        baiduMap.setMyLocationEnabled(true);
        List permissionList = new ArrayList<>();
        if (ContextCompat.checkSelfPermission(MainActivity.this,
                Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
            permissionList.add(Manifest.permission.ACCESS_FINE_LOCATION);
        }
        if (ContextCompat.checkSelfPermission(MainActivity.this,
                Manifest.permission.READ_PHONE_STATE) != PackageManager.PERMISSION_GRANTED) {
            permissionList.add(Manifest.permission.READ_PHONE_STATE);
        }
        if (ContextCompat.checkSelfPermission(MainActivity.this,
                Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {
            permissionList.add(Manifest.permission.WRITE_EXTERNAL_STORAGE);
        }

        if (!permissionList.isEmpty()) {
            String[] permissions = permissionList.toArray(new String[permissionList.size()]);
            ActivityCompat.requestPermissions(MainActivity.this, permissions, 1);
        } else {
            requestLocation();
        }
    }

    private void requestLocation() {
        initLocation();
        mLocationClient.start();
    }

    private void initLocation() {
        LocationClientOption option = new LocationClientOption();
        option.setLocationMode(LocationClientOption.LocationMode.Hight_Accuracy);
        option.setScanSpan(5000);
        option.setIsNeedAddress(true);
        mLocationClient.setLocOption(option);
    }


    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        switch (requestCode) {
            case 1:
                if (grantResults.length > 0) {
                    for (int result : grantResults) {
                        if (result != PackageManager.PERMISSION_GRANTED) {
                            Toast.makeText(this, "必须同意所有权限才能使用本程序", Toast.LENGTH_SHORT).show();
                            finish();
                            return;
                        }
                    }
                    requestLocation();
                } else {
                    Toast.makeText(this, "发生未知错误", Toast.LENGTH_SHORT).show();
                    finish();
                }
                break;
            default:
        }
    }

    private void navigateTo(BDLocation location) {
        if (isFirstLocate) {
            LatLng ll = new LatLng(location.getLatitude(), location.getLongitude());
            MapStatusUpdate update = MapStatusUpdateFactory.newLatLng(ll);
            baiduMap.animateMapStatus(update);
            update = MapStatusUpdateFactory.zoomTo(16f);
            baiduMap.animateMapStatus(update);
            isFirstLocate = false;
        }
        MyLocationData.Builder locationBuilder = new MyLocationData.Builder();
        locationBuilder.latitude(location.getLatitude());
        locationBuilder.longitude(location.getLongitude());
        MyLocationData locationdata = locationBuilder.build();
        baiduMap.setMyLocationData(locationdata);
    }

    public class MyLocationListener implements BDLocationListener {

        @Override
        public void onReceiveLocation(BDLocation location) {
            if (location.getLocType() == BDLocation.TypeGpsLocation || location.getLocType() == BDLocation.TypeNetWorkLocation) {
                navigateTo(location);
            }
            currentPosition = new StringBuilder();
            currentPosition.append("纬度:").append(location.getLatitude()).append("\n");
            currentPosition.append("经度:").append(location.getLongitude()).append("\n");
            currentPosition.append("国家:").append(location.getCountry()).append("\n");
            currentPosition.append("省:").append(location.getProvince()).append("\n");
            currentPosition.append("市:").append(location.getCity()).append("\n");
            currentPosition.append("区:").append(location.getDistrict()).append("\n");
            currentPosition.append("街道:").append(location.getStreet()).append("\n");
            currentPosition.append("定位方式：");
            if (location.getLocType() == BDLocation.TypeGpsLocation) {
                currentPosition.append("GPS");
            } else if (location.getLocType() == BDLocation.TypeNetWorkLocation) {
                currentPosition.append("网络");
            }
            runOnUiThread(new Runnable() {
                @Override
                public void run() {
                    positionText.setText(currentPosition);
                }
            });
        }

    }

    @Override
    protected void onResume() {
        super.onResume();
        mapView.onResume();
    }

    @Override
    protected void onPause() {
        super.onPause();
        mapView.onPause();
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        mLocationClient.stop();
        mapView.onDestroy();
        baiduMap.setMyLocationEnabled(false);
    }
}