Android

1、 获取经纬度高程

/**
  * 启动GPS传感器一次，用于获取位置、高程
  */
public void startLocationSensorOnce(Activity activity) {
    LocationManager locationManager;
    locationManager = (LocationManager) activity.getSystemService(Context.LOCATION_SERVICE);
    String locationProvider = null;
    //获取所有可用的位置提供器
    List<String> providers = locationManager.getProviders(true);
    if (providers.contains(LocationManager.GPS_PROVIDER)) {
        //如果是GPS
        locationProvider = LocationManager.GPS_PROVIDER;
    } else if (providers.contains(LocationManager.NETWORK_PROVIDER)) {
        //如果是Network
        locationProvider = LocationManager.NETWORK_PROVIDER;
    } else {
        System.out.println("----");
    }
    if (locationProvider != null) {
        if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
            System.out.println("没有权限");
            return;
        }
        Location location = locationManager.getLastKnownLocation(locationProvider);
        if(location == null){
            Toast.makeText(this,"无法获取位置",Toast.LENGTH_LONG).show();
        }else {
            Toast.makeText(this,"lon:"+location.getLongitude()+",lat:"+location.getLatitude()+",alt:"+location.getAltitude(),Toast.LENGTH_LONG).show();
        }
    }
}

2、SQLite

• DatabaseHelper

public class DatabaseHelper extends SQLiteOpenHelper {
    public DatabaseHelper(Context context){
        super(context,"test1.db",null,1);
    }
    /**
     * 建表
     */
    @Override
    public void onCreate(SQLiteDatabase db) {
        db.execSQL("CREATE TABLE information(\n" +
                "             id INTEGER PRIMARY KEY NOT NULL,\n" +
                "             name TEXT NOT NULL" +
                "             )");
        db.execSQL("INSERT into information(id,name) VALUES (202001,\"张三\");");
        db.execSQL("INSERT into information(id,name) VALUES (202002,\"王乐\",\"男\");");
        db.execSQL("INSERT into information(id,name) VALUES (202003,\"刘小慧\");");
    }
    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
    }
}

• Test

private void insertDb(){
    ContentValues values=new ContentValues();
    values.put("id","10004");
    values.put("name","testInsert");
    writableDatabase.insert("information",null,values);
    System.out.println("数据插入成功");
}
private void queryDb(){
    Cursor cursor = writableDatabase.rawQuery("select * from information where id = ?",new String[]{"10004"});
    // //判断结果集中是否有数据，有：查询成功；无：查询失败
    if(cursor.getCount()!=0){
        //循环遍历结果集，取出数据，显示出来
        while (cursor.moveToNext()){
            String id = cursor.getString(cursor.getColumnIndex("id"));
            String name = cursor.getString(cursor.getColumnIndex("name"));
            System.out.println(id+"--"+name);
        }
    }
    cursor.close();
}
private void updateDb(){
    ContentValues values=new ContentValues();
    values.put("name","666");
    writableDatabase.update("information",values,"id=?",new String[]{"10004"});
    System.out.println("数据更新成功");
}
private void deleteDb(){
    writableDatabase.delete("information","id=?",new String[]{"10004"});
    System.out.println("数据删除成功");
}

保存图片

• DatabaseHelper

@Override
public void onCreate(SQLiteDatabase db) {
    db.execSQL("CREATE TABLE information(\n" +
               "             id INTEGER PRIMARY KEY NOT NULL,\n" +
               "             name TEXT NOT NULL,\n" +
               "             images BLOB"+
               "             )");
}

• Test

private ImageView showIcon; 
showIcon = findViewById(R.id.imageView);
private void insertDb(){
    ContentValues values=new ContentValues();
    InputStream open = null;
    ByteArrayOutputStream os = null;
    try {
        open = this.getAssets().open("test.jpg");
        os = new ByteArrayOutputStream();
        IoUtil.copy(open,os);
        values.put("id","10004");
        values.put("name","testInsert");
        values.put("images",os.toByteArray());
        writableDatabase.insert("information",null,values);
        System.out.println("数据插入成功");
    }catch (IOException e){
        e.printStackTrace();
    }finally {
        try {
            if(os != null){
                os.close();
            }
            if(open != null){
                open.close();
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}
private void queryDb(){
    Cursor cursor = writableDatabase.rawQuery("select * from information where id = ?",new String[]{"10004"});
    // //判断结果集中是否有数据，有：查询成功；无：查询失败
    if(cursor.getCount()!=0){
        //循环遍历结果集，取出数据，显示出来
        while (cursor.moveToNext()){
            String id = cursor.getString(cursor.getColumnIndex("id"));
            String name = cursor.getString(cursor.getColumnIndex("name"));
            byte[] in = cursor.getBlob(cursor.getColumnIndex("images"));
            Bitmap bit = BitmapFactory.decodeByteArray(in, 0, in.length);
            showIcon.setImageBitmap(bit);
            System.out.println(id+"--"+name);
        }
    }
    cursor.close();
}