Merge pull request #16 from heyongjian/master

Merge pull request #31 from lwanghaol/master
Merge pull request #17 from heyongjian/master

merger
wanghao:doubleNumberPickerPreference compatible with different version
Merge pull request #33 from lwanghaol/master

Merge pull request #16 from heyongjian/master
weather the widget is added by menu
Merge pull request #35 from lwanghaol/master

weather the widget is added by menu
Merge pull request #27 from heyongjian/master

huangming:merge the main branch to native branch.