注：这个idea出自知乎某个回答，但是来源找不到了。。。工具是自己写的。

在项目开发中，UI给过来的设计图上的尺寸标识，一般以px(像素)为单位。Android工程师需根据设计图的尺寸将px换成dp，填到layout.xml中。

有了这个工具，可以很方便地实现这一点。

首先，确认设计图属于下列哪种规格：

ldpi (low) ~120dpi

mdpi (medium) ~160dpi

hdpi (high) ~240dpi

xhdpi (extra-high) ~320dpi

xxhdpi (extra-extra-high) ~480dpi

xxxhdpi (extra-extra-extra-high) ~640dpi

然后安装python，运行一个脚本：

import argparse

g_type_scale_dict = {

"mdpi": 1,

"hdpi": 0.67,

"xhdpi": 0.5,

"xxhdpi": 0.33,

"xxxhdpi": 0.25

}

def main(start, end, device_type):

if device_type not in g_type_scale_dict:

print "invaild device_type", device_type

return

scale = g_type_scale_dict[device_type]

print("")

for i in range(start, end+1):

print('%.1fdp' % (i, i*scale))

print("")

for i in range(start, end+1):

print('%.1fsp' % (i, i*scale))

if __name__ == "__main__":

parser = argparse.ArgumentParser()

parser.add_argument(dest="start", type=int)

parser.add_argument(dest="end", type=int)

parser.add_argument(dest="device_type")

args = parser.parse_args()

main(args.start, args.end, args.device_type)

然后在控制台中输入：

python dp_convertor.py 1 100 xxhdpi

可得到：

0.3dp

0.7dp

1.0dp

1.3dp

1.7dp

2.0dp

2.3dp

2.6dp

3.0dp

3.3dp

3.6dp

4.0dp

4.3dp

4.6dp

5.0dp

5.3dp

5.6dp

5.9dp

6.3dp

6.6dp

6.9dp

7.3dp

7.6dp

7.9dp

8.2dp

8.6dp

8.9dp

9.2dp

9.6dp

9.9dp

10.2dp

10.6dp

10.9dp

11.2dp

11.6dp

11.9dp

12.2dp

12.5dp

12.9dp

13.2dp

13.5dp

13.9dp

14.2dp

14.5dp

14.9dp

15.2dp

15.5dp

15.8dp

16.2dp

16.5dp

16.8dp

17.2dp

17.5dp

17.8dp

18.2dp

18.5dp

18.8dp

19.1dp

19.5dp

19.8dp

20.1dp

20.5dp

20.8dp

21.1dp

21.4dp

21.8dp

22.1dp

22.4dp

22.8dp

23.1dp

23.4dp

23.8dp

24.1dp

24.4dp

24.8dp

25.1dp

25.4dp

25.7dp

26.1dp

26.4dp

26.7dp

27.1dp

27.4dp

27.7dp

28.1dp

28.4dp

28.7dp

29.0dp

29.4dp

29.7dp

30.0dp

30.4dp

30.7dp

31.0dp

31.4dp

31.7dp

32.0dp

32.3dp

32.7dp

33.0dp

0.3sp

0.7sp

1.0sp

1.3sp

1.7sp

2.0sp

2.3sp

2.6sp

3.0sp

3.3sp

3.6sp

4.0sp

4.3sp

4.6sp

5.0sp

5.3sp

5.6sp

5.9sp

6.3sp

6.6sp

6.9sp

7.3sp

7.6sp

7.9sp

8.2sp

8.6sp

8.9sp

9.2sp

9.6sp

9.9sp

10.2sp

10.6sp

10.9sp

11.2sp

11.6sp

11.9sp

12.2sp

12.5sp

12.9sp

13.2sp

13.5sp

13.9sp

14.2sp

14.5sp

14.9sp

15.2sp

15.5sp

15.8sp

16.2sp

16.5sp

16.8sp

17.2sp

17.5sp

17.8sp

18.2sp

18.5sp

18.8sp

19.1sp

19.5sp

19.8sp

20.1sp

20.5sp

20.8sp

21.1sp

21.4sp

21.8sp

22.1sp

22.4sp

22.8sp

23.1sp

23.4sp

23.8sp

24.1sp

24.4sp

24.8sp

25.1sp

25.4sp

25.7sp

26.1sp

26.4sp

26.7sp

27.1sp

27.4sp

27.7sp

28.1sp

28.4sp

28.7sp

29.0sp

29.4sp

29.7sp

30.0sp

30.4sp

30.7sp

31.0sp

31.4sp

31.7sp

32.0sp

32.3sp

32.7sp

33.0sp

将以上复制到你项目的dimens.xml中，以后可以直接按照设计图的px值，在layout.xml中写@dimen/_**px了。