1. 120dpi(ldpi低密度屏)，160dpi(mdpi中密度屏)，213dpi(tvdpi电视密度屏)，240dpi(hdpi高密度屏)，320dpi(xhdpi极高密度屏)；

2. 限定符(land,port)可以帮助我们区分屏幕横竖屏状态

• values-land-ldpi
• values-land-hdpi
• values-land-hdpi-800x480-4.0
• values-land-mdpi-800x480-5.1
• values-land-mdpi-854x480-5.4
• values-land-mdpi-1024x600-7.0
• values-land-mdpi-1280x800-10.1
• values-land-xhpdi-1280x768-4
• values-land-xhpdi-1280x720-4.7
• values-land-xhpdi-1920x1200-7
• values-land-xhpdi-2560x1600-10
• values-land-tvpdi-1280x800-7
• values-land-xxhdpi-1920x1080-5
• values-port-ldpi
• values-port-hdpi
• values-port-hdpi-800x480-4.0
• values-port-mdpi-800x480-5.1
• values-port-mdpi-854x480-5.4
• values-port-mdpi-1024x600-7.0
• values-port-mdpi-1280x800-10.1
• values-port-xhpdi-1280x768-4
• values-port-xhpdi-1280x720-4.7
• values-port-xhpdi-1920x1200-7
• values-port-xhpdi-2560x1600-10
• values-port-tvpdi-1280x800-7
• values-port-xxhdpi-1920x1080-5

参考