Android Question DevicePhysicalSize maybe incorrect ?

[little3399]

Hi ,

I found the DevicePhysicalSize seem maybe incorrect , here is my code and the result :

my code:
Dim lv As LayoutValues

lv = GetDeviceLayoutValues
Label1.Text="ApproximateScreenSize:"
Label2.Text=lv.ApproximateScreenSize
Label3.Text="Scale:"
Label4.Text=lv.Scale
Label5.Text="Height:"
Label6.Text=lv.Height
Label7.Text="Width:"
Label8.Text=lv.Width
Label9.Text="DevicePhysicalSize:"
Label10.Text=Scale.GetDevicePhysicalSize

result:

My question is they are all correct ?

 

[Erel]

It is the same as GetDeviceLayoutValues.ApproximateScreenSize. As it name suggests this is an approximation based on the reported dimensions.

It is based on Pythagoras theorem:
Size = ((Width / 160 / Scale) ^ 2 + (Height / 160 / Scale) ^ 2) ^ 0.5

It is an approximation because the scale is not exact.

 

[little3399]

Tks ,I knowed

 

[little3399]

Is there exist a simple way or formula to caluate a dip unit length?

 

[klaus]

dips are based on the 'standard' resolution of 160 dpi (dots per inch)
so 1 dip = 1'' / 160 = 0.00625''
or 25.4 / 160 = 0.159mm

 

[little3399]

24.5/160 ，24.5 on behalf of what? TKS!

 

[klaus]

24.5 should be 25.4
1 inch = 25.4 mm (millimeters).

 

[little3399]

Tks ! Klaus

 

[Erel]

Note that you can get the exact scale values with the code posted here: http://www.b4x.com/android/forum/threads/same-physical-display-size.14037/#post-79434 (as reported by the device).