Different Text Size under same screen resolution but different dpi in two Android machines

I have two Android machines - Samsung Galaxy Tab and HTC Flyer. They both have 1024x600 screen. However Tab has 240dpi screen while Flyer has 160dpi according to the log from Context.getResources().getDisplayMetrics() method.

My problem is that, I have a TextView defined, and according to those Android document, using unit of dp should give same physical size under different screen density(dpi). But what I observed is that, the text size appeared in Flyer is obviously smaller than that in Tab, no开发者_StackOverflow社区 luck in using sp too. I want them to be in same size. Any clue in solving this problem in general?

Thanks in advance.

Well, the reported values are clearly a lie. I suppose the Galaxy Tab is the 7in model. This means that, based on the reported values, it has about 4.2in display height (1024 / 240 = 4.2in) and about 2.5in width. This means that the screen size would be 4.2x2.5 in - and in this case the diagonal would be about 4.9in. Is it correct - no it isn't, it has 7in display. Measure the sides of the screen and you would get the correct density. So, even when scaled by Android the result will be wrong because of the false density measurement.

Anyway, the answer of the question is:

No, no way to draw same-sized fonts, images and whatever. You need to get used to false metrics from the manufacturer. A false density reading reflects on all other scaling. Thus even mm/in would not help.

And one advise - don't try to match sizes between different products, unless absolutely necessary. If you succeed, then the text on the Galaxy Tab, for example, will look disproportional in regards to the other text on the device and will make your app look out-of-place. Stick to the Android textAppearanceSmall/Large, etc.

Please try the following units:

mm

Millimeters - based on the physical size of the screen.

in

Inches - based on the physical size of the screen.

http://developer.android.com/guide/topics/resources/more-resources.html