Android Width – Does setWidth(int pixels) Use DIP or PX

androiddensity-independent-pixelpixelunits-of-measurementwidth

Does setWidth(int pixels) use device independent pixel or physical pixel as unit?
For example, does setWidth(100) set the a view's width to 100 dips or 100 pxs?

Thanks.

Best Answer

It uses pixels, but I'm sure you're wondering how to use dips instead. The answer is in TypedValue.applyDimension(). Here's an example of how to convert dips to px in code:

// Converts 14 dip into its equivalent px
Resources r = getResources();
int px = Math.round(TypedValue.applyDimension(
    TypedValue.COMPLEX_UNIT_DIP, 14,r.getDisplayMetrics()));

Related Solutions

Android Layout – Understanding Relations Between dip, px, and dpi

That question is fully covered by official documentation. Relations between dip, px and dpi are covered by this section.

Quote:

Density-independent pixel (dp)

A virtual pixel unit that applications can use in defining their UI, to express layout dimensions or position in a density-independent way.

The density-independent pixel is equivalent to one physical pixel on a 160 dpi screen, the baseline density assumed by the platform (as described later in this document). At run time, the platform transparently handles any scaling of the dp units needed, based on the actual density of the screen in use. The conversion of dp units to screen pixels is simple: pixels = dps * (density / 160). For example, on 240 dpi screen, 1 dp would equal 1.5 physical pixels. Using dp units to define your application's UI is highly recommended, as a way of ensuring proper display of your UI on different screens.

So the statement:

that always be 12px in mdpi and so 18px in hdpi

seems to be correct, according to the docs.

Android – Convert DIP to PX

Try this:

Java

public static float dipToPixels(Context context, float dipValue) {
    DisplayMetrics metrics = context.getResources().getDisplayMetrics();
    return TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dipValue, metrics);
}

Kotlin

fun Context.dipToPixels(dipValue: Float) =
    TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dipValue, resources.displayMetrics)

Best Answer

Related Solutions

Android Layout – Understanding Relations Between dip, px, and dpi

Android – Convert DIP to PX

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