Programmatically set height on LayoutParams as density-independent pixels

Question

You need to convert your dip value into pixels:

int height = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, <HEIGHT>, getResources().getDisplayMetrics());

For me this does the trick.

 public static int getDPI(int size, DisplayMetrics metrics){
     return (size * metrics.densityDpi) / DisplayMetrics.DENSITY_DEFAULT;        
 }

Call the function like this,

DisplayMetrics metrics;
metrics = new DisplayMetrics();         
getWindowManager().getDefaultDisplay().getMetrics(metrics);

int heigh = getDPI(height or width, metrics);

Since it may be used multiple times:

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

I found it more practical to use the conversion rate, as usally more than one value has to be converted. Since the conversion rate does not change, it saves a bit of processing time.

/**
 * Get conversion rate from dp into px.<br>
 * E.g. to convert 100dp: px = (int) (100 * convRate);
 * @param context e.g. activity
 * @return conversion rate
 */
public static float convRateDpToPx(Context context) {
    return context.getResources().getDisplayMetrics().densityDpi / 160f;
}

Here is my snippet:

public class DpiUtils {

    public static int toPixels(int dp, DisplayMetrics metrics) {
        return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dp, metrics);
    }

}

where DisplayMetrics metrics = getResources().getDisplayMetrics()