Converter.java

import android.content.Context;
import android.content.res.Resources;
import android.util.DisplayMetrics;


public class Converter {

    /**
     * This method converts dp unit to equivalent pixels, depending on device density.
     *
     * @param dp      A value in dp (density independent pixels) unit. Which we need to convert into pixels
     * @param context Context to get resources and device specific display metrics
     * @return A float value to represent px equivalent to dp depending on device density
     */
    public static float convertDpToPixel(float dp, Context context) {
        Resources resources = context.getResources();
        DisplayMetrics metrics = resources.getDisplayMetrics();
        float px = dp * ((float) metrics.densityDpi / DisplayMetrics.DENSITY_DEFAULT);
        return px;
    }

    /**
     * This method converts device specific pixels to density independent pixels.
     *
     * @param px      A value in px (pixels) unit. Which we need to convert into db
     * @param context Context to get resources and device specific display metrics
     * @return A float value to represent dp equivalent to px value
     */
    public static float convertPixelsToDp(float px, Context context) {
        Resources resources = context.getResources();
        DisplayMetrics metrics = resources.getDisplayMetrics();
        float dp = px / ((float) metrics.densityDpi / DisplayMetrics.DENSITY_DEFAULT);
        return dp;
    }

    public static String convertTimeToString(Context context, int hours, int minutes) {
        return context.getResources().getString(R.string.format_time_hour_minutes, hours, minutes);
//<string name="format_time_hour_minutes">%1$02d:%2$02d</string>
    }
}