Utils.java

package de.devland.masterpassword.base.util;

import android.content.Context;
import android.content.res.Resources;
import android.graphics.drawable.Drawable;
import android.support.annotation.ColorRes;
import android.support.v4.content.ContextCompat;
import android.support.v4.graphics.drawable.DrawableCompat;
import android.support.v7.app.AppCompatDelegate;
import android.util.DisplayMetrics;
import android.widget.ImageView;

/**
 * Created by deekay on 27/02/15.
 */
public class Utils {
    /**
     * 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 * (metrics.densityDpi / 160f);
        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 / (metrics.densityDpi / 160f);
        return dp;
    }

    public static void setThemeModeFromName(String themeMode) {
        switch (themeMode) {
            case ThemeMode.LIGHT:
                AppCompatDelegate.setDefaultNightMode(AppCompatDelegate.MODE_NIGHT_NO);
                break;
            case ThemeMode.DARK:
                AppCompatDelegate.setDefaultNightMode(AppCompatDelegate.MODE_NIGHT_YES);
                break;
            case ThemeMode.AUTO:
                AppCompatDelegate.setDefaultNightMode(AppCompatDelegate.MODE_NIGHT_AUTO);
                break;
        }
    }

    public static void tint(Context context, ImageView imageView, @ColorRes int tint) {
        Drawable wrapped = DrawableCompat.wrap(imageView.getDrawable());
        DrawableCompat.setTint(wrapped, ContextCompat.getColor(context, tint));
        imageView.setImageDrawable(wrapped);
    }

    public interface ThemeMode {
        String DARK = "DARK";
        String LIGHT = "LIGHT";
        String AUTO = "AUTO";
    }

}