px、dp、sp转换

public class DensityUtil {

	public static int px2dp(Context context, float pxValue) {
		final float scale = context.getResources().getDisplayMetrics().density;
		return (int) (pxValue / scale + 0.5f);
	}

	public static int dp2px(Context context, float dpValue) {
		final float scale = context.getResources().getDisplayMetrics().density;
		return (int) (dpValue * scale + 0.5f);
	}

	public static int px2sp(Context context, float pxValue) {
		final float fontScale = context.getResources().getDisplayMetrics().scaledDensity;
		return (int) (pxValue / fontScale + 0.5f);
	}

	public static int sp2px(Context context, float spValue) {
		final float fontScale = context.getResources().getDisplayMetrics().scaledDensity;
		return (int) (spValue * fontScale + 0.5f);
	}
}