參考：http://www.reibang.com/p/4aa23d69d481

原文地址:https://mp.weixin.qq.com/s/d9QCoBP6kV9VSWvVldVVwA

public class DensityUtils {
    private static float sOriginalDensity;
    private static float sOriginalScaledDensity;
    private static int sOriginalDensityDpi;
    private static final int sTargetWidthDp = 360;
    private static float sCompatDensity;
    private static float sCompatScaledDensity;

    public static void init(Application application){
        final DisplayMetrics appDisplayMetrics = application.getResources().getDisplayMetrics();
        sOriginalDensity = appDisplayMetrics.density;
        sOriginalScaledDensity = appDisplayMetrics.scaledDensity;
        sOriginalDensityDpi = appDisplayMetrics.densityDpi;
        application.registerActivityLifecycleCallbacks(new Application.ActivityLifecycleCallbacks() {
            @Override
            public void onActivityCreated(Activity activity, Bundle savedInstanceState) {

                if(activity instanceof CameraIDActivity || activity instanceof CameraIDHandHoldActivity){
                    setsOriginalDensity(activity,application);
                }else{
                    setCustomDensity(activity,application);
                }
            }

            @Override
            public void onActivityStarted(Activity activity) {
            }

            @Override
            public void onActivityResumed(Activity activity) {
            }

            @Override
            public void onActivityPaused(Activity activity) {
            }

            @Override
            public void onActivityStopped(Activity activity) {
            }

            @Override
            public void onActivitySaveInstanceState(Activity activity, Bundle outState) {
            }

            @Override
            public void onActivityDestroyed(Activity activity) {
            }
        });
    }

    /**
     * 今日頭條適配
     * @param activity
     * @param application
     */
    private static void setCustomDensity(Activity activity, Application application) {
        final DisplayMetrics appDisplayMetrics = application.getResources().getDisplayMetrics();

        if (sCompatDensity == 0) {
            sCompatDensity = appDisplayMetrics.density;
            sCompatScaledDensity = appDisplayMetrics.scaledDensity;
            application.registerComponentCallbacks(new ComponentCallbacks() {
                @Override
                public void onConfigurationChanged(Configuration newConfig) {
                    if (newConfig != null && newConfig.fontScale > 0) {
                        sCompatScaledDensity = application.getResources().getDisplayMetrics().scaledDensity;
                    }
                }

                @Override
                public void onLowMemory() {
                }
            });
        }
        final float targetDensity = appDisplayMetrics.widthPixels / sTargetWidthDp;
        final float targetScaleDensity = targetDensity * (sCompatScaledDensity / sCompatDensity);
        final int targetDensityDpi = (int) (160 * targetDensity);
        appDisplayMetrics.density = targetDensity;
        appDisplayMetrics.scaledDensity = targetScaleDensity;
        appDisplayMetrics.densityDpi = targetDensityDpi;


        DisplayMetrics activityDisplayMetrics = activity.getResources().getDisplayMetrics();
        activityDisplayMetrics.density = targetDensity;
        activityDisplayMetrics.scaledDensity = targetScaleDensity;
        activityDisplayMetrics.densityDpi = targetDensityDpi;
    }

    /**
     * 還原原始Density
     * @param activity
     * @param application
     */
    public static void setsOriginalDensity(Activity activity, Application application) {
        final DisplayMetrics appDisplayMetrics = application.getResources().getDisplayMetrics();
        appDisplayMetrics.density = sOriginalDensity;
        appDisplayMetrics.scaledDensity = sOriginalScaledDensity;
        appDisplayMetrics.densityDpi = sOriginalDensityDpi;

        DisplayMetrics activityDisplayMetrics = activity.getResources().getDisplayMetrics();
        activityDisplayMetrics.density = sOriginalDensity;
        activityDisplayMetrics.scaledDensity = sOriginalScaledDensity;
        activityDisplayMetrics.densityDpi = sOriginalDensityDpi;
    }
}