沉浸式（透明+隐藏）

Activity

package com.zjc.immersivetest;

import android.graphics.Color;
import android.os.Build;
import android.support.v7.app.ActionBar;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;

import static android.view.View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION;

public class MainActivity extends AppCompatActivity {

    /**
     *
     *  实现标准沉浸式状态
     */
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        if (Build.VERSION.SDK_INT >= 21) {  //当系统版本大于5.0时执行
        View decorView = getWindow().getDecorView();
        int option = View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
                | View.SYSTEM_UI_FLAG_LAYOUT_STABLE //两个FLAG一起用表示会让应用的主体内容占用系统状态栏的空间
                | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION;    //让应用的主体内容占用系统导航栏的空间
        decorView.setSystemUiVisibility(option);
        getWindow().setNavigationBarColor(Color.TRANSPARENT);   //设置导航栏透明
        getWindow().setStatusBarColor(Color.TRANSPARENT);   //设置状态栏透明
    }
    ActionBar actionBar = getSupportActionBar();
    actionBar.hide();      //隐藏标题栏
    }

    @Override
    public void onWindowFocusChanged(boolean hasFocus) {
        super.onWindowFocusChanged(hasFocus);
        if (hasFocus && Build.VERSION.SDK_INT >= 19) {
            View decorview = getWindow().getDecorView();
            decorview.setSystemUiVisibility(
                    View.SYSTEM_UI_FLAG_LAYOUT_STABLE
                    |View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
                    | View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
                    | View.SYSTEM_UI_FLAG_FULLSCREEN
                    | View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY);
        }
    }
}

xml布局

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.zjc.immersivetest.MainActivity">

    <ImageView
        android:id="@+id/image_view"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:src="@drawable/stone"
        android:scaleType="centerCrop"/>

</RelativeLayout>

效果