1.设置沉浸式状态栏

public static void setStatusBarColor(Activity activity,int color){
       
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP){  // 5.0 以上
            activity.getWindow().setStatusBarColor(color); // 直接调用系统提供的方法 setStatusBarColor
        }
        // 4.4 - 5.0 之间  采用一个技巧，首先把他弄成全屏，在状态栏的部分加一个布局
        else if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT){
            // 首先把他弄成全屏（），在状态栏的部分加一个布局
            activity.getWindow().addFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS);

            // 在状态栏的部分加一个布局 setContentView 源码分析，自己加一个布局 (高度是状态栏的高度)
            View view = new View(activity);
            ViewGroup.LayoutParams params = new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT,getStatusBarHeight(activity));
            view.setLayoutParams(params);
            view.setBackgroundColor(color);
            
            ViewGroup decorView = (ViewGroup) activity.getWindow().getDecorView();
            decorView.addView(view);

            // 获取activity中setContentView布局的根布局
            ViewGroup contentView = (ViewGroup) activity.findViewById(android.R.id.content);
            contentView.setPadding(0,getStatusBarHeight(activity),0,0);
            
            // View activityView = contentView.getChildAt(0);
            // activityView.setPadding(0,getStatusBarHeight(activity),0,0);

            // activityView.setFitsSystemWindows(true);    
        }
    }

获取状态栏高度

// 获取状态栏的高度
private static int getStatusBarHeight(Activity activity) {
    Resources resources = activity.getResources();
    int statusBarHeightId = resources.getIdentifier("status_bar_height","dimen","android");
   return resources.getDimensionPixelOffset(statusBarHeightId);
}

2.设置Activity全屏

    public static void setActivityTranslucent(Activity activity){
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP){
            View decorView = activity.getWindow().getDecorView();
            decorView.setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN);
            activity.getWindow().setStatusBarColor(Color.TRANSPARENT);
        }
        else if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT){
            activity.getWindow().addFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS);
        }
    }

3.修改状态栏字体颜色（白底黑字）

3.1 Android6.0以上

      if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            Window window = activity.getWindow();
            window.addFlags(WindowManager.LayoutParams.FLAG_DRAWS_SYSTEM_BAR_BACKGROUNDS);
            window.setStatusBarColor(Color.WHITE);
            window.getDecorView().setSystemUiVisibility(View.SYSTEM_UI_FLAG_LIGHT_STATUS_BAR);
        }

3.2Android4.4-6.0之间

3.2.1适配MIUI(小米)

public static boolean setMiuiStatusBarDarkMode(Activity activity, boolean darkmode) {
        Class<? extends Window> clazz = activity.getWindow().getClass();
        try {
            int darkModeFlag = 0;
            Class<?> layoutParams = Class.forName("android.view.MiuiWindowManager$LayoutParams");
            Field field = layoutParams.getField("EXTRA_FLAG_STATUS_BAR_DARK_MODE");
            darkModeFlag = field.getInt(layoutParams);
            Method extraFlagField = clazz.getMethod("setExtraFlags", int.class, int.class);
            extraFlagField.invoke(activity.getWindow(), darkmode ? darkModeFlag : 0, darkModeFlag);
            return true;
        } catch (Exception e) {
            e.printStackTrace();
        }
        return false;
    }

3.2.2适配Flyme(魅族)

    public static boolean setMeizuStatusBarDarkIcon(Activity activity, boolean dark) {
        boolean result = false;
        if (activity != null) {
            try {
                WindowManager.LayoutParams lp = activity.getWindow().getAttributes();
                Field darkFlag = WindowManager.LayoutParams.class
                        .getDeclaredField("MEIZU_FLAG_DARK_STATUS_BAR_ICON");
                Field meizuFlags = WindowManager.LayoutParams.class
                        .getDeclaredField("meizuFlags");
                darkFlag.setAccessible(true);
                meizuFlags.setAccessible(true);
                int bit = darkFlag.getInt(null);
                int value = meizuFlags.getInt(lp);
                if (dark) {
                    value |= bit;
                } else {
                    value &= ~bit;
                }
                meizuFlags.setInt(lp, value);
                activity.getWindow().setAttributes(lp);
                result = true;
            } catch (Exception e) {
            }
        }
        return result;
    }

3.2.3其他

// 我们将状态栏设置为一个淡灰色，例：支付宝，今日头条等
setStatusBarColor(activity,Color.parseColor("#33000000"))

4. 状态栏颜色渐变过渡算法

    /**
     * 合成新的颜色值
     * @param fraction 颜色取值的级别 (0.0f ~ 1.0f)
     * @param startValue 开始显示的颜色
     * @param endValue 结束显示的颜色
     * @return 返回生成新的颜色值
     */
    public static int evaluate(float fraction, int startValue, int endValue) {
        int startA = (startValue >> 24) & 0xff;
        int startR = (startValue >> 16) & 0xff;
        int startG = (startValue >> 8) & 0xff;
        int startB = startValue & 0xff;

        int endA = (endValue >> 24) & 0xff;
        int endR = (endValue >> 16) & 0xff;
        int endG = (endValue >> 8) & 0xff;
        int endB = endValue & 0xff;

        return ((startA + (int) (fraction * (endA - startA))) << 24) |
                ((startR + (int) (fraction * (endR - startR))) << 16) |
                ((startG + (int) (fraction * (endG - startG))) << 8) |
                ((startB + (int) (fraction * (endB - startB))));
    }