Android Completely transparent Status Bar?

All you need to do is set these properties in your theme:

<item name="android:windowTranslucentStatus">true</item>
<item name="android:windowTranslucentNavigation">true</item>

Your activity / container layout you wish to have a transparent status bar needs this property set:

android:fitsSystemWindows="true"

It is generally not possible to perform this for sure on pre-kitkat, looks like you can do it but some strange code makes it so.

EDIT: I would recommend this lib: https://github.com/jgilfelt/SystemBarTint for lots of pre-lollipop status bar color control.

Well after much deliberation I've learned that the answer to totally disabling the translucency or any color placed on the status bar and navigation bar for lollipop is to set this flag on the window:

// In Activity's onCreate() for instance
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
    Window w = getWindow();
    w.setFlags(WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS, WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS);
}

No other theme-ing is necessary, it produces something like this:

Just add this line of code to your main java file:

getWindow().setFlags(
    WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS,
    WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS
);

You Can Use Below Code To Make Status Bar Transparent. See Images With red highlight which helps you to identify use of Below code

Kotlin code snippet for your android app

Step:1 Write down code in On create Method

if (Build.VERSION.SDK_INT >= 19 && Build.VERSION.SDK_INT < 21) {
    setWindowFlag(WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS, true)
}
if (Build.VERSION.SDK_INT >= 19) {
    window.decorView.systemUiVisibility = View.SYSTEM_UI_FLAG_LAYOUT_STABLE or View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
}
if (Build.VERSION.SDK_INT >= 21) {
    setWindowFlag(WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS, false)
    window.statusBarColor = Color.TRANSPARENT
}

Step2: You Need SetWindowFlag method which describe in Below code.

private fun setWindowFlag(bits: Int, on: Boolean) {
    val win = window
    val winParams = win.attributes
    if (on) {
        winParams.flags = winParams.flags or bits
    } else {
        winParams.flags = winParams.flags and bits.inv()
    }
    win.attributes = winParams
}

Java code snippet for your android app:

Step1: Main Activity Code

if (Build.VERSION.SDK_INT >= 19 && Build.VERSION.SDK_INT < 21) {
    setWindowFlag(this, WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS, true);
}
if (Build.VERSION.SDK_INT >= 19) {
    getWindow().getDecorView().setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_STABLE | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN);
}

if (Build.VERSION.SDK_INT >= 21) {
    setWindowFlag(this, WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS, false);
    getWindow().setStatusBarColor(Color.TRANSPARENT);
}

Step2: SetWindowFlag Method

public static void setWindowFlag(Activity activity, final int bits, boolean on) {
    Window win = activity.getWindow();
    WindowManager.LayoutParams winParams = win.getAttributes();
    if (on) {
        winParams.flags |= bits;
    } else {
        winParams.flags &= ~bits;
    }
    win.setAttributes(winParams);
}