在你的XML中使用这段代码，你将能够在你的活动中看到时间条:

<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true">

在状态栏下绘制布局:

值/ styles.xml

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

values-v21 / styles.xml

<item name="android:windowDrawsSystemBarBackgrounds">true</item>
<item name="android:statusBarColor">@color/colorPrimaryDark</item>

使用已经照顾fitsSystemWindows参数的CoordinatorLayout/DrawerLayout，或者创建自己的布局，如下所示:

public class FitsSystemWindowConstraintLayout extends ConstraintLayout {

    private Drawable mStatusBarBackground;
    private boolean mDrawStatusBarBackground;

    private WindowInsetsCompat mLastInsets;

    private Map<View, int[]> childsMargins = new HashMap<>();

    public FitsSystemWindowConstraintLayout(Context context) {
        this(context, null);
    }

    public FitsSystemWindowConstraintLayout(Context context, AttributeSet attrs) {
        this(context, attrs, 0);
    }

    public FitsSystemWindowConstraintLayout(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);

        if (ViewCompat.getFitsSystemWindows(this)) {
            ViewCompat.setOnApplyWindowInsetsListener(this, new android.support.v4.view.OnApplyWindowInsetsListener() {
                @Override
                public WindowInsetsCompat onApplyWindowInsets(View view, WindowInsetsCompat insets) {
                    FitsSystemWindowConstraintLayout layout = (FitsSystemWindowConstraintLayout) view;
                    layout.setChildInsets(insets, insets.getSystemWindowInsetTop() > 0);
                    return insets.consumeSystemWindowInsets();
                }
            });
            setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_STABLE
                    | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN);
            TypedArray typedArray = context.obtainStyledAttributes(new int[]{android.R.attr.colorPrimaryDark});
            try {
                mStatusBarBackground = typedArray.getDrawable(0);
            } finally {
                typedArray.recycle();
            }
        } else {
            mStatusBarBackground = null;
        }
    }

    public void setChildInsets(WindowInsetsCompat insets, boolean draw) {
        mLastInsets = insets;
        mDrawStatusBarBackground = draw;
        setWillNotDraw(!draw && getBackground() == null);

        for (int i = 0; i < getChildCount(); i++) {
            View child = getChildAt(i);
            if (child.getVisibility() != GONE) {
                if (ViewCompat.getFitsSystemWindows(this)) {
                    ConstraintLayout.LayoutParams layoutParams = (ConstraintLayout.LayoutParams) child.getLayoutParams();

                    if (ViewCompat.getFitsSystemWindows(child)) {
                        ViewCompat.dispatchApplyWindowInsets(child, insets);
                    } else {
                        int[] childMargins = childsMargins.get(child);
                        if (childMargins == null) {
                            childMargins = new int[]{layoutParams.leftMargin, layoutParams.topMargin, layoutParams.rightMargin, layoutParams.bottomMargin};
                            childsMargins.put(child, childMargins);
                        }
                        if (layoutParams.leftToLeft == LayoutParams.PARENT_ID) {
                            layoutParams.leftMargin = childMargins[0] + insets.getSystemWindowInsetLeft();
                        }
                        if (layoutParams.topToTop == LayoutParams.PARENT_ID) {
                            layoutParams.topMargin = childMargins[1] + insets.getSystemWindowInsetTop();
                        }
                        if (layoutParams.rightToRight == LayoutParams.PARENT_ID) {
                            layoutParams.rightMargin = childMargins[2] + insets.getSystemWindowInsetRight();
                        }
                        if (layoutParams.bottomToBottom == LayoutParams.PARENT_ID) {
                            layoutParams.bottomMargin = childMargins[3] + insets.getSystemWindowInsetBottom();
                        }
                    }
                }
            }
        }

        requestLayout();
    }

    public void setStatusBarBackground(Drawable bg) {
        mStatusBarBackground = bg;
        invalidate();
    }

    public Drawable getStatusBarBackgroundDrawable() {
        return mStatusBarBackground;
    }

    public void setStatusBarBackground(int resId) {
        mStatusBarBackground = resId != 0 ? ContextCompat.getDrawable(getContext(), resId) : null;
        invalidate();
    }

    public void setStatusBarBackgroundColor(@ColorInt int color) {
        mStatusBarBackground = new ColorDrawable(color);
        invalidate();
    }

    @Override
    public void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        if (mDrawStatusBarBackground && mStatusBarBackground != null) {
            int inset = mLastInsets != null ? mLastInsets.getSystemWindowInsetTop() : 0;
            if (inset > 0) {
                mStatusBarBackground.setBounds(0, 0, getWidth(), inset);
                mStatusBarBackground.draw(canvas);
            }
        }
    }
}

main_activity.xml

<FitsSystemWindowConstraintLayout 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"
    android:fitsSystemWindows="true">

    <ImageView
        android:layout_width="0dp"
        android:layout_height="0dp"
        android:fitsSystemWindows="true"
        android:scaleType="centerCrop"
        android:src="@drawable/toolbar_background"
        app:layout_constraintBottom_toBottomOf="@id/toolbar"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <android.support.v7.widget.Toolbar
        android:id="@+id/toolbar"
        android:layout_width="0dp"
        android:layout_height="?attr/actionBarSize"
        android:background="@android:color/transparent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <LinearLayout
        android:layout_width="0dp"
        android:layout_height="0dp"
        android:gravity="center"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toBottomOf="@id/toolbar">

        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:gravity="center"
            android:text="Content"
            android:textSize="48sp" />
    </LinearLayout>
</FitsSystemWindowConstraintLayout>

结果:

截图:

下面的代码将使你的状态栏和导航栏透明(注意，这将使你的布局成为像游戏中使用的布局一样的全屏布局):

@Override
public void onWindowFocusChanged(boolean hasFocus) {
    super.onWindowFocusChanged(hasFocus);
    if (hasFocus) {
        hideSystemUI();
    }
}

private void hideSystemUI() {
    // Enables sticky immersive mode.
    // For "lean back" mode, remove SYSTEM_UI_FLAG_IMMERSIVE_STICKY.
    // Or for regular immersive mode replace it with SYSTEM_UI_FLAG_IMMERSIVE
    View decorView = getWindow().getDecorView();
    decorView.setSystemUiVisibility(
            View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY
                    // Set the content to appear under the system bars so that the
                    // content doesn't resize when the system bars hide and show.
                    | View.SYSTEM_UI_FLAG_LAYOUT_STABLE
                    | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
                    | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
                    // Hide the nav bar and status bar
                    | View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
                    | View.SYSTEM_UI_FLAG_FULLSCREEN);
}

要了解更多，请访问这个链接。

你只需要进入mainactivity。java

protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        Window g = getWindow();
        g.setFlags(WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS, WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS);

        setContentView(R.layout.activity_main);

    }

你所需要做的就是在你的主题中设置这些属性:

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

你的活动/容器布局，你希望有一个透明的状态栏需要这个属性集:

android:fitsSystemWindows="true"

这通常是不可能执行这肯定在预kitkat，看起来你可以这样做，但一些奇怪的代码使它如此。

编辑:我推荐这个lib: https://github.com/jgilfelt/SystemBarTint为许多前棒棒糖状态栏颜色控制。

经过深思熟虑，我了解到完全禁用状态栏和棒棒糖导航栏上的半透明或任何颜色的答案是在窗口上设置这个标志:

// 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);
}

没有其他主题是必要的，它产生如下内容:

您可以使用下面的代码。

getWindow().getDecorView().setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN); 
getWindow().setStatusBarColor(Color.TRANSPARENT);

将此布局包含在主布局中。

toolbar.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.appcompat.widget.Toolbar xmlns:android="http://schemas.android.com/apk/res/android"
        android:id="@+id/toolbarNav"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="@android:color/transparent"
        app:contentInsetEnd="0dp"
        app:contentInsetLeft="0dp"
        app:contentInsetRight="0dp"
        app:contentInsetStart="0dp">

        <RelativeLayout
            android:id="@+id/rlBackImageLayout"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:background="@drawable/main_background2">  //add your color here

            <LinearLayout
                android:layout_width="match_parent"
                android:layout_height="@dimen/_40sdp"
                android:layout_marginTop="@dimen/_16sdp"
                android:orientation="horizontal">

                <ImageView
                    android:id="@+id/toolbarIcon"
                    android:layout_width="@dimen/_30sdp"
                    android:layout_height="@dimen/_30sdp"
                    android:layout_gravity="center"
                    android:layout_marginStart="@dimen/_10sdp"
                    android:padding="@dimen/_5sdp"
                    android:src="@drawable/nav_icon" />

                <TextView
                    android:id="@+id/txtTitle"
                    android:layout_width="match_parent"
                    android:layout_height="match_parent"
                    android:layout_gravity="center"
                    android:layout_marginEnd="@dimen/_30sdp"
                    android:fontFamily="@font/muli_semibold"
                    android:gravity="center"
                    android:textColor="#fff"
                    android:textSize="@dimen/_14ssp"
                    android:textStyle="bold"
                    tools:text="test Data" />

            </LinearLayout>

        </RelativeLayout>

    </androidx.appcompat.widget.Toolbar>

注:可以用dp代替SDP，用sp代替SSP。