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Status bar overlay image shifted down in android nought

I am trying to add an image to the status bar in xamarin forms android..
But the image is completely shifted down and coming under the normal status bar color i set in android nougat.
This happened when i updated the xamarin forms version to 2.4.0.74863
in 2.3.4.270 its working fine. Is this the xamrin forms issue or my code issue.
The code i used to draw overlay on status bar is
activity.Window.AddFlags(WindowManagerFlags.DrawsSystemBarBackgrounds);
activity.Window.ClearFlags(WindowManagerFlags.TranslucentStatus);
activity.Window.SetStatusBarColor(Android.Graphics.Color.Transparent);
ViewGroup contentView = (ViewGroup)activity.FindViewById(Android.Resource.Id.Content);
//if (contentView.ChildCount > 1)
//{
// contentView.RemoveViewAt(1);
//}
// get status bar height
int res = activity.Resources.GetIdentifier("status_bar_height", "dimen", "android");
int height = 0;
if (res != 0)
height = activity.Resources.GetDimensionPixelSize(res);
// create new imageview and set resource id
ImageView image = new ImageView(activity);
LinearLayout.LayoutParams params1 = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MatchParent, height);
params1.Width = LinearLayout.LayoutParams.MatchParent;
image.LayoutParameters = params1;
image.SetImageResource(imageRes);
image.SetScaleType(ImageView.ScaleType.FitXy);
// add image view to content view
contentView.AddView(image);
contentView.SetFitsSystemWindows(true);
I call this as a dependedncy from the xaml page.
EDIT
After i added the flags that #york mentioned the bottom navigation bar has become translucent and the app view went down.

Just need add the following code in your Activity style :
<style name="MyTheme.Base" parent="Theme.AppCompat.Light.DarkActionBar">
...
<item name="android:windowTranslucentStatus">false</item>
<item name="android:windowTranslucentNavigation">true</item>
<item name="android:statusBarColor">#android:color/transparent</item>
</style>
Effect :

How to control NavigationView margin between menu items

I have a navigation drawer with many items so the user needs to scroll up and down in order to see all the items.
I would like to reduce the margins between individual menu items, so that all items fit within a standard screen with no need to scroll.
Is there a way to control the margins in between the menu items?

Answer here helped me to reduce space at least between groups. I used the following dimen
<dimen tools:override="true" name="design_navigation_separator_vertical_padding">1dp</dimen>

We can create a drawable and set it as the NavigationView's itemBackground attribute. I will explain below:
If we walk through the NavigationMenuAdapter, we will see there are four types of items:
private static final int VIEW_TYPE_NORMAL = 0;
private static final int VIEW_TYPE_SUBHEADER = 1;
private static final int VIEW_TYPE_SEPARATOR = 2;
private static final int VIEW_TYPE_HEADER = 3;
What we want to work with is VIEW_TYPE_NORMAL. The attributes exposed to developers can be found in the below code:
case VIEW_TYPE_NORMAL:
{
NavigationMenuItemView itemView = (NavigationMenuItemView) holder.itemView;
itemView.setIconTintList(iconTintList);
if (textAppearanceSet) {
itemView.setTextAppearance(textAppearance);
}
if (textColor != null) {
itemView.setTextColor(textColor);
}
ViewCompat.setBackground(
itemView,
itemBackground != null ? itemBackground.getConstantState().newDrawable() : null);
NavigationMenuTextItem item = (NavigationMenuTextItem) items.get(position);
itemView.setNeedsEmptyIcon(item.needsEmptyIcon);
itemView.setHorizontalPadding(itemHorizontalPadding);
itemView.setIconPadding(itemIconPadding);
if (hasCustomItemIconSize) {
itemView.setIconSize(itemIconSize);
}
itemView.setMaxLines(itemMaxLines);
itemView.initialize(item.getMenuItem(), 0);
break;
}
Unfortunately,there is no interface for us to add margins between the NavigationMenuItemView. However, it allows us to set a background. So we can set a customer drawable to the NavigationView with a specific height. We only set a height in that drawable, like:
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"android:shape="rectangle">
<size android:height="60dp"/>
</shape>
Then apply this drawable to the NavigationView in the layout.xml, like:
<com.google.android.material.navigation.NavigationView
android:id="#+id/nav_view"
android:layout_width="wrap_content"
android:layout_height="match_parent"
app:itemBackground="#drawable/bk_menu_item"/>
I understand it is not a perfect solution, but it seems the only solution working in my case.

Paste this in styles.xml
<style name="NavigationTheme" parent="AppTheme">
<item name="android:textSize">16sp</item>
<item name="android:layout_marginBottom">02dp</item>
</style>
In navigation drawer put this in each item:
android:theme="#style/NavigationTheme"

add below code in dimens.xml
<dimen tools:override="true" name="design_navigation_icon_padding">16dp</dimen>

Changing ActionBar background affects Navigation drawer

I'm changing the ActionBar background in a fragment with a ScrollView. I have a ScrollView listener which changes the alpha of the items in the layered-list based on the scroll distance. The action bar actually works great. However, the Navigation Drawer background gets affected by this alpha change and I have no idea why; the nav drawer background becomes invisible. I can reproduce this easily on a Nexus 7 running Android L but it doesn't always happen for some 4.4 devices.
The main part is:
ActionBar actionBar = activity.getSupportActionBar();
LayerDrawable mActionBarBg = (LayerDrawable) getResources().getDrawable(R.drawable.background_actionbar);
if (mActionBarBg != null) {
setActionBarBgAlpha(0);
actionBar.setBackgroundDrawable(mActionBarBg);
}
Alpha calculator is this:
scrollView.setOnScrollChangedLitstener(new OnScrollChangedListener() {
#Override
public void onScrollChanged(int l, int t, int oldl, int oldt) {
t = Math.max(t, 0);
endpointHeader.setTranslationY(endpointHeader.getTop() + (t * 0.25f));
mScrollAlpha = (int) Math.min(alphaToHeightRatio * t, 255);
updateActionBarElemsAlpha(mScrollAlpha);
}
});
Couple of other methods:
private void updateActionBarElemsAlpha(int updatedAlpha){
if(mActionBarTitleColor != null){
mActionBarTitleColor.setAlpha(updatedAlpha);
mActionBarTitleView.setTextColor(mActionBarTitleColor.getColor());
}
setActionBarBgAlpha(updatedAlpha);
}
private void setActionBarBgAlpha(int alpha){
if(mActionBarBg != null){
mActionBarBg.getDrawable(1).setAlpha(alpha);
mActionBarBg.getDrawable(2).setAlpha(alpha);
}
}
background_actionbar.xml
<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android" >
<item android:drawable="#drawable/gradient" />
<item android:drawable="#color/grey_divider"/>
<item android:bottom="2dp"
android:drawable="#color/White"/>
</layer-list>

You should always mutate drawables before changing any attributes, otherwise you'll end up modifying the cached state which is by default shared across all instances.
if (mActionBarBg != null) {
mActionBarBg.mutate();
mActionBarBg.getDrawable(1).setAlpha(alpha);
mActionBarBg.getDrawable(2).setAlpha(alpha);
}

Get the current ActionBar size

I tried several things before and searched the web, but no answer.
How do I get the current ActionBar size?
I styled my ActionBar like this:
<style name="MusicSlide.Theme.ActionBar" parent="android:Widget.Holo.ActionBar">
<item name="android:height">60dp</item>
<item name="android:actionBarSize">60dp</item>
<item name="android:homeAsUpIndicator">#drawable/ic_drawer</item>
<item name="android:background">#color/complete_transparent</item>
<item name="android:titleTextStyle">#style/MusicSlide.Theme.ActionBar.TitleText</item>
<item name="android:subtitleTextStyle">#style/MusicSlide.Theme.ActionBar.TitleText</item>
</style>
It is transparent.
In my app I implemented a DrawerLayout. I don't want the DrawerLayout to be underneath the ActionBar , so I set the margin of the DrawerLayout:
final TypedArray styledAttributes = mContext.getTheme().obtainStyledAttributes(
new int[] { android.R.attr.actionBarSize });
int actionheight = (int) styledAttributes.getDimension(0, 0);
styledAttributes.recycle();
ViewGroup.MarginLayoutParams mlp = (ViewGroup.MarginLayoutParams) mDrawerListRight
.getLayoutParams();
mlp.setMargins(0,(actionheight + statbarheight),0,0);
The problem is that android.R.attr.actionBarSize returns the original height of the ActionBar.
How do I get the 60dp I set in my style?

android:actionBarSize isn't an attribute of Widget.ActionBar, this is why you aren't returning the correct value. Add that line to your app's theme, wherever you define android:actionBarStyle.

Android - Get highlight color of listview programatically (backward compatibly)

When the user presses a listview item it gets highlighted, and returns back to its original color when they let go.
I would like to programmatically query what colors these are.
On an Api version later than 14 it seems I can use
(i) Theme.resolveAttribute(int resid, TypedValue outValue, boolean resolveRefs) or
(ii) Theme.obtainStyledAttributes(int[] attrs)
//-- (i) ---------------------------------------------
int getAttrVal(int attr)
{
TypedValue Val = new TypedValue();
getContext().getTheme().resolveAttribute(attr, Val, true);
return Val.data;
}
int colBgd = getAttrVal(android.R.attr.colorBackground);
int colAh = getAttrVal(android.R.attr.colorActivatedHighlight);
int colPh = getAttrVal(android.R.attr.colorPressedHighlight); // not sure if this or prev is what im looking for!?
// (ii) ---------------------------------------------
TypedArray Arr = getContext().getTheme().obtainStyledAttributes(
new int[] {android.R.attr.colorPressedHighlight});
int colPh2 = arrTst.getColor(0, 0xFF00FF);
//--------------------------------------------------
On older Api versions this wont work since
android.R.attr.colorActivatedHighlight/colorPressedHighlight
were not available yet.
(1) Is there a to programmatically get these colours on api 8?
(2) I'm a bit confused as to some of the other functions in Theme
eg (iii) Theme.obtainStyledAttributes(int resid, int[] attrs)
// ---------------------------------------------
TypedArray Arr2 = getContext().getTheme().obtainStyledAttributes(
android.R.attr.colorBackground, new int[] {android.R.attr.colorPressedHighlight});
int colTst2 = arrTst.getColor(0, 0xFF00FF);
Here it seems not to matter what value I use for resid. What's the point of this parameter?
(3) What's the difference between R.attr and R.styleable?
Is R.attr supposed to be a replacement for R.styleable (and basically have corresponding entries), or do their purposes only partly overlap.

You should have a selector declared with the items bellow:
<item android:drawable="#color/selected" android:state_focused="true" android:state_pressed="true"/>
<item android:drawable="#color/selected" android:state_focused="false" android:state_pressed="true"/>
<item android:drawable="#color/selected" android:state_focused="true"/>
<item android:drawable="#color/normal" android:state_focused="false" android:state_pressed="false"/>
and set it as background for listRow