Develop Reference

RelativeLayout doesn't fill the screen horizontally

I have the following layout:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/fragment_container"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:id="#+id/app_name"
android:text="#string/app_name"
android:layout_centerHorizontal="true"
android:textSize="30sp"
android:textColor="#FF000000"
android:singleLine="true"
android:layout_marginTop="10dp"
android:layout_marginLeft="30dp"
android:layout_marginRight="30dp"
android:layout_alignParentTop="true"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
/>
</RelativeLayout>
I expected the layout to extend to the edges of the screen, but instead here's what I get:
The declared theme is Theme.K9Dialog:
<resources>
<style name="Theme.K9Dialog" parent="Theme.AppCompat.NoActionBar">
<item name="android:windowFrame">#null</item>
<item name="android:windowBackground">#drawable/popup_background</item>
<item name="android:windowIsFloating">true</item>
<item name="android:windowAnimationStyle">#android:style/Animation.Dialog</item>
<item name="android:windowContentOverlay">#drawable/panel_separator</item>
</style>
Am I misunderstanding what android:layout_width is supposed to do?

This is happening because of <item name="android:windowIsFloating">true</item> in your app theme, should work fine after removing that. Also I am not why you need all those attributes like android:windowFrame and ndroid:windowAnimationStyle in your app theme. If there is no such requirement try using default app theme and add only those attributes to theme which you want to change .

Activty height does not match parent on Xiaomi Redmi Note 9 Pro

I am trying to create an activity that will match the parent height. When I am testing the application on Pixel XL the application is fine, but when install on Xiaomi Redmi Note 9 Pro I have one part of the screen that it's not covered. This is the part above the camera, and it might be that my question is not only for this phone but I guess for all the others with the same design.
This is how it looks on pixel and it's ok:
And this is how it looks on Xiaomi Redmi Note 9 Pro:
This is my activity code:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#color/main_screen_background"
tools:context=".activty.WelcomeActivity">
<include layout="#layout/toolbar" />
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/main_menu_recycler_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_below="#+id/toolbar"
android:layout_marginTop="20dp"
android:layout_marginBottom="60dp" />
</RelativeLayout>
And this is my Toolbar if needed:
<androidx.appcompat.widget.Toolbar
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#color/main_screen_background"
android:theme="#style/AppFullScreenTheme"
app:popupTheme="#style/ThemeOverlay.AppCompat.Light">
<RelativeLayout
android:id="#+id/test_menu_language_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginStart="30dp"
android:layout_marginTop="30dp"
android:layout_marginEnd="30dp">
<ImageView
android:id="#+id/about_dropdown_menu"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/ic_ikonki_potrosuvaci_02" />
<TextView
android:id="#+id/language_dropdown_menu"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentEnd="true"
android:text="MK"
android:textColor="#color/white"
android:textSize="20dp" />
</RelativeLayout>
</androidx.appcompat.widget.Toolbar>
What I want to achieve is to have covered also that black part and have the color from the activity, probably an easy thing but I am little rusty with android. I checked the other applications and they are covering that part.

So actually there are only two lines of code needed to be added in your v27/styles.xml:
<item name="android:windowLayoutInDisplayCutoutMode">
shortEdges <!-- default, shortEdges, never -->
</item>
<item name="android:windowTranslucentStatus">true</item>
The first will cover that area and the second will set the color of the activity to that area. This is how my styles.xml looks like:
<?xml version="1.0" encoding="utf-8"?>
<resources>
<style name="AppFullScreenTheme" parent="Theme.AppCompat.Light.NoActionBar">
<item name="android:windowNoTitle">true</item>
<item name="android:windowActionBar">false</item>
<item name="android:windowFullscreen">true</item>
<item name="android:windowLayoutInDisplayCutoutMode">
shortEdges <!-- default, shortEdges, never -->
</item>
<item name="android:windowTranslucentStatus">true</item>
<item name="android:windowContentOverlay">#null</item>
<item name="android:popupMenuStyle">#style/PopupMenu</item>
<item name="android:textAppearanceLargePopupMenu">#style/myPopupMenuTextAppearanceLarge
</item>
<item name="android:textAppearanceSmallPopupMenu">#style/myPopupMenuTextAppearanceSmall
</item>
</style>
</resources>
Finally I have applied this style to every activity that I have.

Android | Add line on the navbar

In my v27\style.xml I have the following code to set a white navbar:
<style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">
<item name="colorPrimary">#color/colorPrimary</item>
<item name="colorPrimaryDark">#color/colorPrimaryDark</item>
<item name="colorAccent">#color/colorAccent</item>
<item name="android:navigationBarColor">#android:color/white</item>
<item name="android:windowLightNavigationBar">true</item>
</style>
It works, but the white navbar "joins" with the white background. I would to add an horizontal line on the navbar, in each activity. How can I do?
This is what I would (from Youtube), I highlighted it with red rectangle:

I think for cases like these you may need to have a custom toolbar layout so that you can optimise the layout whichever way you like.
Something like this:
<?xml version="1.0" encoding="utf-8"?>
<androidx.appcompat.widget.Toolbar
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary"
app:popupTheme="#style/ThemeOverlay.AppCompat.Light"
app:theme="#style/ThemeOverlay.AppCompat.Dark.ActionBar">
<LinearLayout
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<TextView
android:id="#+id/tvToolBarTitle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:textSize="18sp"
android:text="Toobar"
android:fontFamily="#font/filson_pro_book"
android:textColor="#color/white"
android:visibility="visible"/>
<FrameLayout
android:layout_gravity="center_horizontal"
android:background="#color/white"
android:layout_width="100dp"
android:layout_height="1dp"/>
</LinearLayout>

You would probably want to add an horizontal line each time you open the nav drawer:
<View
android:layout_width="fill_parent"
android:layout_height="1dp"
android:background="#FF0000FF"
android:layout_gravity = "bottom/>
If you want the line to be on half of the screen (only on the nav)- add it inside the nav.
If you want the line to be on the whole screen (as you marked in the picture)- add it after adding the nav.

Since API 27 there is an attribute in the style called navigationBarDividerColor that allows to do that. You can complement it with the navigationBarColor to make it look like the one in your screenshot.
<?xml version="1.0" encoding="utf-8"?>
<resources>
<style name="AppTheme" parent="Theme.AppCompat.Light">
...
<item name="android:navigationBarColor">#android:color/white</item>
<item name="android:navigationBarDividerColor">#DBDBDB</item>
</style>
</resources>

Android change color of home arrow in android.support.v7.widget.Toolbar

I am trying to change color of home arrow indicator in custom toolbar.
There is list of examples that I found but nothing worked for me.
Here is my layout
<android.support.v7.widget.Toolbar
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/title_bar_toolbar_id"
app:theme="#style/ToolbarColoredBackArrow"
app:popupTheme="#style/AppTheme"
android:layout_height="?attr/actionBarSize"
android:layout_width="match_parent"
android:fitsSystemWindows="true"
android:minHeight="?attr/actionBarSize"
android:colorControlNormal="#color/hamburger_color"
android:background="#color/custom_theme_color" >
<LinearLayout
android:id="#+id/base_title_bar_toolbar_id_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal">
<ImageView
android:id="#+id/activity_calendar_toolbar_change_view_type"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/select_semester_view"
android:layout_gravity="center_vertical"
android:padding="10dp" />
<TextView
android:gravity="center"
android:layout_gravity="center"
android:id="#+id/base_title_bar_toolbar_header"
android:layout_weight="0.1"
style="#style/CustomToolBarTitleStyleBase"
android:text="#string/calendar" />
<ImageView
android:padding="13dp"
android:id="#+id/activity_calendar_toolbar_save_date_to_calendar"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/save_date_to_calendar"
android:layout_gravity="center_vertical|start" />
<ImageView
android:id="#+id/activity_calendar_toolbar_select_semester_to_show"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/select_semester_to_show"
android:layout_gravity="center_vertical|start"
android:padding="13dp" />
</LinearLayout>
</android.support.v7.widget.Toolbar>
The styles are:
<style name="ToolbarColoredBackArrow" parent="AppTheme">
<item name="android:textColorSecondary">#color/hamburger_color</item>
<item name="android:textColorPrimary">#color/hamburger_color</item>
<item name="colorControlNormal">#color/hamburger_color</item>
</style>
<style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">
<item name="android:actionBarStyle">#style/MyActionBar</item>
<item name="android:actionBarTabTextStyle">#style/MyActionBarTabText</item>
<!-- Support library compatibility -->
<item name="actionBarStyle">#style/MyActionBar</item>
<item name="actionBarTabTextStyle">#style/MyActionBarTabText</item>
</style>
<style name="MyActionBar" parent="#style/Widget.AppCompat.Light.ActionBar.Solid.Inverse">
<item name="android:background">#color/custom_theme_color</item>
<item name="android:titleTextStyle">#style/MyActionBar.TitleTextStyle</item>
<!-- Support library com`enter code here`patibility -->
<item name="background">#color/custom_theme_color</item>
<item name="titleTextStyle">#style/MyActionBar.TitleTextStyle</item>
</style>
I tried all possibilities that I found in examples,
but nothing worked for me.

Haha, this is one of the most frustrating styling issues in Android right now...
Try creating a style like this
<style name="AppThemeNoActionBar" parent="Theme.AppCompat.Light.NoActionBar">
<item name="android:textColorSecondary">#000000</item>
</style>
and using it in your Activity (you will probably want to merge it with your current style, as it is just the parent and this one param that matters) and of course replace the #000000 with some other color.

First of all you don't need a separate ImageView for your arrow navigation button. Just use the one from support design resources which will resize automatically according to the screen size.
Drawable upArrow = getResources().getDrawable(android.support.v7.appcompat.R.drawable.abc_ic_ab_back_mtrl_am_alpha);
upArrow.setColorFilter(Color.parseColor("#ffffff"), PorterDuff.Mode.SRC_ATOP);
toolbar.setNavigationIcon(upArrow);

How to bring ImageView under the transparent Status Bar

In the images below,I am trying to bring the ImageView under the StatusBar. But its not happening.
Image Screenshot on Android API 19
Image Screenshot on Android API 22
I went on Android transparent status bar and actionbar (this question) and tried to implement the same but its not working.
The xml layout of the activity is
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout
android:layout_height="match_parent"
android:layout_width="match_parent"
android:fitsSystemWindows="true"
xmlns:android="http://schemas.android.com/apk/res/android">
<LinearLayout
android:id="#+id/category_layout_top"
android:fitsSystemWindows="true"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<FrameLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<ImageView
android:fitsSystemWindows="true"
android:layout_width="390dp"
android:layout_height="390dp"
android:id="#+id/category_Image_View"/>
<android.support.v7.widget.Toolbar
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/def_toolbar"
android:layout_height="wrap_content"
android:layout_width="match_parent"
android:minHeight="?attr/actionBarSize"
android:background="#00FFFFFF"
android:layout_alignParentTop="true" />
</FrameLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="50dp"
android:id="#+id/category_linearlayout">
<TextView android:layout_width="match_parent"
android:layout_height="match_parent"
android:singleLine="true"
android:id="#+id/category_textView"
/>
</LinearLayout>
</LinearLayout>
</FrameLayout>
I tried the below code in the onCreate() method also
setStatusBarTranslucent(true);
protected void setStatusBarTranslucent(boolean makeTranslucent) {
if (makeTranslucent) {
getWindow().addFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS);
} else {
getWindow().clearFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS);
}
}
style.xml
<style name="AppTheme" parent="Theme.AppCompat.Light.NoActionBar">
<!-- Customize your theme here. -->
<item name="colorPrimary">#color/colorPrimary</item>
<item name="colorPrimaryDark">#color/colorPrimaryDark</item>
<item name="colorAccent">#color/colorAccent</item>
</style>
style-v21.xml
<style name="AppTheme.NoActionBar">
<item name="windowActionBar">false</item>
<item name="windowNoTitle">true</item>
<item name="android:windowDrawsSystemBarBackgrounds">true</item>
<item name="android:statusBarColor">#android:color/transparent</item>
</style>
AppTheme is the style used in the activity.
EDIT 1
I used a color in the background of FrameLayout to check whether it was under the status bar or not. And it is not.
So the problem is not with Layout, I guess.
EDIT 2
this is the desired result

In style-v21 you are overriding the style AppTheme.NoActionBar, but you said the style you use in your activity is the AppTheme style.
You need to override the AppTheme layout in style-v21 or define AppTheme.NoActionBar in you activity.