Android Material Design Mistake

Question

Hi, I want to create a material design using this tutorial. https://www.youtube.com/watch?v=pMO8EVkhJO8&list=PLonJJ3BVjZW6CtAMbJz1XD8ELUs1KXaTD&index=3

and in my design the app bar is indented on all sides. can someone help me uninstall this add-on and make the app look like a real app bar.

Here is my screen

app_bar

    <?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.Toolbar xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent" android:layout_height="wrap_content"
    android:background="#DDDD">

</android.support.v7.widget.Toolbar>

Primary activity

<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:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:paddingBottom="@dimen/activity_vertical_margin" tools:context=".MainActivity">

    <include android:id="@+id/app_bar" layout="@layout/app_bar"/>

    <TextView
        android:layout_below="@+id/app_bar"
        android:text="@string/hello_world" android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

</RelativeLayout>

maniActivity.java

private Toolbar toolbar;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    toolbar = (Toolbar) findViewById(R.id.app_bar);
    setSupportActionBar(toolbar);
}

Answer 1

In your Relative Layout you put Paddings. You need to delete them.

<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"  
 tools:context=".MainActivity">


    <include android:id="@+id/app_bar" layout="@layout/app_bar"/>

    <TextView
        android:layout_below="@+id/app_bar"
        android:text="@string/hello_world"  
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

</RelativeLayout>

. Padding. , LinearLayout orientation of vertical toolbar, relativelayout.

Answer 2

RelativeLayout

    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:paddingBottom="@dimen/activity_vertical_margin"

<?xml version="1.0" encoding="utf-8"?> 
<android.support.design.widget.CoordinatorLayout
     xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
        android:id="@+id/coordinator"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <android.support.design.widget.AppBarLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:theme="@style/ThemeOverlay.AppCompat.Dark">

            <include layout="@layout/toolbar"></include>

            <android.support.design.widget.TabLayout
                android:id="@+id/tablayout"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="?attr/colorPrimary"
                app:tabGravity="fill"/>

        </android.support.design.widget.AppBarLayout>

        <android.support.v4.view.ViewPager
            android:id="@+id/pager"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            app:layout_behavior="@string/appbar_scrolling_view_behavior"/>
</android.support.design.widget.CoordinatorLayout>