Toolbar not showing in API Level 19 in Android

Question

I read this and I tried to reorder the views but the toolbar is still not visible on Android 19.

I don't know why the toolbar is not visible on android 19.

This is the repo.

<RelativeLayout
    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.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            android:background="?attr/colorPrimary"
            android:elevation="4dp"
            android:theme="@style/ThemeOverlay.AppCompat.ActionBar"
            app:popupTheme="@style/ThemeOverlay.AppCompat.Light">

            <ImageButton
                android:id="@+id/bt_picture"
                android:layout_width="36dp"
                android:layout_height="36dp"
                android:background="@drawable/ic_photo_white_24dp"
                android:layout_gravity="end"
                android:layout_marginEnd="10dp"/>

            <ImageButton
                android:id="@+id/bt_pdf"
                android:layout_width="36dp"
                android:layout_height="36dp"
                android:background="@drawable/ic_picture_as_pdf_white_24dp"
                android:layout_gravity="end"
                android:layout_marginEnd="10dp"/>

            <ImageButton
                android:id="@+id/bt_clear"
                android:layout_width="36dp"
                android:layout_height="36dp"
                android:background="@drawable/ic_delete_white_36dp"
                android:layout_gravity="end"
                android:layout_marginEnd="10dp"/>

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

    <com.example.ricardochampa.signatureapp.SignatureView
        android:id="@+id/signature_view"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

    <View
        android:id="@+id/line_view"
        android:layout_width="wrap_content"
        android:layout_height="5dp"
        android:layout_alignParentBottom="true"
        android:layout_centerHorizontal="true"
        android:layout_marginBottom="60dp"
        android:layout_marginStart="70dp"
        android:background="@color/grey"/>

    <TextView
        android:id="@+id/textView2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignTop="@+id/line_view"
        android:layout_centerHorizontal="true"
        android:textColor="@color/grey"
        android:layout_marginTop="10dp"
        android:text="@string/sign_here" />

</RelativeLayout>

Answer 1

Try the layout below.

  <RelativeLayout
    android:layout_width="match_parent"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_height="match_parent">
    <android.support.design.widget.AppBarLayout
        android:id="@+id/appBar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

        <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="50dp"
            android:background="@color/colorPrimary"
            android:elevation="4dp"
            android:theme="@style/ThemeOverlay.AppCompat.ActionBar"
            app:popupTheme="@style/ThemeOverlay.AppCompat.Light">

            <ImageButton
                android:id="@+id/bt_picture"
                android:layout_width="36dp"
                android:layout_height="36dp"
                android:layout_gravity="end"
                android:layout_marginEnd="10dp"
                android:background="@drawable/ic_photo_white_24dp" />

            <ImageButton
                android:id="@+id/bt_pdf"
                android:layout_width="36dp"
                android:layout_height="36dp"
                android:layout_gravity="end"
                android:layout_marginEnd="10dp"
                android:background="@drawable/ic_picture_as_pdf_white_24dp" />

            <ImageButton
                android:id="@+id/bt_clear"
                android:layout_width="36dp"
                android:layout_height="36dp"
                android:layout_gravity="end"
                android:layout_marginEnd="10dp"
                android:background="@drawable/ic_delete_white_36dp" />

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

    <com.example.ricardochampa.signatureapp.SignatureView
        android:id="@+id/signature_view"
        android:layout_below="@+id/appBar"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

    <View
        android:id="@+id/line_view"
        android:layout_width="wrap_content"
        android:layout_height="5dp"
        android:layout_alignParentBottom="true"
        android:layout_centerHorizontal="true"
        android:layout_marginBottom="60dp"
        android:layout_marginStart="70dp"
        android:background="@color/grey"/>

    <TextView
        android:id="@+id/textView2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignTop="@+id/line_view"
        android:layout_centerHorizontal="true"
        android:textColor="@color/grey"
        android:layout_marginTop="10dp"
        android:text="@string/sign_here" />

</RelativeLayout>

And in activity add (optionally)

 Toolbar toolbar = findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);
    if(getSupportActionBar()!=null){
        getSupportActionBar().setDisplayHomeAsUpEnabled(false);
    }

The reason was ToolBar is getting hide by SignatureView . Although i donot have any idea right now how it is getting visible above 19.