CollapsingToolbarLayout ne peut pas être converti en android.support.v7.widget.Toolbar

Question

En travaillant sur cette disposition de la barre d'outils Collapse, tout fonctionne correctement, mais au moment où j'ajoute du code dans l'activité principale de la classe java, une erreur apparaît et l'application plante. Sans code Java, cela fonctionnait correctement.

XML:

 <?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" 
    xmlns:tools="http://schemas.android.com/tools" 
    android:layout_width="match_parent" 
    android:layout_height="match_parent" 
    tools:context="app.com.alphaapps.android.cordinator.MainActivity"> 

    <android.support.design.widget.AppBarLayout 
     android:id="@+id/app_bar_layout" 
     android:layout_width="match_parent" 
     android:layout_height="wrap_content" 
     android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar" 
     android:fitsSystemWindows="true" 
      > 

     <android.support.design.widget.CollapsingToolbarLayout 
      android:id="@+id/toolbar" 
      android:layout_width="match_parent" 
      android:layout_height="350dp" 
      app:layout_scrollFlags="scroll|exitUntilCollapsed" 
      app:contentScrim="?attr/colorPrimary" 
      app:expandedTitleTextAppearance="@android:color/transparent" 
      android:fitsSystemWindows="true" 
      > 

      <ImageView 
       android:layout_width="match_parent" 
       android:layout_height="350dp" 
       app:layout_collapseMode="parallax" 
       android:src="@drawable/firework" 
       android:contentDescription="@string/app_name" 
       android:scaleType="centerCrop" 

       /> 

      <android.support.v7.widget.Toolbar 
       android:layout_width="match_parent" 
       android:layout_height="?attr/actionBarSize" 
       android:popupTheme="@style/ThemeOverlay.AppCompat.Light" 
       android:title="@string/recent_news" 
       app:layout_collapseMode="pin" /> 


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

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

    <android.support.v4.widget.NestedScrollView 
     android:layout_width="match_parent" 
     android:layout_height="match_parent" 
     android:clipToPadding="false" 
     app:layout_behavior="@string/appbar_scrolling_view_behavior" 

     > 

     <android.support.v7.widget.CardView 
      android:layout_width="match_parent" 
      android:layout_height="wrap_content" 
      android:layout_marginBottom="16dp" 
      app:cardElevation="5dp" 
      app:cardUseCompatPadding="true" 
      > 



      <LinearLayout 
       android:layout_width="match_parent" 
       android:layout_height="wrap_content" 
       android:orientation="vertical"> 

       <TextView 
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content" 
        android:padding="12dp" 
        android:textSize="20sp" 
        android:layout_marginTop="12dp" 
        android:textStyle="bold" 
        android:textColor="@color/colorPrimary" 
        android:text="@string/recent_news" 
        /> 

       <LinearLayout 
        android:layout_width="match_parent" 
        android:layout_height="wrap_content" 
        android:orientation="horizontal" 
        android:padding="12dp" 
        > 

        <ImageView 
         android:contentDescription="@string/app_name" 
         android:src="@drawable/ic_clock" 
         android:layout_weight="1" 
         android:layout_width="0dp" 
         android:layout_height="wrap_content" /> 

        <TextView 
         android:layout_gravity="center_vertical" 
         android:layout_width="0dp" 
         android:layout_weight="9" 
         android:layout_height="wrap_content" 
         android:padding="12dp" 
         android:textSize="14sp" 
         android:layout_marginTop="12dp" 
         android:textStyle="bold" 
         android:textColor="@color/colorPrimary" 
         android:text="@string/publish_date" 
         /> 


       </LinearLayout> 


       <TextView 
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content" 
        android:padding="12dp" 
        android:textSize="13sp" 
        android:lineSpacingMultiplier="1.5" 
        android:layout_marginTop="12dp" 

        android:text="@string/in_news" 
        /> 



      </LinearLayout> 

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

    </android.support.v4.widget.NestedScrollView> 

    <android.support.design.widget.FloatingActionButton 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:src="@drawable/ic_fav" 
     android:elevation="6dp" 
     app:pressedTranslationZ="12dp" 
     app:layout_anchor="@id/app_bar_layout" 
     app:layout_anchorGravity="bottom|right|end" 

     /> 

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

MainActivity

import android.os.Bundle; 
import android.support.v7.app.AppCompatActivity; 
import android.support.v7.widget.Toolbar; 

public class MainActivity extends AppCompatActivity { 

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

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

LogCat

java.lang.RuntimeException: Unable to start activity 
ComponentInfo{app.com.alphaapps.android.cordinator/app.com.alphaapps.android. 
cordinator.MainActivity}: java.lang.ClassCastException: 
android.support.design.widget.CollapsingToolbarLayout cannot be cast to 
android.support.v7.widget.Toolbar 

                               Caused by: java.lang.ClassCastException: android.support.design.widget.CollapsingToolbarLayout cannot be cast to android.support.v7.widget.Toolbar 
                            at app.com.alphaapps.android.cordinator.MainActivity.onCreate(MainActivity.java:14) 

Answer 1

Retirer

android:id="@+id/toolbar" 

effondrement mise en page de la barre et le mettre dans la barre d'outils

Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar); 
<android.support.v7.widget.Toolbar 
      android:id="@+id/toolbar" 
      android:layout_width="match_parent" 
      android:layout_height="?attr/actionBarSize" 
      android:popupTheme="@style/ThemeOverlay.AppCompat.Light" 
      android:title="@string/recent_news" 
      app:layout_collapseMode="pin" />