How to set Navigation arrow in Collapsing Toolbar and set Onclicklistener

Question

I was implementing an collpasing toolbar for my Activity. I was wondering if it is possible to set and navigation arrow to the Collapsing toolbar layout and set Onclick listener which will take me to previous activity. I can sucessfully implement such feature using only toolbar layout which is given as

    <android.support.v7.widget.Toolbar
        android:id="@+id/toolbar_details"
        android:title="Disclaimer"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="#fff"
        android:minHeight="56dp"
        android:layout_alignParentTop="true"
        app:theme="@style/ThemeOverlay.AppCompat.Light"/>

and in OnCreate Method, I use

     Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar_details);
        setSupportActionBar(toolbar);
        tutorProfile.this.setTitle(getIntent().getStringExtra("My Dashboard"));
        toolbar.setNavigationIcon(R.drawable.ic_arrow_back_black_24dp);


        toolbar.setNavigationOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                Intent check = new Intent(CurrentActivity.this, PreviousActivity.class);
                startActivity(check);
                finish();

            }
        });

But in Collpasing toolbar layout how to achive same function. Here is the xml layout

<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/collapsing"
        android:layout_width="match_parent"
        android:layout_height="150dip"
        android:fitsSystemWindows="true"
        app:contentScrim="#784242"
        app:expandedTitleMarginBottom="20dp"
        app:expandedTitleMarginEnd="64dp"
        app:expandedTitleMarginStart="48dp"
        app:layout_scrollFlags="scroll|exitUntilCollapsed">

        <ImageView
            app:layout_collapseMode="parallax"
            android:src="@drawable/feedback_draw"
            android:contentDescription="@string/app_name"
            android:scaleType="centerCrop"
            android:layout_width="match_parent"
            android:layout_height="200dp" />

        <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="56dp"
            app:popupTheme="@style/ThemeOverlay.AppCompat.Light"
            app:layout_collapseMode="pin" />

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

I searched for couple of minutes but couldn't find any solution. Thanks for help in advance.

Answer 1

Why don't you simple use toolbar.setDisplayHomeAsUpEnabled(true) and then

override fun onOptionsItemSelected(item: MenuItem): Boolean {
    when (item.itemId) {
        android.R.id.home -> {
            finish()
            return true
        }
    }
    return super.onOptionsItemSelected(item)
}