Parallax Scrolling/Collapsable Toolbar in Android

问题

So here is some code from a udacity project for Material Design. It is supposed to show a collapsing toolbar that transforms from a photo with text to simple text. The udacity videos lead me to believe the code worked but when I downloaded the app to my phone, the toolbar did not collapse (the OS is android 6.0.1, v23). Is there something I could change to ensure the toolbar collapses?

The code

xml

<android.support.design.widget.AppBarLayout
    android:id="@+id/app_bar_layout"
    android:layout_width="match_parent"
    android:layout_height="192dp"
    android:background="?colorPrimary">

    <android.support.design.widget.CollapsingToolbarLayout
        android:id="@+id/collapsing_toolbar_layout"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:collapsedTitleTextAppearance="@style/TextAppearance.AppCompat.Widget.ActionBar.Title.Inverse"
        app:expandedTitleTextAppearance="@style/TextAppearance.AppCompat.Widget.ActionBar.Title.Inverse"
        app:expandedTitleMarginStart="72dp"
        app:contentScrim="?attr/colorPrimary"
        app:layout_scrollFlags="scroll|exitUntilCollapsed">

            <ImageView
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                app:layout_collapseMode="parallax"
                android:scaleType="centerCrop"
                android:src="@drawable/eclairs" />


        <android.support.v7.widget.Toolbar
            android:id="@+id/app_bar"
            android:layout_width="match_parent"
            android:layout_height="?actionBarSize"
            android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"
            app:navigationIcon="@drawable/arrow_left"
            app:contentInsetStart="72dp"
            app:layout_collapseMode="pin" />


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

<ScrollView
    android:layout_width="match_parent"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    android:layout_height="wrap_content">
    <TextView
        android:layout_marginTop="16dp"
        android:textAppearance="@style/Base.TextAppearance.AppCompat.Body1"
        android:text="@string/cupcake_ipsum"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="16dp"
        android:layout_marginRight="16dp" />

</ScrollView>

JAVA

package com.example.android.dynamicsurfacesdemo;

import android.app.Activity;
import android.os.Bundle;
import android.support.design.widget.CollapsingToolbarLayout;

public class MainActivity extends Activity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

    ((CollapsingToolbarLayout) findViewById(R.id.collapsing_toolbar_layout)).setTitle("Eclairs");

    }
}

回答1:

I assume the parent of your layout is a CoordinatorLayout.

To make the CoordiantorLayout work correct use a NestedScrollView instead of a simple ScrollView.

来源：https://stackoverflow.com/questions/38792976/parallax-scrolling-collapsable-toolbar-in-android

标签

android

toolbar

parallax

android-collapsingtoolbarlayout