如何实现“动画 CollapsingToolbar”？

Question

基本上，我想知道在使用 RecyclerView 时如何实现一种“动画 CollapsingToolbar”。请注意，它是用引号引起来的，因为我没有附加到作为 CollapsingToolbar 的解决方案，但这是迄今为止我能找到的最接近我想要的东西。基本上，我想制作一个工具栏，其中包含我的应用程序的标题，以及带有一些字符串的副标题，后跟一个 int（作为字符串类型）。当我向上滚动时，我希望字符串淡出，但保留 int 并向上移动到与应用标题相同的级别。

（请原谅粗图）

我查看了this solution，但它依赖于 ListView。我也看过this solution，但是我看不出我如何能够按照自己的意愿自定义动画。 This repo 看起来可以工作，但它有一堆错误，无法编译。

所以基本上，总而言之，我正在寻找如何以我上面描述的方式为工具栏设置动画，用你认为最好的任何方式，不一定是折叠工具栏。

Answer 1

查看此CoordinatorLayout

<android.support.design.widget.CoordinatorLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true">

    <android.support.design.widget.AppBarLayout
        android:id="@+id/app_bar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:paddingTop="5dp"
        android:paddingBottom="30dp"
        android:theme="@style/AppTheme.AppBarOverlay"
        >

        <abysmel.com.collapsibletoolbarhelper.widgets.CollapsibleToolbarHelper
            android:id="@+id/toolbar_layout"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            app:layout_scrollFlags="scroll|exitUntilCollapsed"
            android:gravity="center_vertical"
            android:layout_marginTop="10dp"
            android:background="@android:color/transparent"
            >

            <!--Note that the position has to be set with respect to the collapsed toolbar. So,
                aligning it in center initially (centerInParent="true") will NOT work as it will remain
                at its position even after the Toolbar collapses. Also note that the initially set the
                alpha of the view to zero and NOT the visibility to gone, as the view will then have never
                been drawn which will throw all calculations haywire for show_on_collapse. Wish there
                was a better way to do this-->
            <ImageView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:id="@+id/hello.img"
                android:src="@mipmap/hello"
                android:layout_marginLeft="10dp"
                android:alpha="0"
                app:layout_marginTopPercent = "3%"
                app:collapseMode="show_on_collapse"/>

            <!-- Title -->
            <abysmel.com.collapsibletoolbarhelper.widgets.CollapsibleTextLayout
                android:id="@+id/hello.text"
                android:layout_height="wrap_content"
                android:layout_width="wrap_content"
                app:layout_widthPercent="59%"
                android:layout_alignParentLeft="true"
                app:layout_marginTopPercent = "1%"
                app:layout_marginBottomPercent = "1%"
                app:layout_marginLeftPercent="5%"
                android:textColor="@android:color/white"
                app:collapseMode="pin_on_scroll"
                app:textToShow = "Hello World"
                app:expandedTextColor = "@android:color/white"
                app:collapsedTextColor = "@android:color/white"
                app:typefaceFamilyPrimary = "sans-serif-light"
                app:typefaceFamilySecondary = "sans-serif-medium"
                app:isMultiFaceted="true"
                app:typefaceSplitPosition="5"
                app:expandedTextSize = "62dp"
                app:collapsedTextSize = "32dp"
                app:maxExpandedTextSize = "62dp"
                />

            <!-- The hello number edit button -->
            <ImageView
                android:id="@+id/hello.edit"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_alignParentRight="true"
                app:layout_marginTopPercent = "3%"
                app:layout_marginBottomPercent = "1%"
                app:layout_marginRightPercent = "4%"
                android:layout_marginLeft="10dp"
                android:src="@mipmap/pencil"
                app:collapseMode="hide_on_collapse"/>

            <!-- The hello Number -->
            <TextView
                android:id="@+id/hello.number"
                android:layout_height="wrap_content"
                android:layout_width="wrap_content"
                app:layout_widthPercent="40%"
                app:layout_marginTopPercent = "1%"
                app:layout_marginBottomPercent = "1%"
                app:layout_marginRightPercent = "1%"
                android:layout_toLeftOf="@id/hello.edit"
                android:layout_toRightOf="@id/hello.text"
                android:gravity="end"
                android:text="@string/hello_no_sign"
                android:textColor="@android:color/white"
                android:textSize="@dimen/hello_no_size"
                app:collapseMode="pin_on_scroll"/>



            <!-- Version -->
            <TextView
                android:id="@+id/version"
                app:layout_widthPercent="40%"
                android:layout_height="wrap_content"
                android:layout_width="wrap_content"
                android:layout_below="@id/hello.text"
                android:layout_marginTop="5dp"
                android:layout_alignParentLeft="true"
                app:layout_marginLeftPercent="5%"
                android:text="@string/version"
                android:textColor="@android:color/white"
                android:textSize="@dimen/version_no_size"
                app:collapseMode="parallax_on_scroll"
                 />

            <!-- E-mail Address -->
            <TextView
                android:id="@+id/hello.address"
                app:layout_widthPercent="40%"
                android:layout_height="wrap_content"
                android:layout_width="wrap_content"
                android:layout_below="@id/hello.number"
                android:layout_alignParentRight="true"
                android:gravity="end"
                app:layout_marginRightPercent="5%"
                android:text="@string/emailaddress"
                android:textColor="@android:color/white"
                android:textSize="@dimen/mail_address_size"
                app:collapseMode="parallax_on_scroll"
                 />
        </abysmel.com.collapsibletoolbarhelper.widgets.CollapsibleToolbarHelper>
    </android.support.design.widget.AppBarLayout>
</android.support.design.widget.CoordinatorLayout>

https://github.com/opacapp/multiline-collapsingtoolbar