2020-12-03 Material Design之AppBarLayout

协调布局和AppBarLayout一起使用

1. ToolBar的scrollFlags:

• scrollFlag为scroll | enterAlways

<com.google.android.material.appbar.AppBarLayout
    android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">
    <androidx.appcompat.widget.Toolbar
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        app:title="协调布局"
        app:layout_scrollFlags="scroll|enterAlways"
        android:layout_height="?attr/actionBarSize"
        android:background="?attr/colorPrimary"
        app:titleTextColor="@android:color/white"
        tools:ignore="MissingConstraints" />
</com.google.android.material.appbar.AppBarLayout>

设为scroll|enterAwlays

• scrollFlag为scroll

<com.google.android.material.appbar.AppBarLayout
    android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">
    <androidx.appcompat.widget.Toolbar
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        app:title="协调布局"
        app:layout_scrollFlags="scroll"
        android:layout_height="?attr/actionBarSize"
        android:background="?attr/colorPrimary"
        app:titleTextColor="@android:color/white"
        tools:ignore="MissingConstraints" />
</com.google.android.material.appbar.AppBarLayout>

设为scroll

• scrollFlag为scroll|enterAlways|snap,根据拉伸距离决定ToolBar的拉伸和隐藏

<com.google.android.material.appbar.AppBarLayout
    android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"
    android:layout_width="match_parent"
    android:fitsSystemWindows="true"
    android:layout_height="wrap_content">
    <androidx.appcompat.widget.Toolbar
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        app:title="协调布局"
        app:layout_scrollFlags="scroll|enterAlways|snap"
        android:layout_height="?actionBarSize"
        android:background="?attr/colorPrimary"
        android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"
        app:popupTheme="@style/ThemeOverlay.AppCompat.Light"
        tools:ignore="MissingConstraints" />
</com.google.android.material.appbar.AppBarLayout>

snap

• scrollFlag为enterAlwaysCollapsed，注意scroll及enterAlways，需要设置minHeight

<com.google.android.material.appbar.AppBarLayout
    android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">
    <androidx.appcompat.widget.Toolbar
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        app:title="协调布局"
        app:layout_scrollFlags="scroll|enterAlways|enterAlwaysCollapsed"
        android:layout_height="200dp"
        android:minHeight="50dp"
        android:background="?attr/colorPrimary"
        app:titleTextColor="@android:color/white"
        tools:ignore="MissingConstraints" />
</com.google.android.material.appbar.AppBarLayout>

enterAlwaysCollapsed