CoordinatorLayout简述
作为Android的控件, CoordinatorLayout已经加入最新的HelloWorld项目中, 也是Material风格的重要组件, 协调(Coordinate)其他组件, 实现联动. 那么让我们来看看这个动画效果怎么用吧?
1. 准备
首先新建HelloWorld项目.
在项目的build.gradle文件中, 引入头像控件库和CardView库, 在本例中会使用.
compile 'de.hdodenhof:circleimageview:1.3.0'
compile 'com.android.support:cardview-v7:23.1.0'
compile 'com.jakewharton:butterknife:7.0.1'2. 页面
在activity_main.xml中, 保留CoordinatorLayout和AppBarLayout, 重新编写页面.
android:fitsSystemWindows="true"这句也需要去掉, 本例需要保留最上面的状态栏(status bar), 这个属性会导致重叠, 默认false.
activity_main.xml代码
<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" android:fitsSystemWindows="true" tools:context=".MainActivity">
<android.support.design.widget.AppBarLayout android:layout_width="match_parent" android:layout_height="wrap_content" android:theme="@style/AppTheme.AppBarOverlay">
</android.support.design.widget.AppBarLayout>
</android.support.design.widget.CoordinatorLayout>修改主题颜色, 粉色符合风格
<color name="colorPrimary">#FFCCCC</color>
<color name="colorPrimaryDark">#FF00FF</color>在AppBarLayout中, 添加CollapsingToolbarLayout控件, CollapsingToolbar会滚动消失, 被ToolBar替换, 实现滚动动画.
<android.support.design.widget.CollapsingToolbarLayout android:layout_width="match_parent" android:layout_height="450dp" app:layout_scrollFlags="scroll|exitUntilCollapsed|snap">
</android.support.design.widget.CollapsingToolbarLayout>
app:layout_scrollFlags的属性, scroll滑动, exitUntilCollapsed退出到最小, snap自动滑动动画, 定义CollapsingToolbarLayout的滑动属性.
CollapsingToolbarLayout划分两部分, 一部分大图, 一部分文字.
<ImageView android:layout_width="match_parent" android:layout_height="300dp" android:scaleType="centerCrop" android:src="@drawable/large" app:layout_collapseMode="parallax" />
<FrameLayout android:layout_width="match_parent" android:layout_height="150dp" android:layout_gravity="bottom|center_horizontal" android:background="@color/colorPrimary" app:layout_collapseMode="parallax">
<LinearLayout android:layout_width="wrap_content" android:layout_height="wrap_content" android:orientation="vertical" android:layout_gravity="center">
<TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_gravity="center_horizontal" android:gravity="bottom|center" android:text="@string/person_name" android:textColor="@android:color/white" android:textSize="30sp" />
<TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_gravity="center_horizontal" android:layout_marginTop="4dp" android:text="@string/person_title" android:textColor="@android:color/white"/>
</LinearLayout>
</FrameLayout>
app:layout_collapseMode="parallax"折叠时的视差效果, 自动滑动.
效果
添加NestedScrollView, 文字的滚动视图.
<android.support.v4.widget.NestedScrollView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:scrollbars="none"
app:behavior_overlapTop="30dp"
app:layout_behavior="@string/appbar_scrolling_view_behavior">
<android.support.v7.widget.CardView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="8dp"
app:cardElevation="8dp"
app:contentPadding="16dp">
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:lineSpacingExtra="8dp"
android:text="@string/person_intro"/>
</android.support.v7.widget.CardView>
</android.support.v4.widget.NestedScrollView>
app:behavior_overlapTop="30dp", The amount that the scrolling view should overlap the bottom of any AppBarLayout. 使ScrollView压在AppBarLayout上面一段长度.
添加ToolBar, 滚动结束的效果图.
<android.support.v7.widget.Toolbar
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="@color/colorPrimary"
app:layout_anchor="@id/main_fl_title"
app:theme="@style/ThemeOverlay.AppCompat.Dark">
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:orientation="horizontal">
<Space
android:layout_width="@dimen/image_final_width"
android:layout_height="@dimen/image_final_width" />
<TextView
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:gravity="center_vertical"
android:text="@string/person_name"
android:textColor="@android:color/white"
android:textSize="20sp"/>
</LinearLayout>
</android.support.v7.widget.Toolbar>ToolBar是工具栏, 滑动完成时, 在最上部显示.
Space预留头像的位置.
圆形头像CircleImageView显示(使用第三方库)
<de.hdodenhof.circleimageview.CircleImageView
android:layout_width="120dp"
android:layout_height="120dp"
android:layout_gravity="center"
android:src="@drawable/small"
app:border_color="@android:color/white"
app:border_width="2dp"
app:layout_behavior=".AvatarImageBehavior" />头像控件的滑动行为是自定义的类, 具体行为参考注释. 判断起始和终止位置, child和dependency视图联动, 这里是图像视图和Toolbar联动.
/** * 图片控件位置动画 * * @author wangchenlong */
@SuppressWarnings("unused")
public class AvatarImageBehavior extends CoordinatorLayout.Behavior<CircleImageView> {
private final static float MIN_AVATAR_PERCENTAGE_SIZE = 0.3f;
private final static int EXTRA_FINAL_AVATAR_PADDING = 80;
private int mStartYPosition; // 起始的Y轴位置
private int mFinalYPosition; // 结束的Y轴位置
private int mStartHeight; // 开始的图片高度
private int mFinalHeight; // 结束的图片高度
private int mStartXPosition; // 起始的X轴高度
private int mFinalXPosition; // 结束的X轴高度
private float mStartToolbarPosition; // Toolbar的起始位置
private final Context mContext;
private float mAvatarMaxSize;
public AvatarImageBehavior(Context context, AttributeSet attrs) {
mContext = context;
init();
}
private void init() {
bindDimensions();
}
private void bindDimensions() {
mAvatarMaxSize = mContext.getResources().getDimension(R.dimen.image_width);
}
@Override
public boolean layoutDependsOn(CoordinatorLayout parent, CircleImageView child, View dependency) {
// 依赖Toolbar控件
return dependency instanceof Toolbar;
}
@Override
public boolean onDependentViewChanged(CoordinatorLayout parent, CircleImageView child, View dependency) {
// 初始化属性
shouldInitProperties(child, dependency);
// 最大滑动距离: 起始位置-状态栏高度
final int maxScrollDistance = (int) (mStartToolbarPosition - getStatusBarHeight());
// 滑动的百分比
float expandedPercentageFactor = dependency.getY() / maxScrollDistance;
// Y轴距离
float distanceYToSubtract = ((mStartYPosition - mFinalYPosition)
* (1f - expandedPercentageFactor)) + (child.getHeight() / 2);
// X轴距离
float distanceXToSubtract = ((mStartXPosition - mFinalXPosition)
* (1f - expandedPercentageFactor)) + (child.getWidth() / 2);
// 高度减小
float heightToSubtract = ((mStartHeight - mFinalHeight) * (1f - expandedPercentageFactor));
// 图片位置
child.setY(mStartYPosition - distanceYToSubtract);
child.setX(mStartXPosition - distanceXToSubtract);
// 图片大小
CoordinatorLayout.LayoutParams lp = (CoordinatorLayout.LayoutParams) child.getLayoutParams();
lp.width = (int) (mStartHeight - heightToSubtract);
lp.height = (int) (mStartHeight - heightToSubtract);
child.setLayoutParams(lp);
return true;
}
/** * 初始化动画值 * * @param child 图片控件 * @param dependency ToolBar */
private void shouldInitProperties(CircleImageView child, View dependency) {
// 图片控件中心
if (mStartYPosition == 0)
mStartYPosition = (int) (child.getY() + (child.getHeight() / 2));
// Toolbar中心
if (mFinalYPosition == 0)
mFinalYPosition = (dependency.getHeight() / 2);
// 图片高度
if (mStartHeight == 0)
mStartHeight = child.getHeight();
// Toolbar缩略图高度
if (mFinalHeight == 0)
mFinalHeight = mContext.getResources().getDimensionPixelOffset(R.dimen.image_final_width);
// 图片控件水平中心
if (mStartXPosition == 0)
mStartXPosition = (int) (child.getX() + (child.getWidth() / 2));
// 边缘+缩略图宽度的一半
if (mFinalXPosition == 0)
mFinalXPosition = mContext.getResources().getDimensionPixelOffset(R.dimen.abc_action_bar_content_inset_material) + (mFinalHeight / 2);
// Toolbar的起始位置
if (mStartToolbarPosition == 0)
mStartToolbarPosition = dependency.getY() + (dependency.getHeight() / 2);
}
// 获取状态栏高度
public int getStatusBarHeight() {
int result = 0;
int resourceId = mContext.getResources().getIdentifier("status_bar_height", "dimen", "android");
if (resourceId > 0) {
result = mContext.getResources().getDimensionPixelSize(resourceId);
}
return result;
}
}添加需要使用的id, activity_main.xml如下
<?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"
android:fitsSystemWindows="false"
tools:context=".MainActivity">
<android.support.design.widget.AppBarLayout
android:id="@+id/main_abl_app_bar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar">
<android.support.design.widget.CollapsingToolbarLayout
android:layout_width="match_parent"
android:layout_height="450dp"
app:layout_scrollFlags="scroll|exitUntilCollapsed|snap">
<ImageView
android:id="@+id/main_iv_placeholder"
android:layout_width="match_parent"
android:layout_height="300dp"
android:scaleType="centerCrop"
android:src="@drawable/large"
app:layout_collapseMode="parallax" />
<FrameLayout
android:id="@+id/main_fl_title"
android:layout_width="match_parent"
android:layout_height="150dp"
android:layout_gravity="bottom|center_horizontal"
android:background="@color/colorPrimary"
app:layout_collapseMode="parallax">
<LinearLayout
android:id="@+id/main_ll_title_container"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:orientation="vertical">
<TextView
android:layout_marginTop="@dimen/title_margin"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:gravity="bottom|center"
android:text="@string/person_name"
android:textColor="@android:color/white"
android:textSize="30sp"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:layout_marginTop="4dp"
android:text="@string/person_title"
android:textColor="@android:color/white" />
</LinearLayout>
</FrameLayout>
</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:scrollbars="none"
app:behavior_overlapTop="30dp"
app:layout_behavior="@string/appbar_scrolling_view_behavior">
<android.support.v7.widget.CardView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="8dp"
app:cardElevation="8dp"
app:contentPadding="16dp">
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:lineSpacingExtra="8dp"
android:text="@string/person_intro" />
</android.support.v7.widget.CardView>
</android.support.v4.widget.NestedScrollView>
<android.support.v7.widget.Toolbar
android:id="@+id/main_tb_toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="@color/colorPrimary"
app:layout_anchor="@id/main_fl_title"
app:theme="@style/ThemeOverlay.AppCompat.Dark">
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:orientation="horizontal">
<Space
android:layout_width="@dimen/image_final_width"
android:layout_height="@dimen/image_final_width" />
<TextView
android:id="@+id/main_tv_title"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_marginLeft="8dp"
android:gravity="center_vertical"
android:text="@string/person_name"
android:textColor="@android:color/white"
android:textSize="20sp"
android:visibility="invisible"/>
</LinearLayout>
</android.support.v7.widget.Toolbar>
<de.hdodenhof.circleimageview.CircleImageView
android:layout_width="@dimen/image_width"
android:layout_height="@dimen/image_width"
android:layout_gravity="center"
android:src="@drawable/small"
app:border_color="@android:color/white"
app:border_width="2dp"
app:layout_behavior=".AvatarImageBehavior" />
</android.support.design.widget.CoordinatorLayout>效果
3. 逻辑
在onCreate里面设置滑动逻辑, 设置两个动画: 监听AppBar的滑动, 处理Toolbar和Title的显示; 自动滑动效果.
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ButterKnife.bind(this);
mTbToolbar.setTitle("");
// AppBar的监听
mAblAppBar.addOnOffsetChangedListener(new AppBarLayout.OnOffsetChangedListener() {
@Override
public void onOffsetChanged(AppBarLayout appBarLayout, int verticalOffset) {
int maxScroll = appBarLayout.getTotalScrollRange();
float percentage = (float) Math.abs(verticalOffset) / (float) maxScroll;
handleAlphaOnTitle(percentage);
handleToolbarTitleVisibility(percentage);
}
});
initParallaxValues(); // 自动滑动效果
}根据滑动百分比, 设置Title和Toolbar的显示与消失, 使用Alpha动画.
// 处理ToolBar的显示
private void handleToolbarTitleVisibility(float percentage) {
if (percentage >= PERCENTAGE_TO_SHOW_TITLE_AT_TOOLBAR) {
if (!mIsTheTitleVisible) {
startAlphaAnimation(mTvToolbarTitle, ALPHA_ANIMATIONS_DURATION, View.VISIBLE);
mIsTheTitleVisible = true;
}
} else {
if (mIsTheTitleVisible) {
startAlphaAnimation(mTvToolbarTitle, ALPHA_ANIMATIONS_DURATION, View.INVISIBLE);
mIsTheTitleVisible = false;
}
}
}
// 控制Title的显示
private void handleAlphaOnTitle(float percentage) {
if (percentage >= PERCENTAGE_TO_HIDE_TITLE_DETAILS) {
if (mIsTheTitleContainerVisible) {
startAlphaAnimation(mLlTitleContainer, ALPHA_ANIMATIONS_DURATION, View.INVISIBLE);
mIsTheTitleContainerVisible = false;
}
} else {
if (!mIsTheTitleContainerVisible) {
startAlphaAnimation(mLlTitleContainer, ALPHA_ANIMATIONS_DURATION, View.VISIBLE);
mIsTheTitleContainerVisible = true;
}
}
}
// 设置渐变的动画
public static void startAlphaAnimation(View v, long duration, int visibility) {
AlphaAnimation alphaAnimation = (visibility == View.VISIBLE)
? new AlphaAnimation(0f, 1f)
: new AlphaAnimation(1f, 0f);
alphaAnimation.setDuration(duration);
alphaAnimation.setFillAfter(true);
v.startAnimation(alphaAnimation);
}自动滑动动画, 当到一定比例时展开或关闭.
// 设置自动滑动的动画效果
private void initParallaxValues() {
CollapsingToolbarLayout.LayoutParams petDetailsLp =
(CollapsingToolbarLayout.LayoutParams) mIvPlaceholder.getLayoutParams();
CollapsingToolbarLayout.LayoutParams petBackgroundLp =
(CollapsingToolbarLayout.LayoutParams) mFlTitleContainer.getLayoutParams();
petDetailsLp.setParallaxMultiplier(0.9f);
petBackgroundLp.setParallaxMultiplier(0.3f);
mIvPlaceholder.setLayoutParams(petDetailsLp);
mFlTitleContainer.setLayoutParams(petBackgroundLp);
}最终逻辑
public class MainActivity extends AppCompatActivity {
// 控制ToolBar的变量
private static final float PERCENTAGE_TO_SHOW_TITLE_AT_TOOLBAR = 0.9f;
private static final float PERCENTAGE_TO_HIDE_TITLE_DETAILS = 0.3f;
private static final int ALPHA_ANIMATIONS_DURATION = 200;
private boolean mIsTheTitleVisible = false;
private boolean mIsTheTitleContainerVisible = true;
@Bind(R.id.main_iv_placeholder)
ImageView mIvPlaceholder; // 大图片
@Bind(R.id.main_ll_title_container)
LinearLayout mLlTitleContainer; // Title的LinearLayout
@Bind(R.id.main_fl_title)
FrameLayout mFlTitleContainer; // Title的FrameLayout
@Bind(R.id.main_abl_app_bar)
AppBarLayout mAblAppBar; // 整个可以滑动的AppBar
@Bind(R.id.main_tv_toolbar_title)
TextView mTvToolbarTitle; // 标题栏Title
@Bind(R.id.main_tb_toolbar)
Toolbar mTbToolbar; // 工具栏
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ButterKnife.bind(this);
mTbToolbar.setTitle("");
// AppBar的监听
mAblAppBar.addOnOffsetChangedListener(new AppBarLayout.OnOffsetChangedListener() {
@Override
public void onOffsetChanged(AppBarLayout appBarLayout, int verticalOffset) {
int maxScroll = appBarLayout.getTotalScrollRange();
float percentage = (float) Math.abs(verticalOffset) / (float) maxScroll;
handleAlphaOnTitle(percentage);
handleToolbarTitleVisibility(percentage);
}
});
initParallaxValues(); // 自动滑动效果
}
// 设置自动滑动的动画效果
private void initParallaxValues() {
CollapsingToolbarLayout.LayoutParams petDetailsLp =
(CollapsingToolbarLayout.LayoutParams) mIvPlaceholder.getLayoutParams();
CollapsingToolbarLayout.LayoutParams petBackgroundLp =
(CollapsingToolbarLayout.LayoutParams) mFlTitleContainer.getLayoutParams();
petDetailsLp.setParallaxMultiplier(0.9f);
petBackgroundLp.setParallaxMultiplier(0.3f);
mIvPlaceholder.setLayoutParams(petDetailsLp);
mFlTitleContainer.setLayoutParams(petBackgroundLp);
}
// 处理ToolBar的显示
private void handleToolbarTitleVisibility(float percentage) {
if (percentage >= PERCENTAGE_TO_SHOW_TITLE_AT_TOOLBAR) {
if (!mIsTheTitleVisible) {
startAlphaAnimation(mTvToolbarTitle, ALPHA_ANIMATIONS_DURATION, View.VISIBLE);
mIsTheTitleVisible = true;
}
} else {
if (mIsTheTitleVisible) {
startAlphaAnimation(mTvToolbarTitle, ALPHA_ANIMATIONS_DURATION, View.INVISIBLE);
mIsTheTitleVisible = false;
}
}
}
// 控制Title的显示
private void handleAlphaOnTitle(float percentage) {
if (percentage >= PERCENTAGE_TO_HIDE_TITLE_DETAILS) {
if (mIsTheTitleContainerVisible) {
startAlphaAnimation(mLlTitleContainer, ALPHA_ANIMATIONS_DURATION, View.INVISIBLE);
mIsTheTitleContainerVisible = false;
}
} else {
if (!mIsTheTitleContainerVisible) {
startAlphaAnimation(mLlTitleContainer, ALPHA_ANIMATIONS_DURATION, View.VISIBLE);
mIsTheTitleContainerVisible = true;
}
}
}
// 设置渐变的动画
public static void startAlphaAnimation(View v, long duration, int visibility) {
AlphaAnimation alphaAnimation = (visibility == View.VISIBLE)
? new AlphaAnimation(0f, 1f)
: new AlphaAnimation(1f, 0f);
alphaAnimation.setDuration(duration);
alphaAnimation.setFillAfter(true);
v.startAnimation(alphaAnimation);
}
}Github下载地址
这样联动效果就已经显示出来了, 在AppBar中Toolbar和Title之间的关系, 符合Material的风格, 给用户更多的体验. 既然已经集成到HelloWorld中, 说明Android是极力推荐使用CoordinatorLayout这种风格的, 那我们就Enjoy it吧.