1. CoordinatorLayout
我们通常把CoordinatorLayout作为顶层布局来协调其子布局之间的动画效果。
子view1在布局中通过设置behavior属性与子view2关联,当移动view2的时候view1产生相应的效果,而这个效果具体是怎么样的由behavior类来决定。我们把view1叫做Child,view2叫做Dependency,Child跟随Dependency的变化而变化(CoordinatorLayout通过设置子View的 Behaviors来调度子View,使两个互相关联的view之间高度解耦)。
系统控件中往往把behavior作为内部类自己实现,比如AppBarLayout.Behavior, AppBarLayout.ScrollingViewBehavior,和FloatingActionButton.Behavior等。
当然我们也可以自定义Behavior,步骤非常简单:
- 首先在代码中自定义Behavior,一般实现如下两个方法,注意泛型参数传Child的类型。
public class MyBehavior extends CoordinatorLayout.Behavior<View>{
/**
* Determine whether the supplied child view has another specific sibling view as a
* layout dependency.
* @param parent the parent view of the given child
* @param child the child view to test
* @param dependency the proposed dependency of child
* @return true if child's layout depends on the proposed dependency's layout,
* false otherwise
*/
@Override
public boolean layoutDependsOn(CoordinatorLayout parent, View child, View dependency) {
//如果dependency是xxView的实例,说明它就是我们所需要的Dependency
return dependency instanceof xxView;
}
/**
* Respond to a change in a child's dependent view
* @return true if the Behavior changed the child view's size or position, false otherwise
*
* 当dependency发生改变时(位置、宽高等),执行这个函数
* 返回true表示child的位置或者是宽高要发生改变,否则就返回false
*/
@Override
public boolean onDependentViewChanged(CoordinatorLayout parent, View child, View dependency) {
// do something
return true;
}
}
- 在布局中使用
<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout
.......
>
<View
.......
app:layout_behavior="xxx.xx.xxx.MyBehavior" />
<xxView
.......
/>
</>
1.1 FloatingActionButton & Snackbar
FloatingActionButton把它当成一个自带阴影和填充颜色的ImageView来使用皆可.
Snackbar是Android Support Design Library库支持的来替代Toast的一个控件。Snackbar使用的时候需要一个控件容器用来容纳Snackbar.官方推荐使用CoordinatorLayout。
像Toast一样使用:
Snackbar.make(view, "SnackbarTest", Snackbar.LENGTH_LONG).show();
Snackbar还支持添加一个按钮的,其可以如下构造:
Snackbar.make(view, "SnackbarTest",Snackbar.LENGTH_LONG).setAction("Action", new View.OnClickListener() {
@Override
public void onClick(View v) {
Snackbar.make(view,"ActionClick",Snackbar.LENGTH_LONG).show();
}
}).show();
1.2 CoordinatorLayout +FloatingActionButton+snackbar
FloatingActionButton默认使用FloatingActionButton.Behavior,FloatingActionButton会随着snackbar向上移动,下面看效果:
布局:
<android.support.design.widget.CoordinatorLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/coordinatorLayout"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.design.widget.FloatingActionButton
android:id="@+id/floatingActionButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="end|bottom"
android:layout_margin="20dp"
android:src="@drawable/ic_right"
>
</android.support.design.widget.FloatingActionButton>
</android.support.design.widget.CoordinatorLayout>
代码:
@InjectView(R.id.floatingActionButton)
FloatingActionButton floatingActionButton;
@InjectView(R.id.coordinatorLayout)
CoordinatorLayout coordinatorLayout;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ButterKnife.inject(this);
}
@OnClick(R.id.floatingActionButton)
public void onClick() {
Snackbar.make(coordinatorLayout, "SnackbarTest",Snackbar.LENGTH_LONG).setAction("Action", new View.OnClickListener() {
@Override
public void onClick(View v) {
Snackbar.make(coordinatorLayout,"ActionClick",Snackbar.LENGTH_LONG).show();
}
}).show();
}
2. AppBarLayout
AppBarLayout继承自LinearLayout,布局方向为垂直方向。所以你可以把它当成垂直布局的LinearLayout来使用。当CoordinatorLayout发生滚动手势的时候,AppBarLayout的子View通过在布局中设置app:layout_scrollFlags属性,来发生相应的滚动。
简单的来说,AppBarLayout可以协调其子view随着同为CoordinatorLayout子view的兄弟view发生滚动手势的时候发生相应滚动。app:layout_scrollFlags属性有四个枚举值:
- scroll:
this flag should be set for all views that want to scroll off the screen - for views that do not use this flag, they’ll remain pinned to the top of the screen (所有想滚动出屏幕的view都需要设置这个flag, 没有设置这个flag的view将被固定在屏幕顶部)
-
enterAlways:
this flag ensures that any downward scroll will cause this view to become visible, enabling the ‘quick return’ pattern (设置这个flag时,向下的滚动都会导致该view变为可见,启用快速“返回模式”) -
enterAlwaysCollapsed:
When your view has declared a minHeight and you use this flag, your View will only enter at its minimum height , only re-expanding to its full height when the scrolling view has reached it’stop.(当你的视图已经设置minHeight属性又使用此标志时,你的视图只能已最小高度进入,只有当滚动视图到达顶部时才扩大到完整高度) -
exitUntilCollapsed:
this flag causes the view to scroll off until it is ‘collapsed’ (its minHeight) before exiting(滚动退出屏幕,最后折叠在顶端)
2.1CoordinatorLayout+AppBarLayout+Toolbar+TabLayout+ViewPager+RecyclerView+CardView
效果图:
1.gif
在AppBarLayout中嵌套Toolbar和TabLayout,与ViewPager协调滚动。
activity_main.xml
<android.support.design.widget.CoordinatorLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="@+id/coordinatorLayout"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.design.widget.AppBarLayout
android:id="@+id/appBarLayout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar">
<android.support.v7.widget.Toolbar
android:id="@+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary"
app:layout_scrollFlags="scroll|enterAlways"
/>
<android.support.design.widget.TabLayout
android:id="@+id/tabLayout"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</android.support.design.widget.AppBarLayout>
<android.support.v4.view.ViewPager
android:id="@+id/viewpager"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="@string/appbar_scrolling_view_behavior" />
</android.support.design.widget.CoordinatorLayout>
MainActivity.java
public class MainActivity extends AppCompatActivity {
@InjectView(R.id.toolbar)
Toolbar toolbar;
@InjectView(R.id.tabLayout)
TabLayout tabLayout;
@InjectView(R.id.viewpager)
ViewPager viewpager;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ButterKnife.inject(this);
toolbar.setTitle("This is Title");
toolbar.setSubtitle("subTitle");
setSupportActionBar(toolbar);
viewpager.setAdapter(new FragmentPagerAdapter(getSupportFragmentManager()) {
@Override
public int getCount() {
return 3;
}
@Override
public Fragment getItem(int position) {
switch (position) {
case 0:
return new Fragment_a();
case 1:
return new Fragment_a();
case 2:
return new Fragment_a();
default:
return new Fragment_a();
}
}
@Override
public CharSequence getPageTitle(int position) {
switch (position) {
case 0:
return "page one";
case 1:
return "page two";
case 2:
return "page three";
default:
return "page one";
}
}
});
tabLayout.setupWithViewPager(viewpager);
}
}
Fragment_a.java
public class Fragment_a extends Fragment {
@InjectView(R.id.recyclerView)
RecyclerView recyclerView;
List<String> datas;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment, container, false);
ButterKnife.inject(this, view);
recyclerView.setLayoutManager(new StaggeredGridLayoutManager(2,StaggeredGridLayoutManager.VERTICAL));
initData();
RecyclerViewAdapter adapter=new RecyclerViewAdapter(datas);
recyclerView.setAdapter(adapter);
SpacesItemDecoration decoration=new SpacesItemDecoration(16);
recyclerView.addItemDecoration(decoration);
adapter.setOnItemClickListener(new RecyclerViewAdapter.OnRecyclerViewItemClickListener() {
@Override
public void onItemClick(View v) {
Snackbar.make(v, "Click Item "+v.getTag(), Snackbar.LENGTH_LONG).show();
}
});
return view;
}
public class SpacesItemDecoration extends RecyclerView.ItemDecoration {
private int space;
public SpacesItemDecoration(int space) {
this.space=space;
}
@Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
outRect.left=space;
outRect.right=space;
outRect.bottom=space;
if(parent.getChildAdapterPosition(view)==0){
outRect.top=space;
}
}
}
public void initData(){
datas = new ArrayList<String>();
for(int i =0;i<17;i++){
datas.add("item "+i);
}
}
@Override
public void onDestroyView() {
super.onDestroyView();
ButterKnife.reset(this);
}
}
RecyclerViewAdapter.java
public class RecyclerViewAdapter extends RecyclerView.Adapter<RecyclerViewAdapter.ViewHolder>{
private List<String> datas;
public static interface OnRecyclerViewItemClickListener {
void onItemClick(View view);
}
private OnRecyclerViewItemClickListener mOnItemClickListener = null;
public void setOnItemClickListener(OnRecyclerViewItemClickListener listener) {
mOnItemClickListener = listener;
}
public RecyclerViewAdapter(List<String> datas) {
this.datas=datas;
}
@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType)
{
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.recyclerview_item,parent,false);
v.setOnClickListener(new View.OnClickListener(){
@Override
public void onClick(View v) {
mOnItemClickListener.onItemClick(v);
}
});
ViewHolder vh = new ViewHolder(v);
return vh;
}
@Override
public void onBindViewHolder(ViewHolder holder, int position) {
holder.item.setTag(position);
holder.tv.setText(datas.get(position));
}
class ViewHolder extends RecyclerView.ViewHolder
{
public View item;
public TextView tv;
public ViewHolder(View view){
super(view);
item = view;
tv = (TextView) view.findViewById(R.id.text);
}
}
@Override
public int getItemCount()
{
return datas.size();
}
public void addItem(String s, int position) {
datas.add(position, s);
notifyItemInserted(position);
}
public void removeItem(final int position) {
datas.remove(position);
notifyItemRemoved(position);
}
}
recyclerview_item.xml
<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:foreground="?android:attr/selectableItemBackground"
android:layout_width="match_parent"
android:layout_height="100dp"
app:cardCornerRadius="7dp"
app:cardElevation="7dp"
android:clickable="true"
>
<TextView
android:text="TextView"
android:textColor="#7A67EE"
android:layout_gravity="center"
android:id="@+id/text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="20sp" />
</android.support.v7.widget.CardView>
Toolbar可以看做是android 5.0以后用来替代ActionBar的控件,所以我们在使用Toolbar的时候,需要先在styles.xml文件中的AppTheme标签中设置不使用主题自带的ActionBar,加入如下两行代码:
<item name="windowActionBar">false</item>
<item name="windowNoTitle">true</item>
CoordinatorLayout中带有滚动属性的子View(这里的ViewPager)需要设置app:layout_behavior属性。
app:layout_behavior="@string/appbar_scrolling_view_behavior"
把ViewPager的滚动和AppBarLayout相关联起来。然后给AppBarLayout中需要产生相应滚动的子view(这里的Toolbar)设置app:layout_scrollFlags属性。
本demo下载: http://download.csdn.net/detail/amazing7/9577677
3. CollapsingToolbarLayout
CollapsingToolbarLayout主要是用于实现折叠效果。它需要放在AppBarLayout布局里面,并且作为AppBarLayout的直接子View。它继承至FrameLayout,给它设置layout_scrollFlags,它可以控制包含在CollapsingToolbarLayout中的控件在响应layout_behavior事件时作出相应的scrollFlags滚动事件(通过给CollapsingToolbarLayout的子view设置app:layout_collapseMode属性)。
CollapsingToolbarLayout的几个属性:
app:collapsedTitleTextAppearance 在收缩时Title文字外形设置
app:expandedTitleTextAppearance 展开时Title文字外形的设置
app:contentScrim 标题文字停留在顶部时候背景的设置
app:expandedTitleMarginStart 展开时title向左填充的距离
app:expandedTitleMarginEnd 收缩时title向左填充的距离
CollapsingToolbarLayout的子View中通过设置layout_collapseMode属性来响应折叠模式,该属性有两个枚举值:
“pin”:固定模式,在折叠的时候最后固定在顶端
“parallax”:视差模式,在折叠的时候会有个视差折叠的效果
在FloatingActionButton中通过设置以下两个属性,可以使FloatingActionButton跟随CollapsingToolbarLayout的收缩而显示隐藏(所依赖的AppBarLayout的id和相对AppBarLayout的摆放位置)。
app:layout_anchor="@id/appBarLayout"
app:layout_anchorGravity="bottom|right|end"
3.1CoordinatorLayout+AppBarLayout+CollapsingToolbarLayout+Toolbar+NestedScrollView+RecyclerView+FloatingActionButton
效果图:
1.gifactivity_main.xml
<?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"
android:id="@+id/coordinatorLayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true">
<android.support.design.widget.AppBarLayout
android:id="@+id/appBarLayout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:fitsSystemWindows="true"
android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar">
<android.support.design.widget.CollapsingToolbarLayout
android:id="@+id/collapsing_toolbar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:contentScrim="?attr/colorPrimary"
app:expandedTitleMarginEnd="70dp"
app:expandedTitleMarginStart="50dp"
app:layout_scrollFlags="scroll|exitUntilCollapsed">
<ImageView
android:layout_width="match_parent"
android:layout_height="300dp"
android:fitsSystemWindows="true"
android:scaleType="centerCrop"
android:src="@drawable/ic_scu"
app:layout_collapseMode="parallax" />
<android.support.v7.widget.Toolbar
android:id="@+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
app:layout_collapseMode="pin"
app:popupTheme="@style/ThemeOverlay.AppCompat.Light" />
</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"
app:layout_behavior="@string/appbar_scrolling_view_behavior">
<android.support.v7.widget.RecyclerView
android:id="@+id/recyclerView"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</android.support.v4.widget.NestedScrollView>
<android.support.design.widget.FloatingActionButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="20dp"
android:clickable="true"
android:src="@drawable/ic_done"
app:layout_anchor="@id/appBarLayout"
app:layout_anchorGravity="bottom|right|end" />
</android.support.design.widget.CoordinatorLayout>
MainActivity.java
public class MainActivity extends AppCompatActivity {
@InjectView(R.id.toolbar)
Toolbar toolbar;
@InjectView(R.id.collapsing_toolbar)
CollapsingToolbarLayout collapsingToolbar;
@InjectView(R.id.recyclerView)
RecyclerView recyclerView;
List<String> datas;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ButterKnife.inject(this);
setSupportActionBar(toolbar);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
collapsingToolbar.setTitle("Collapsing");
InitRecyclerView();
}
public void InitRecyclerView(){
recyclerView.setLayoutManager(new StaggeredGridLayoutManager(1,StaggeredGridLayoutManager.VERTICAL));
initData();
RecyclerViewAdapter adapter=new RecyclerViewAdapter(datas);
recyclerView.setAdapter(adapter);
SpacesItemDecoration decoration=new SpacesItemDecoration(16);
recyclerView.addItemDecoration(decoration);
adapter.setOnItemClickListener(new RecyclerViewAdapter.OnRecyclerViewItemClickListener() {
@Override
public void onItemClick(View v) {
Snackbar.make(v, "Click Item "+v.getTag(), Snackbar.LENGTH_LONG).show();
}
});
}
public class SpacesItemDecoration extends RecyclerView.ItemDecoration {
private int space;
public SpacesItemDecoration(int space) {
this.space=space;
}
@Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
outRect.left=space;
outRect.right=space;
outRect.bottom=space;
if(parent.getChildAdapterPosition(view)==0){
outRect.top=space;
}
}
}
public void initData(){
datas = new ArrayList<String>();
for(int i =0;i<17;i++){
datas.add("item "+i);
}
}
}
NestedScrollView也可以与AppBarLayout协调滚动,可以把它看出自带Behavior的ScrollView来使用,但是它并没有继承ScrollView,而是继承的FrameLayout。
NestedScrollView通过设置layout_behavior来使AppBarLayout产生滚动关联,CollapsingToolbarLayout作为AppBarLayout的子view通过设置layout_scrollFlags属性来产生滚动响应,CollapsingToolbarLayout的子view通过设置layout_collapseMode属性来响应滚动模式。
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