高级UI-符合MD的常用控件

在Google提供的控件中，在support-design及v4，v7包中，存在着很多符合MD标准的控件，这里罗列出一些常用的控件

TextInputLayout

这个控件在作为输入框的时候是极其方便及好用的，结合EditText使用

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"android:layout_width="match_parent"android:layout_height="match_parent"xmlns:app="http://schemas.android.com/apk/res-auto"android:orientation="vertical"><android.support.design.widget.TextInputLayoutandroid:layout_width="match_parent"android:layout_height="wrap_content"app:counterEnabled="true"app:counterMaxLength="10"><EditTextandroid:layout_width="match_parent"android:layout_height="wrap_content"android:hint="请输入用户名" /></android.support.design.widget.TextInputLayout><EditTextandroid:layout_width="match_parent"android:layout_height="wrap_content"android:hint="请输入密码" /><Buttonandroid:layout_width="match_parent"android:layout_height="wrap_content"android:text="登录" /></LinearLayout>

效果

SearchView

搜索功能，位于ActionBar的位置
首先需要编写menu布局

<?xml version="1.0" encoding="utf-8"?>
<menu 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"tools:context=".MainActivity"><item android:id="@+id/menu_search"android:orderInCategory="100"app:showAsAction="always"app:actionViewClass="android.support.v7.widget.SearchView"android:title="search"/><item android:id="@+id/menu_share"android:orderInCategory="100"app:showAsAction="ifRoom"android:icon="@android:drawable/ic_menu_share"android:title="share" />
</menu>

然后复写onCreateOptionsMenu()方法

public class MainActivity extends AppCompatActivity {@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);}@Overridepublic boolean onCreateOptionsMenu(Menu menu) {getMenuInflater().inflate(R.menu.main, menu);MenuItem menuItem = menu.findItem(R.id.menu_search);final SearchView searchView = (SearchView) MenuItemCompat.getActionView(menuItem);//显示搜索框//searchView.setIconified(false);//显示搜索框，且其不能被隐藏searchView.setIconifiedByDefault(false);//显示提交按钮，这里可以获取到id，设置自定义图片ImageView icon = (ImageView) searchView.findViewById(R.id.search_go_btn);icon.setImageResource(R.mipmap.ic_launcher);icon.setVisibility(View.VISIBLE);//设置监听icon.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {Toast.makeText(MainActivity.this, searchView.getQuery(), Toast.LENGTH_SHORT).show();}});//获取id，从而设置提示EditText edit = (EditText) searchView.findViewById(R.id.search_src_text);edit.setHint("请输入搜索的内容");searchView.setSubmitButtonEnabled(true);//SearchView还有很多设置监听选项，例如提交监听，文本监听return true;}
}

效果如下：

Toolbar

顶部导航栏。用于显示标题，返回，菜单等，最开始是使用的ActionBar
由于ActionBar的种种使用不便，再加上拓展性差，google后来推出了Toolbar，为了增强其功能，现在还有APPbar可供使用
首先还是要把主题设置为NoActionBar

<resources><!-- Base application theme. --><style name="AppTheme" parent="Theme.AppCompat.Light.NoActionBar"><!-- Customize your theme here. --><item name="colorPrimary">@color/colorPrimary</item><item name="colorPrimaryDark">@color/colorPrimaryDark</item><item name="colorAccent">@color/colorAccent</item></style></resources>

然后使用Toolbar布局，由于ToolBar继承自ViewGroup，所以其是一个容器

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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"tools:context=".MainActivity"><android.support.v7.widget.Toolbarandroid:id="@+id/toolbar"android:layout_width="match_parent"android:layout_height="wrap_content"android:background="?attr/colorPrimary"app:logo="@mipmap/ic_launcher"app:navigationIcon="@drawable/abc_ic_ab_back_material"app:subtitle="子标题"app:subtitleTextColor="@android:color/white"app:title="主标题"app:titleTextColor="@color/colorAccent"><!--<TextView--><!--android:layout_width="wrap_content"--><!--android:layout_height="wrap_content"--><!--android:layout_gravity="center"--><!--android:text="这里是标题"/>--></android.support.v7.widget.Toolbar></LinearLayout>

最后设置Toolbar到活动，并设置监听

public class MainActivity extends AppCompatActivity {private Toolbar toolbar;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);toolbar = findViewById(R.id.toolbar);setSupportActionBar(toolbar);toolbar.setNavigationOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {finish();}});}
}

测试效果如下

接下来实现Toolbar的隐藏效果
这样的效果实现思路就是Toolbar在上层，后面的布局在下层，后面的布局设置padding，然后再滑动过程中监听滑动距离，设置Toolbar的透明度

interface TranslucentListener {//透明度的回调监听 alpha:0~1void onTranlucent(float alpha);
}

自定义ScrollView，在onScrollChanged()中监听

public class MyScrollView extends ScrollView {private TranslucentListener translucentListener;public void setTranslucentListener(TranslucentListener translucentListener) {this.translucentListener = translucentListener;}public MyScrollView(Context context, AttributeSet attrs) {super(context, attrs);}@Overrideprotected void onScrollChanged(int l, int t, int oldl, int oldt) {super.onScrollChanged(l, t, oldl, oldt);if (translucentListener != null) {Log.d("cj5785", "onScrollChanged");int scrollY = getScrollY();int screen_height = getContext().getResources().getDisplayMetrics().heightPixels;//滑出1/3时候完全透明if (scrollY <= screen_height / 3f) {translucentListener.onTranlucent(1 - scrollY / (screen_height / 3f));}}}
}

最后在活动中回调

public class MainActivity extends AppCompatActivity implements TranslucentListener{private Toolbar toolbar;private MyScrollView scrollView;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);toolbar = findViewById(R.id.toolbar);setSupportActionBar(toolbar);toolbar.setNavigationOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {finish();}});scrollView = findViewById(R.id.scroll_view);scrollView.setTranslucentListener(this);}@Overridepublic void onTranlucent(float alpha) {toolbar.setAlpha(alpha);}
}

贴出布局
android:clipToPadding="false" 该控件的绘制范围是否不在Padding里面。false：绘制的时候范围会考虑padding即会往里面缩进
android:clipChildren="false" 子控件是否能不超出padding的区域（比如ScrollView上滑动的时候，child可以滑出该区域）

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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"tools:context=".MainActivity"><com.cj5785.toolbartest.MyScrollViewandroid:id="@+id/scroll_view"android:layout_width="match_parent"android:layout_height="match_parent"android:clipChildren="false"android:clipToPadding="false"android:paddingTop="?attr/actionBarSize"><android.support.v7.widget.LinearLayoutCompatandroid:layout_width="match_parent"android:layout_height="match_parent"android:orientation="vertical"><TextViewandroid:layout_width="match_parent"android:layout_height="200dp"android:background="@android:color/holo_orange_light" /><TextViewandroid:layout_width="match_parent"android:layout_height="200dp"android:background="@android:color/holo_green_light" /><TextViewandroid:layout_width="match_parent"android:layout_height="200dp"android:background="@android:color/holo_blue_light" /><TextViewandroid:layout_width="match_parent"android:layout_height="200dp"android:background="@android:color/holo_red_light" /><TextViewandroid:layout_width="match_parent"android:layout_height="200dp"android:background="@android:color/holo_purple" /></android.support.v7.widget.LinearLayoutCompat></com.cj5785.toolbartest.MyScrollView><android.support.v7.widget.Toolbarandroid:id="@+id/toolbar"android:layout_width="match_parent"android:layout_height="?attr/actionBarSize"android:background="?attr/colorPrimary"app:logo="@mipmap/ic_launcher"app:navigationIcon="@drawable/abc_ic_ab_back_material"app:subtitle="子标题"app:subtitleTextColor="@android:color/white"app:title="主标题"app:titleTextColor="@color/colorAccent"><!--<TextView--><!--android:layout_width="wrap_content"--><!--android:layout_height="wrap_content"--><!--android:layout_gravity="center"--><!--android:text="这里是标题"/>--></android.support.v7.widget.Toolbar></RelativeLayout>

实现效果：

CoordinatorLayout

监听滑动控件的滑动通过Behavior反馈到其他子控件并执行一些动画
这里的滑动控件指的是RecyclerView/NestedScrollView/ViewPager，意味着ListView、ScrollView不行
使用前需要添加support-design依赖

implementation 'com.android.support:design:25.4.0'

布局

<?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"tools:context=".MainActivity"><android.support.v7.widget.RecyclerViewandroid:id="@+id/recycler_view"android:layout_width="match_parent"android:layout_height="match_parent" /><android.support.design.widget.FloatingActionButtonapp:layout_behavior=".FABBehavior"android:layout_width="wrap_content"android:layout_height="wrap_content"android:layout_gravity="bottom|end"android:layout_margin="16dp" /></android.support.design.widget.CoordinatorLayout>

适配器

public class MyAdapter extends RecyclerView.Adapter<MyAdapter.MyViewHolder> {private List<String> list;class MyViewHolder extends RecyclerView.ViewHolder {private TextView textView;public MyViewHolder(View itemView) {super(itemView);textView = (TextView) itemView.findViewById(android.R.id.text1);}}public MyAdapter(List<String> list) {this.list = list;}@Overridepublic MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {LayoutInflater layoutInflater = LayoutInflater.from(parent.getContext());View view = layoutInflater.inflate(android.R.layout.simple_list_item_1,parent,false);MyViewHolder holder = new MyViewHolder(view);return holder;}@Overridepublic void onBindViewHolder(MyViewHolder holder, int position) {holder.textView.setText(list.get(position));}@Overridepublic int getItemCount() {return list.size();}
}

Behavior

public class FABBehavior extends FloatingActionButton.Behavior {private boolean isShow;public FABBehavior(Context context, AttributeSet attrs) {super(context, attrs);}//依赖滑动开始回调@Overridepublic boolean onStartNestedScroll(CoordinatorLayout coordinatorLayout, FloatingActionButton child, View directTargetChild, View target, int nestedScrollAxes) {//nestedScrollAxes 滑动的方向，这里我们依赖recyclerview，只关心其是否垂直滑动return nestedScrollAxes == ViewCompat.SCROLL_AXIS_VERTICAL|| super.onStartNestedScroll(coordinatorLayout, child, directTargetChild, target, nestedScrollAxes);}//依赖滑动过程回调@Overridepublic void onNestedScroll(CoordinatorLayout coordinatorLayout, FloatingActionButton child, View target, int dxConsumed, int dyConsumed, int dxUnconsumed, int dyUnconsumed) {super.onNestedScroll(coordinatorLayout, child, target, dxConsumed, dyConsumed, dxUnconsumed, dyUnconsumed);//根据情况执行动画if (dyConsumed > 0 && isShow) {isShow = false;onHide(child);} else if (dyConsumed < 0) {isShow = true;onShow(child);}}private void onShow(FloatingActionButton fab) {ViewCompat.animate(fab).scaleX(1f).scaleY(1f).start();}private void onHide(FloatingActionButton fab) {ViewCompat.animate(fab).scaleX(0f).scaleY(0f).start();}
}

调用

public class MainActivity extends AppCompatActivity {private List<String> list = new ArrayList<>();private RecyclerView recyclerView;private MyAdapter adapter;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);recyclerView = (RecyclerView) findViewById(R.id.recycler_view);recyclerView.setLayoutManager(new LinearLayoutManager(this));for (int i = 0; i < 100; i++) {list.add("item " + i);}adapter = new MyAdapter(list);recyclerView.setAdapter(adapter);}
}

效果如下，实现了FloatingActionButton上划隐藏，下拉显示

AppBarLayout

AppBarLayout继承自LinearLayout，一般用于导航栏，其常见子控件为Toolbar，但同时又不局限于Toolbar，可以实现导航栏的多种综合效果，其作为容器，里面可以增加布局，按照需要去实现各种效果
这里做一个简单的演示，导航栏通过recyclerview的滑动而显隐的效果
首先依旧是要引入依赖

implementation 'com.android.support:design:25.4.0'

然后编写布局，其外层为CoordinatorLayout，这里使用了预设behavior：appbar_scrolling_view_behavior，在监听的控件加上Flag设置，例如这里的app:layout_scrollFlags="scroll|enterAlways""
其Flag参数包括
scroll:将此布局和滚动时间关联。这个标识要设置在其他标识之前，没有这个标识则布局不会滚动且其他标识设置无效
enterAlways:任何向下滚动操作都会使此布局可见。这个标识通常被称为快速返回模式
enterAlwaysCollapsed：假设你定义了一个最小高度（minHeight）同时enterAlways也定义了，那么view将在到达这个最小高度的时候开始显示，并且从这个时候开始慢慢展开，当滚动到顶部的时候展开完
exitUntilCollapsed：当你定义了一个minHeight，此布局将在滚动到达这个最小高度的时候折叠
snap:当一个滚动事件结束，如果视图是部分可见的，那么它将被滚动到收缩或展开。例如，如果视图只有底部25%显示，它将折叠。相反，如果它的底部75%可见，那么它将完全展开
snap：

<?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"tools:context=".MainActivity"><android.support.v7.widget.RecyclerViewandroid:id="@+id/recycler_view"android:layout_width="match_parent"android:layout_height="match_parent"android:clipChildren="false"android:clipToPadding="false"app:layout_behavior="@string/appbar_scrolling_view_behavior" /><android.support.design.widget.AppBarLayoutandroid:layout_width="match_parent"android:layout_height="wrap_content"><android.support.v7.widget.Toolbarandroid:layout_width="match_parent"android:layout_height="?attr/actionBarSize"android:layout_gravity="center"android:background="?attr/colorPrimary"app:layout_scrollFlags="scroll|enterAlways"app:title="这是标题" /></android.support.design.widget.AppBarLayout></android.support.design.widget.CoordinatorLayout>

由于使用的是RecyclerView，故还需要适配器

public class MyAdapter extends RecyclerView.Adapter<MyAdapter.MyViewHolder> {private List<String> list;class MyViewHolder extends RecyclerView.ViewHolder {private TextView textView;public MyViewHolder(View itemView) {super(itemView);textView = (TextView) itemView.findViewById(android.R.id.text1);}}public MyAdapter(List<String> list) {this.list = list;}@Overridepublic MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {LayoutInflater layoutInflater = LayoutInflater.from(parent.getContext());View view = layoutInflater.inflate(android.R.layout.simple_list_item_1,parent,false);MyViewHolder holder = new MyViewHolder(view);return holder;}@Overridepublic void onBindViewHolder(MyViewHolder holder, int position) {holder.textView.setText(list.get(position));}@Overridepublic int getItemCount() {return list.size();}
}

设置RecyclerView数据

public class MainActivity extends AppCompatActivity {private List<String> list = new ArrayList<>();private MyAdapter adapter;private RecyclerView recyclerView;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);recyclerView = (RecyclerView) findViewById(R.id.recycler_view);recyclerView.setLayoutManager(new LinearLayoutManager(this));for (int i = 0; i < 30; i++) {list.add("item " + i);}adapter = new MyAdapter(list);recyclerView.setAdapter(adapter);}
}

查看效果如下

ViewPager + TabLayout + Fragment + AppBarLayout

AppBarLayout同时还可以使用其他可滑动控件，例如NestedScrollView，其常用组合为：ViewPager + TabLayout + Fragment + AppBarLayout
由于这套组合的体验效果不错，这里展现一下这个样式的demo
首先依旧是引入依赖

因为使用了Toolbar，所以这里使用NoActionBar的主题

<resources><!-- Base application theme. --><style name="AppTheme" parent="Theme.AppCompat.Light.NoActionBar"><!-- Customize your theme here. --><item name="colorPrimary">@color/colorPrimary</item><item name="colorPrimaryDark">@color/colorPrimaryDark</item><item name="colorAccent">@color/colorAccent</item></style></resources>

编写ViewPager的Fragment布局，这里简单显示text，记得这里应该是一个滑动控件

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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:orientation="vertical"><android.support.v4.widget.NestedScrollViewandroid:layout_width="match_parent"android:layout_height="match_parent"app:layout_behavior="@string/appbar_scrolling_view_behavior"><TextViewandroid:id="@+id/text_view"android:layout_width="match_parent"android:layout_height="match_parent"android:textColor="@android:color/black"android:textSize="24sp" /></android.support.v4.widget.NestedScrollView>
</LinearLayout>

然后是自定义的fragment

public class DefaultFragment extends Fragment {@Nullable@Overridepublic View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {View view = inflater.inflate(R.layout.fragment_layout,container,false);TextView textView = (TextView) view.findViewById(R.id.text_view);Bundle bundle = getArguments();String title = bundle.getString("title");textView.setText(title+"\n\n");for (int i = 0; i < 10; i++) {textView.append("这是一个ViewPager + TabLayout + Fragment + AppBarLayout测试用例\n\n");}return view;}
}

接下来是主布局

<?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:orientation="vertical"tools:context=".MainActivity"><android.support.design.widget.AppBarLayoutandroid:layout_width="match_parent"android:layout_height="wrap_content"><android.support.v7.widget.Toolbarandroid:layout_width="match_parent"android:layout_height="?attr/actionBarSize"android:background="?attr/colorPrimary"app:layout_scrollFlags="scroll|enterAlways"app:title="标题" /><android.support.design.widget.TabLayoutandroid:id="@+id/table_layout"android:layout_width="match_parent"android:layout_height="wrap_content"android:background="@android:color/holo_orange_light"app:tabGravity="fill"app:tabMode="scrollable" /></android.support.design.widget.AppBarLayout><android.support.v4.view.ViewPagerandroid:id="@+id/view_pager"android:layout_width="match_parent"android:layout_height="match_parent"app:layout_behavior="@string/appbar_scrolling_view_behavior" /></android.support.design.widget.CoordinatorLayout>

最后关联TableLayout和ViewPager

public class MainActivity extends AppCompatActivity {private TabLayout tabLayout;private ViewPager viewPager;private String[] title = {"新闻", "体育", "汽车", "科技", "手机", "数码", "读书", "艺术"};@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);tabLayout = (TabLayout) findViewById(R.id.table_layout);viewPager = (ViewPager) findViewById(R.id.view_pager);MyPagerAdapter adapter = new MyPagerAdapter(getSupportFragmentManager());viewPager.setAdapter(adapter);tabLayout.setupWithViewPager(viewPager);}class MyPagerAdapter extends FragmentPagerAdapter {public MyPagerAdapter(FragmentManager fm) {super(fm);}@Overridepublic CharSequence getPageTitle(int position) {return title[position];}@Overridepublic Fragment getItem(int position) {Fragment fragment = new DefaultFragment();Bundle bundle = new Bundle();bundle.putString("title", title[position]);fragment.setArguments(bundle);return fragment;}@Overridepublic int getCount() {return title.length;}}
}

这样就完成了显示功能

CollapsingToolbarLayout

这个控件可以实现Toolbar的折叠效果
先看下其常用参数
expandedTitleMargin：展开后的边距
statusBarScrim：状态栏颜色
contentScrim：内容颜色
app:layout_collapseMode：设置折叠模式，分为视差模式(parallax:在折叠的时候会有折叠视差效果，一般搭配layout_collapseParallaxMultiplier，视差的明显程度)，固定模式(pin：在折叠的时候最后固定在顶端，再和toolbar一起推出)，无模式(none：折叠时toolbar直接推出)
expandedTitleGravity：展开的位置
collapsedTitleGravity：折叠的位置
使用时依然需要导入依赖

implementation 'com.android.support:design:25.4.0'

然后使用NoActionBar主题
使用时的布局示例

<?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"tools:context=".MainActivity"><android.support.v4.widget.NestedScrollViewandroid:layout_width="match_parent"android:layout_height="match_parent"app:layout_behavior="@string/appbar_scrolling_view_behavior"><TextViewandroid:id="@+id/text_view"android:layout_width="match_parent"android:layout_height="match_parent"android:text="@string/test_text"android:textColor="@android:color/black"android:textSize="24sp" /></android.support.v4.widget.NestedScrollView><android.support.design.widget.AppBarLayoutandroid:layout_width="match_parent"android:layout_height="180dp"><android.support.design.widget.CollapsingToolbarLayoutandroid:layout_width="match_parent"android:layout_height="match_parent"app:layout_scrollFlags="scroll|exitUntilCollapsed"app:expandedTitleMargin="8dp"app:statusBarScrim="?attr/colorPrimary"app:contentScrim="?attr/colorPrimary"app:expandedTitleGravity="center"app:collapsedTitleGravity="center"app:title="现代诗歌欣赏"><ImageViewandroid:layout_width="match_parent"android:layout_height="match_parent"android:scaleType="centerCrop"android:src="@drawable/tdj"app:layout_collapseMode="parallax"app:layout_collapseParallaxMultiplier="0.5"/><android.support.v7.widget.Toolbarapp:layout_collapseMode="pin"android:id="@+id/tool_bar"android:layout_width="match_parent"android:layout_height="?attr/actionBarSize"android:background="?attr/colorPrimary"/></android.support.design.widget.CollapsingToolbarLayout></android.support.design.widget.AppBarLayout></android.support.design.widget.CoordinatorLayout>

设置Toolbar

public class MainActivity extends AppCompatActivity {private Toolbar toolbar;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);toolbar = (Toolbar) findViewById(R.id.tool_bar);toolbar.setNavigationIcon(R.mipmap.ic_launcher);setSupportActionBar(toolbar);}
}

实现的效果如下图

转载于:https://www.cnblogs.com/cj5785/p/10664597.html