Material Design - 常用控制元件介紹和使用

新增依賴

 implementation 'com.github.bumptech.glide:glide:3.7.0'
implementation 'com.android.support:cardview-v7:27.1.1'
 implementation 'com.android.support:recyclerview-v7:27.1.1'
 implementation 'com.android.support:design:27.1.1'

activity_main主佈局

<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.DrawerLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/drawer_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <android.support.design.widget.CoordinatorLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <android.support.design.widget.AppBarLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content">

            <android.support.v7.widget.Toolbar
                android:id="@+id/toolbar"
                android:layout_width="match_parent"
                android:layout_height="?attr/actionBarSize"
                android:background="?attr/colorPrimary"
                app:title="@string/app_name"
                android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"
                app:popupTheme="@style/ThemeOverlay.AppCompat.Light"
                app:layout_scrollFlags="scroll|enterAlways|snap" />
        </android.support.design.widget.AppBarLayout>

        <android.support.v4.widget.SwipeRefreshLayout
            android:id="@+id/swipe_refresh"
            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/recycler_view"
                android:layout_width="match_parent"
                android:layout_height="match_parent" />
        </android.support.v4.widget.SwipeRefreshLayout>

        <android.support.design.widget.FloatingActionButton
            android:id="@+id/fab"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="bottom|end"
            android:layout_margin="16dp"
            android:src="@drawable/ic_done" />
    </android.support.design.widget.CoordinatorLayout>

    <android.support.design.widget.NavigationView
        android:id="@+id/nav_view"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_gravity="start"
        app:headerLayout="@layout/nav_header"
        app:menu="@menu/nav_menu" />

</android.support.v4.widget.DrawerLayout>

DrawerLayout+NavigationView實現側滑
mDrawerLayout.openDrawer(GravityCompat.START);開啟
mDrawerLayout.openDrawer(Gravity.LEFT)左邊

AppBarLayout
app:layout_scrollFlags引數:

• scroll值設為scroll的View會跟隨滾動事件一起發生移動。
• enterAlways:值設為enterAlways的View,當ScrollView往下滾動時，該View會直接往下滾動。而不用考慮ScrollView是否在滾動。
• exitUntilCollapsed：值設為exitUntilCollapsed的View，當這個View要往上逐漸“消逝”時，會一直往上滑動，直到剩下的的高度達到它的最小高度後，再響應ScrollView的內部滑動事件。
• enterAlwaysCollapsed：是enterAlways的附加選項，一般跟enterAlways一起使用，它是指，View在往下“出現”的時候，首先是enterAlways效果，當View的高度達到最小高度時，View就暫時不去往下滾動，直到ScrollView滑動到頂部不再滑動時，View再繼續往下滑動，直到滑到View的頂部結束。

NavigationView\

 android:layout_gravity="start"側滑在左邊,end代表在右邊
  app:headerLayout="@layout/nav_header"頭部的佈局
 app:menu="@menu/nav_menu"子選單的內容

nav_header佈局

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="180dp"
    android:background="?attr/colorPrimary"
    android:padding="10dp">

    <ImageView
        android:id="@+id/icon_image"
        android:layout_width="70dp"
        android:layout_height="70dp"
        android:layout_centerInParent="true"
        android:src="@drawable/nav_icon" />

    <TextView
        android:id="@+id/mail"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:text="peakmain@mail.com"
        android:textColor="#FFF"
        android:textSize="14sp" />

    <TextView
        android:id="@+id/username"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_above="@id/mail"
        android:text="Peakmain"
        android:textColor="#FFF"
        android:textSize="14sp" />

</RelativeLayout>

nav_menu選單內容

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android">
    <group android:checkableBehavior="single">
        <item
            android:id="@+id/nav_call"
            android:icon="@drawable/nav_call"
            android:title="Call" />
        <item
            android:id="@+id/nav_friends"
            android:icon="@drawable/nav_friends"
            android:title="Friends" />
        <item
            android:id="@+id/nav_location"
            android:icon="@drawable/nav_location"
            android:title="Location" />
        <item
            android:id="@+id/nav_mail"
            android:icon="@drawable/nav_mail"
            android:title="Mail" />
        <item
            android:id="@+id/nav_task"
            android:icon="@drawable/nav_task"
            android:title="Tasks" />
    </group>
</menu>

toolbar樣式

<?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">
    <item
    android:id="@+id/backup"
    android:icon="@drawable/ic_backup"
    android:title="Backup"
    app:showAsAction="always"/>
    <item
        android:id="@+id/delete"
        android:icon="@drawable/ic_delete"
        android:title="Delete"
        app:showAsAction="ifRoom"/>
    <item
        android:id="@+id/settings"
        android:icon="@drawable/ic_settings"
        android:title="Settings"
        app:showAsAction="never"/>
</menu>

1.alaways:這個值會使選單項一直顯示在ActionBar上。
2.ifRoom:如果有足夠的空間,這個值會使選單顯示在ActionBar上。
3.never:這個值選單永遠不會出現在ActionBar是。
4.withText:這個值使選單和它的圖示，選單文字一起顯示。

MainActivity主佈局

public class MainActivity extends AppCompatActivity {
    private DrawerLayout mDrawerLayout;
    /**
     * 初始化資料
     */
    private Fruit[] fruits = {new Fruit("Apple", R.drawable.apple), new Fruit("Banana", R.drawable.banana),
            new Fruit("Orange", R.drawable.orange), new Fruit("Watermelon", R.drawable.watermelon),
            new Fruit("Pear", R.drawable.pear), new Fruit("Grape", R.drawable.grape),
            new Fruit("Pineapple", R.drawable.pineapple), new Fruit("Strawberry", R.drawable.strawberry),
            new Fruit("Cherry", R.drawable.cherry), new Fruit("Mango", R.drawable.mango)};
    private List<Fruit> fruitList = new ArrayList<>();
    private SwipeRefreshLayout swipeRefresh;
    private FruitAdapter adapter;

    @RequiresApi(api = Build.VERSION_CODES.JELLY_BEAN_MR2)
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        //設定toolbar
        Toolbar toolbar = findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);
        //側滑
        NavigationView navView = findViewById(R.id.nav_view);
        mDrawerLayout = findViewById(R.id.drawer_layout);
        ActionBar actionBar = getSupportActionBar();
        if (actionBar != null) {
            //設定導航預設是箭頭，id是android.R.id.home
            actionBar.setDisplayHomeAsUpEnabled(true);
            //將箭頭設定成我們的圖片
            actionBar.setHomeAsUpIndicator(R.drawable.ic_menu);
        }
        //設定被選中的item
        navView.setCheckedItem(R.id.nav_call);
        //獲取側滑的頭部
        View headerView = navView.getHeaderView(0);
        //頭部的影象
        headerView.findViewById(R.id.icon_image).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Toast.makeText(MainActivity.this, "點選了影象", Toast.LENGTH_SHORT).show();
            }
        });
        //頭部的郵件
        headerView.findViewById(R.id.mail).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Toast.makeText(MainActivity.this, "點選了郵件", Toast.LENGTH_SHORT).show();
            }
        });
        //頭部的使用者名稱
        headerView.findViewById(R.id.username).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Toast.makeText(MainActivity.this, "點選了使用者名稱", Toast.LENGTH_SHORT).show();
            }
        });

        //側滑點選列表
        navView.setNavigationItemSelectedListener(new NavigationView.OnNavigationItemSelectedListener() {
            @Override
            public boolean onNavigationItemSelected(@NonNull MenuItem item) {
                Toast.makeText(MainActivity.this, item.getTitle(), Toast.LENGTH_SHORT).show();
                //關閉側滑
                mDrawerLayout.closeDrawers();
                return true;
            }
        });
        //懸浮點選事件
        FloatingActionButton fab = findViewById(R.id.fab);
        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // Snackbar的使用，第一個引數代表附屬於哪個View,第二個文字
                Snackbar.make(v, "Data deleted", Snackbar.LENGTH_LONG).setAction("Undo", new View.OnClickListener() {
                    @Override
                    public void onClick(View v) {
                        Toast.makeText(MainActivity.this, "Data restored", Toast.LENGTH_SHORT).show();
                    }
                }).show();
            }
        });
        initFruits();
        RecyclerView recyclerView = findViewById(R.id.recycler_view);
        GridLayoutManager layoutManager = new GridLayoutManager(this, 2);
        recyclerView.setLayoutManager(layoutManager);
        adapter = new FruitAdapter(fruitList);
        recyclerView.setAdapter(adapter);
        //下拉重新整理的使用
        swipeRefresh = findViewById(R.id.swipe_refresh);
        //設定下拉重新整理時候的箭頭的顏色
        swipeRefresh.setColorSchemeResources(R.color.colorAccent);
        //下拉重新整理的事件
        swipeRefresh.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
            @Override
            public void onRefresh() {
                refreshFruits();
            }
        });
    }

    /**
     * 重新整理資料,模擬資料
     */
    private void refreshFruits() {
        new Thread(new Runnable() {
            @Override
            public void run() {
                try {
                    Thread.sleep(2000);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
                runOnUiThread(new Runnable() {
                    @Override
                    public void run() {
                        initFruits();
                        adapter.notifyDataSetChanged();
                        swipeRefresh.setRefreshing(false);
                    }
                });
            }
        }).start();
    }

    /**
     * 初始化資料
     */
    private void initFruits() {
        fruitList.clear();
        for (int i = 0; i < 50; i++) {
            Random random = new Random();
            int index = random.nextInt(fruits.length);
            fruitList.add(fruits[index]);
        }
    }

    /**
     * 載入建立 menu 佈局
     *
     * @param menu
     * @return
     */
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.toolbar, menu);
        return true;
    }

    /**
     * 點選menu的一些回掉
     *
     * @param item
     * @return
     */
    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
            case android.R.id.home:
                mDrawerLayout.openDrawer(GravityCompat.START);
                break;
            case R.id.backup:
                Toast.makeText(this, "You clicked Backup", Toast.LENGTH_SHORT).show();
                break;
            case R.id.delete:
                Toast.makeText(this, "You clicked Delete", Toast.LENGTH_SHORT).show();
                break;
            case R.id.settings:
                Toast.makeText(this, "You clicked Settings", Toast.LENGTH_SHORT).show();
                break;
            default:
                break;
        }
        return super.onOptionsItemSelected(item);
    }
}

FruitAdapter介面卡

public class FruitAdapter extends RecyclerView.Adapter<FruitAdapter.ViewHolder> {
    private static final String TAG = "FruitAdapter";

    private Context mContext;

    private List<Fruit> mFruitList;

    public FruitAdapter(List<Fruit> fruitList) {
        this.mFruitList = fruitList;
    }

    public class ViewHolder extends RecyclerView.ViewHolder {
        CardView cardView;
        ImageView fruitImage;
        TextView fruitName;

        public ViewHolder(View itemView) {
            super(itemView);
            cardView = (CardView) itemView;
            fruitImage = itemView.findViewById(R.id.fruit_image);
            fruitName = itemView.findViewById(R.id.fruit_name);
        }
    }

    @NonNull
    @Override
    public ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        //獲得上下文
        if (mContext == null) {
            mContext = parent.getContext();
        }
        View view = LayoutInflater.from(mContext).inflate(R.layout.fruit_item, parent, false);
        final ViewHolder holder = new ViewHolder(view);
        holder.cardView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                //獲取當前的位置
                int position = holder.getAdapterPosition();
                Fruit fruit = mFruitList.get(position);
                Intent intent = new Intent(mContext, FruitActivity.class);
                intent.putExtra(FruitActivity.FRUIT_NAME, fruit.getName());
                intent.putExtra(FruitActivity.FRUIT_IMAGE_ID, fruit.getImageId());
                mContext.startActivity(intent);
            }
        });
        return holder;
    }

    /**
     * 設定資料
     */
    @Override
    public void onBindViewHolder(@NonNull ViewHolder holder, int position) {
        Fruit fruit = mFruitList.get(position);
        //設定圖片
        Glide.with(mContext).load(fruit.getImageId()).into(holder.fruitImage);
        //設定名字
        holder.fruitName.setText(fruit.getName());
    }

    @Override
    public int getItemCount() {
        return mFruitList.size();
    }
}

FruitActivity

public class FruitActivity extends AppCompatActivity {
    public static final String FRUIT_NAME = "FRUIT_NAME";
    public static final String FRUIT_IMAGE_ID = "FRUIT_IMAGE_ID";

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_fruit);
        //獲取傳過來的名字和圖片的Id
        Intent intent = getIntent();
        String fruitName = intent.getStringExtra(FRUIT_NAME);
        int fruitImageId = intent.getIntExtra(FRUIT_IMAGE_ID, 0);
        //toolbar
        Toolbar toolbar = findViewById(R.id.toolbar);
        //collapsingToolbar
        CollapsingToolbarLayout collapsingToolbar = findViewById(R.id.collapsing_toolbar);
        ImageView fruitImageView = findViewById(R.id.fruit_image_view);
        TextView fruitContentText = findViewById(R.id.fruit_content_text);
        //設定actionbar
        setSupportActionBar(toolbar);
        ActionBar actionBar = getSupportActionBar();
        if (actionBar != null) {
            actionBar.setDisplayHomeAsUpEnabled(true);
        }
        //設定標題
        collapsingToolbar.setTitle(fruitName);
        //載入圖片
        Glide.with(this).load(fruitImageId).into(fruitImageView);
        String fruitContent = generateFruitContent(fruitName);
        fruitContentText.setText(fruitContent);
    }

    private String generateFruitContent(String fruitName) {
        StringBuilder fruitContent = new StringBuilder();
        for (int i = 0; i < 500; i++) {
            fruitContent.append(fruitName);
        }
        return fruitContent.toString();
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
            case android.R.id.home:
                finish();
                return true;
            default:
                break;
        }
        return super.onOptionsItemSelected(item);
    }
}

activity_fruit佈局

<?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"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true">

    <android.support.design.widget.AppBarLayout
        android:id="@+id/appBar"
        android:layout_width="match_parent"
        android:layout_height="250dp"
        android:fitsSystemWindows="true">

        <android.support.design.widget.CollapsingToolbarLayout
            android:id="@+id/collapsing_toolbar"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:fitsSystemWindows="true"
            android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"
            app:contentScrim="?attr/colorPrimary"
            app:layout_scrollFlags="scroll|exitUntilCollapsed">

            <ImageView
                android:id="@+id/fruit_image_view"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:fitsSystemWindows="true"
                android:scaleType="centerCrop"
                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" />
        </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">

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="vertical">

            <android.support.v7.widget.CardView
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:layout_marginBottom="15dp"
                android:layout_marginLeft="15dp"
                android:layout_marginRight="15dp"
                android:layout_marginTop="35dp"
                app:cardCornerRadius="4dp">

                <TextView
                    android:id="@+id/fruit_content_text"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:layout_margin="10dp" />
            </android.support.v7.widget.CardView>
        </LinearLayout>
    </android.support.v4.widget.NestedScrollView>

    <android.support.design.widget.FloatingActionButton
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_margin="16dp"
        android:src="@drawable/ic_comment"
        app:layout_anchor="@id/appBar"
        app:layout_anchorGravity="bottom|end" />
</android.support.design.widget.CoordinatorLayout>

fitsSystemWindows只作用在sdk>=19的系統上就是高於4.4的系統
這個屬性可以給任何view設定,只要設定了這個屬性此view的所有padding屬性失效.
只有在設定了透明狀態列(StatusBar)或者導航欄(NavigationBar)此屬性才會生效

CollapsingToolbarLayout
CollapsingToolbarLayout是用來對Toolbar進行再次包裝的ViewGroup，主要是用於實現摺疊（其實就是看起來像伸縮~）的App Bar效果。它需要放在AppBarLayout佈局裡面，並且作為AppBarLayout的直接子View。CollapsingToolbarLayout主要包括幾個功能

• 內容紗布：根據滾動的位置是否到達一個閥值，來決定是否對View“蓋上紗布”。可以通過setContentScrim(Drawable)來設定紗布的圖片.如我們這裡的app:contentScrim="?attr/colorPrimary"
• app:layout_collapseMode="pin":將子View位置固定(Pinned position children)：子View可以選擇是否在全域性空間上固定位置，這對於Toolbar來說非常有用，因為當佈局在移動時，可以將Toolbar固定位置而不受移動的影響。
• app:layout_collapseMode="parallax" 視差滾動子View(Parallax scrolling children):子View可以選擇在當前的佈局當時是否以“視差”的方式來跟隨滾動。（PS:其實就是讓這個View的滾動的速度比其他正常滾動的View速度稍微慢一點）
• app:layout_behavior="@string/appbar_scrolling_view_behavior"設定放置到狀態列下面
• app:layout_anchor="@id/appBar"附屬在toolbar上面