效果图
Screenshot_20180102-154959.png
首先BottomNavigationView的使用是需要添加依赖包的
implementation 'com.android.support:design:26.1.0'
1536659064(1).jpg
app:itemBackground="@color/colorPrimaryDark" --背景颜色
app:itemIconTint="@color/colorAccent" --图标颜色
app:itemTextColor="@color/colorAccent" --字体颜色
图标和按钮的颜色可以使用selector
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_checked="true" android:color="@color/colorAccent"></item>
<item android:color="@color/colorPrimary"></item>
</selector>
或者代码：
navigation.itemIconTintList = resources.getColorStateList(R.drawable.text_color, null);
navigation.itemTextColor = resources.getColorStateList(R.drawable.text_color, null);
布局main.xml文件
<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="android.my.com.myandroid.MainActivity"
android:orientation="vertical">
<FrameLayout
android:id="@+id/framelayout_main"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
app:layout_constraintBottom_toTopOf="@id/bottom_nav" />
<!--底部导航栏高度默认是 56dp-->
<android.support.design.widget.BottomNavigationView
android:id="@+id/bottom_nav"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:overScrollMode="never"
android:scrollbars="none"
app:itemBackground="@color/colorPrimaryDark"
app:itemIconTint="@color/colorAccent"
app:itemTextColor="@color/colorAccent"
app:menu="@menu/navigation">
</android.support.design.widget.BottomNavigationView>
</LinearLayout>
按钮布局在menu下navigation.xml
<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android">
<item
android:id="@+id/navigation_1"
android:icon="@drawable/ic_home_black_24dp"
android:title="第一个" />
<item
android:id="@+id/navigation_2"
android:icon="@drawable/ic_dashboard_black_24dp"
android:title="第二个" />
<item
android:id="@+id/navigation_3"
android:icon="@drawable/ic_notifications_black_24dp"
android:title="第三个" />
<item
android:id="@+id/navigation_4"
android:icon="@drawable/ic_notifications_black_24dp"
android:title="第四个" />
<item
android:id="@+id/navigation_5"
android:icon="@drawable/ic_notifications_black_24dp"
android:title="第五个" />
</menu>
通过mOnNavigationItemSelectedListener去监听按钮点击切换fragment
BottomNavigationView navigation;
private FragmentManager manager = getSupportFragmentManager();
FragmentTransaction transaction;
Fragment1 fragment1;
Fragment2 fragment2;
Fragment3 fragment3;
Fragment4 fragment4;
Fragment5 fragment5;
private BottomNavigationView.OnNavigationItemSelectedListener mOnNavigationItemSelectedListener
= new BottomNavigationView.OnNavigationItemSelectedListener() {
@Override
public boolean onNavigationItemSelected(@NonNull MenuItem item) {
switch (item.getItemId()) {
case R.id.navigation_1:
setMyFragment(1);
break;
case R.id.navigation_2:
setMyFragment(2);
break;
case R.id.navigation_3:
setMyFragment(3);
break;
case R.id.navigation_4:
setMyFragment(4);
break;
case R.id.navigation_5:
setMyFragment(5);
break;
}
// true 会显示这个Item被选中的效果 false 则不会
return true;
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
navigation = findViewById(R.id.bottom_nav);
navigation.setOnNavigationItemSelectedListener(mOnNavigationItemSelectedListener);
disableShiftMode(navigation);//去除动画
navigation.setSelectedItemId(navigation.getMenu().getItem(0).getItemId());//默认选择
setMyFragment(1);//默认选择
}
/**
* 将所有的Fragment都置为隐藏状态。
*
* @param transaction 用于对Fragment执行操作的事务
*/
private void hideFragments(FragmentTransaction transaction) {
if (fragment1 != null) {
transaction.hide(fragment1);
}
if (fragment2 != null) {
transaction.hide(fragment2);
}
if (fragment3 != null) {
transaction.hide(fragment3);
}
if (fragment4 != null) {
transaction.hide(fragment4);
}
if (fragment5 != null) {
transaction.hide(fragment5);
}
}
private void setMyFragment(int Index){
transaction = manager.beginTransaction();
hideFragments(transaction);
switch (Index){
case 1:
if (fragment1 == null) {
fragment1 = new Fragment1();
transaction.add(R.id.framelayout_main, fragment1);
} else {
transaction.show(fragment1);
}
break;
case 2:
if (fragment2 == null) {
fragment2 = new Fragment2();
transaction.add(R.id.framelayout_main, fragment2);
} else {
transaction.show(fragment2);
}
break;
case 3:
if (fragment3 == null) {
fragment3 = new Fragment3();
transaction.add(R.id.framelayout_main, fragment3);
} else {
transaction.show(fragment3);
}
break;
case 4:
if (fragment4 == null) {
fragment4 = new Fragment4();
transaction.add(R.id.framelayout_main, fragment4);
} else {
transaction.show(fragment4);
}
break;
case 5:
if (fragment5 == null) {
fragment5 = new Fragment5();
transaction.add(R.id.framelayout_main, fragment5);
} else {
transaction.show(fragment5);
}
break;
}
transaction.commit();
}
@SuppressLint("RestrictedApi")
public static void disableShiftMode(BottomNavigationView view) {
//获取子View BottomNavigationMenuView的对象
BottomNavigationMenuView menuView;
menuView = (BottomNavigationMenuView) view.getChildAt(0);
try {
//设置私有成员变量mShiftingMode可以修改
Field shiftingMode = menuView.getClass().getDeclaredField("mShiftingMode");
shiftingMode.setAccessible(true);
shiftingMode.setBoolean(menuView, false);
shiftingMode.setAccessible(false);
for (int i = 0; i < menuView.getChildCount(); i++) {
BottomNavigationItemView item = (BottomNavigationItemView) menuView.getChildAt(i);
//去除shift效果
item.setShiftingMode(false);
item.setChecked(item.getItemData().isChecked());
}
} catch (NoSuchFieldException e) {
Log.e("BNVHelper", "没有mShiftingMode这个成员变量", e);
} catch (IllegalAccessException e) {
Log.e("BNVHelper", "无法修改mShiftingMode的值", e);
}
}
需要注意的是按钮图标貌似不能使用png，只能使用xml。
最后我们可能还需要添加未读消息的角标
BottomNavigationMenuView menuView = (BottomNavigationMenuView) navigation.getChildAt(0);
//这里就是获取所添加的每一个Tab(或者叫menu)，
View tab = menuView.getChildAt(4);
BottomNavigationItemView itemView = (BottomNavigationItemView) tab;
//加载我们的角标View，新创建的一个布局
View badge = LayoutInflater.from(this).inflate(R.layout.message_number, menuView, false);
//添加到Tab上
itemView.addView(badge);
TextView count = badge.findViewById(R.id.tv_msg_count);
count.setText(String.valueOf(10));
//如果没有消息，不需要显示的时候那只需要将它隐藏即可
// count.setVisibility(View.GONE);
message_number.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="android.my.com.myandroid.MainActivity"
android:orientation="vertical">
<TextView
android:id="@+id/tv_msg_count"
android:layout_width="15dp"
android:layout_height="15dp"
android:layout_gravity="center"
android:layout_alignParentRight="true"
android:layout_marginRight="10dp"
android:layout_marginTop="3dp"
android:background="#f00"
android:gravity="center"
android:textColor="#fff"
android:textSize="6dp"/>
</RelativeLayout>
