目標(biāo)：實現(xiàn)各APP中的底部導(dǎo)航菜單功能熏版。
前提：AndroidStudio + 安卓基礎(chǔ)知識
操作：
-
1吴菠，在AS中如下操作
按照123操作進行 -
2,繼續(xù)操作
輸入名稱奥此，點擊finish -
3，完成哪轿，自動生成
自動生成
操作很簡單蹂午，下面分析原理：
系統(tǒng)生成了3個文件：
- 1 bottom_nav_menu.xml
<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android">
<item
android:id="@+id/navigation_home"
android:icon="@drawable/ic_home_black_24dp"
android:title="@string/title_home" />
<item
android:id="@+id/navigation_dashboard"
android:icon="@drawable/ic_dashboard_black_24dp"
android:title="@string/title_dashboard" />
<item
android:id="@+id/navigation_notifications"
android:icon="@drawable/ic_notifications_black_24dp"
android:title="@string/title_notifications" />
</menu>
該文件創(chuàng)建了一個菜單栏豺，用于展示。
- 2 activity_bottom.xml
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout 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:id="@+id/container"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".BottomActivity">
<TextView
android:id="@+id/message"
android:layout_width="wrap_content"
android:layout_height="26dp"
android:layout_marginLeft="184dp"
android:layout_marginTop="172dp"
android:text="@string/title_home"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<android.support.design.widget.BottomNavigationView
android:id="@+id/nav_view"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:background="?android:attr/windowBackground"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="1.0"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:menu="@menu/bottom_nav_menu" />
</android.support.constraint.ConstraintLayout>
其中BottomNavigationView組件定義了導(dǎo)航模塊豆胸。
- 3 BottomActivity
package com.example.myapplication2;
import android.os.Bundle;
import android.support.design.widget.BottomNavigationView;
import android.support.v7.app.AppCompatActivity;
import android.support.annotation.NonNull;
import android.view.MenuItem;
import android.widget.TextView;
public class BottomActivity extends AppCompatActivity {
private TextView mTextMessage;
private BottomNavigationView.OnNavigationItemSelectedListener mOnNavigationItemSelectedListener
= new BottomNavigationView.OnNavigationItemSelectedListener() {
@Override
public boolean onNavigationItemSelected(@NonNull MenuItem item) {
switch (item.getItemId()) {
case R.id.navigation_home:
mTextMessage.setText(R.string.title_home);
return true;
case R.id.navigation_dashboard:
mTextMessage.setText(R.string.title_dashboard);
return true;
case R.id.navigation_notifications:
mTextMessage.setText(R.string.title_notifications);
return true;
}
return false;
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_bottom);
BottomNavigationView navView = findViewById(R.id.nav_view);
mTextMessage = findViewById(R.id.message);
navView.setOnNavigationItemSelectedListener(mOnNavigationItemSelectedListener);
}
}
該文件定義了導(dǎo)航組建的初始化和點擊事件奥洼。
