安卓中的音频管理器，示例

<resources>
    <string name="app_name">GFG Ringtone Managerstring>
    <string name="vibrate_mode">vibrate_modestring>
    <string name="silent_mode">silent_modestring>
    <string name="ring_mode">ringtone_modestring>
    <string name="welcome_to_ringtone_manager_app">Welcome to Ringtone Manager Appstring>
    <string name="current_mode">Current Modestring>
resources>


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=".MainActivity">
    
    <TextView
        android:id="@+id/idTVHeading"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginLeft="20dp"
        android:layout_marginTop="50dp"
        android:layout_marginRight="20dp"
        android:text="@string/welcome_to_ringtone_manager_app"
        android:textAlignment="center"
        android:textColor="@color/green"
        android:textSize="20sp" />
    
    <TextView
        android:id="@+id/idTVCurrentMode"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/idTVHeading"
        android:layout_marginTop="60dp"
        android:text="@string/current_mode"
        android:textAlignment="center"
        android:textAllCaps="true"
        android:textColor="@color/black"
        android:textSize="20sp"
        android:textStyle="bold" />
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/idTVCurrentMode"
        android:layout_marginTop="80dp"
        android:orientation="horizontal"
        android:weightSum="3">
        
        
        
        <ImageButton
            android:id="@+id/idIBVibrateMode"
            android:layout_width="0dp"
            android:layout_height="100dp"
            android:layout_margin="10dp"
            android:layout_weight="1"
            android:background="@color/green"
            android:contentDescription="@string/vibrate_mode"
            android:src="@drawable/ic_vibrate"
            android:tint="@color/white" />
        <ImageButton
            android:id="@+id/idIBSilentMode"
            android:layout_width="0dp"
            android:layout_height="100dp"
            android:layout_margin="10dp"
            android:layout_weight="1"
            android:background="@color/green"
            android:contentDescription="@string/silent_mode"
            android:src="@drawable/ic_silent_mode"
            android:tint="@color/white" />
        <ImageButton
            android:id="@+id/idIBRingtoneMode"
            android:layout_width="0dp"
            android:layout_height="100dp"
            android:layout_margin="10dp"
            android:layout_weight="1"
            android:background="@color/green"
            android:contentDescription="@string/ring_mode"
            android:src="@drawable/ic_ringtone_mode"
            android:tint="@color/white" />
    LinearLayout>
RelativeLayout>


import android.app.NotificationManager;
import android.content.Context;
import android.content.Intent;
import android.media.AudioManager;
import android.os.Build;
import android.os.Bundle;
import android.view.View;
import android.widget.ImageButton;
import android.widget.TextView;
import android.widget.Toast;
import androidx.appcompat.app.AppCompatActivity;
public class MainActivity extends AppCompatActivity {
    // TextView to display the current ringer mode
    TextView currentStateTV;
    // Image buttons to switch ringer mode.
    ImageButton silentIB, vibrateIB, ringtoneIB;
    // object class variable for audio manager class.
    private AudioManager audioManager;
    // current mode to store integer value of ringer mode.
    int currentmode;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        currentStateTV = findViewById(R.id.idTVCurrentMode);
        silentIB = findViewById(R.id.idIBSilentMode);
        vibrateIB = findViewById(R.id.idIBVibrateMode);
        ringtoneIB = findViewById(R.id.idIBRingtoneMode);
        audioManager = (AudioManager) getSystemService(Context.AUDIO_SERVICE);
        // current mode will store current mode
        // of ringer of users device..
        currentmode = audioManager.getRingerMode();
        switch (currentmode) {
            case AudioManager.RINGER_MODE_NORMAL:
                currentStateTV.setText("Ringer Mode");
                break;
            case AudioManager.RINGER_MODE_SILENT:
                currentStateTV.setText("Silent Mode");
                break;
            case AudioManager.RINGER_MODE_VIBRATE:
                currentStateTV.setText("Vibrate Mode");
            default:
                currentStateTV.setText("Fail to get mode");
        }
        silentIB.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                NotificationManager notificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
                // the below code is to check the permission that the access
                // notification policy settings from users device..
                if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M && !notificationManager.isNotificationPolicyAccessGranted()) {
                    Intent intent = new Intent(android.provider.Settings.ACTION_NOTIFICATION_POLICY_ACCESS_SETTINGS);
                    startActivity(intent);
                }
                // set ringer mode here will sets your ringer mode to silent mode
                audioManager.setRingerMode(AudioManager.RINGER_MODE_SILENT);
                Toast.makeText(MainActivity.this, "Silent Mode Activated..", Toast.LENGTH_SHORT).show();
                currentStateTV.setText("Silent Mode Activated..");
            }
        });
        vibrateIB.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // set ringer mode here will sets your ringer mode to vibrate mode
                audioManager.setRingerMode(AudioManager.RINGER_MODE_VIBRATE);
                Toast.makeText(MainActivity.this, "Vibrate Mode Activated..", Toast.LENGTH_SHORT).show();
                currentStateTV.setText("Vibrate Mode Activated..");
            }
        });
        ringtoneIB.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // set ringer mode here will sets your ringer mode to normal mode
                audioManager.setRingerMode(AudioManager.RINGER_MODE_NORMAL);
                Toast.makeText(MainActivity.this, "Ringtone Mode Activated..", Toast.LENGTH_SHORT).show();
                currentStateTV.setText("Ringtone Mode Activated..");
            }
        });
    }
}