Java 如何在布局活动中显示随机声音结果的值,以便播放
我在原始android studio文件夹中有3个音频: 声音1.mp3 Sound2.mp3 Sound3.mp3 然后,我想使用fisher-yates洗牌算法进行音频洗牌。 下面的代码正确吗?或者我需要先初始化它吗Java 如何在布局活动中显示随机声音结果的值,以便播放,java,android,android-mediaplayer,android-imageview,Java,Android,Android Mediaplayer,Android Imageview,我在原始android studio文件夹中有3个音频: 声音1.mp3 Sound2.mp3 Sound3.mp3 然后,我想使用fisher-yates洗牌算法进行音频洗牌。 下面的代码正确吗?或者我需要先初始化它吗 / package com.example.once; import androidx.appcompat.app.AppCompatActivity; import android.content.Intent; import android.media.MediaPla
/ package com.example.once;
import androidx.appcompat.app.AppCompatActivity;
import android.content.Intent;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.view.View;
import android.widget.TextView;
import java.util.Random;
import java.util.Arrays;
public class Main4Activity extends AppCompatActivity {
// Java Program to shuffle a given array
public static class ShuffleRand {
// A Function to generate a random permutation of arr []
static void randomize (String arr [], int n) {
// Creating a object for Random class
Random r = new Random ();
// Start from the last element and swap one by one. We don't
// need to run for the first element that's why i> 0
for (int i = n - 1; i> 0; i--) {
// Pick a random index from 0 to i
int j = r.nextInt (i + 1);
// Swap arr [i] with the element at random index
String temp = arr [i];
arr [i] = arr [j];
arr [j] = temp;
}
// Prints the random array
System.out.println (arr [0]);
System.out.println (Arrays.toString (arr));
}
// Driver Program to test above function
public static void main (String [] args) {
String [] arr = {"R.raw.sound1, R.raw.sound2, R.raw.sound3"};
int n = arr.length;
randomize (arr, n);
}
}
}
在获得随机值(arr[0])后,我想用onClick PlaySong在play按钮的.xml活动布局中输入值(arr[0])。怎么做
<ImageView
android: id = "@ + id / imageView5"
android: layout_width = "75dp"
android: layout_height = "80dp"
android: onClick = "playSong"
android: layout_marginTop = "50dp"
app: layout_constraintEnd_toEndOf = "parent"
app: layout_constraintStart_toStartOf = "parent"
app: layout_constraintTop_toBottomOf = "@ + id / imageView8"
app: srcCompat = "@ drawable / play" />
您可以这样做:
private MediaPlayer mMediaPlayer;
public void stopSong() {
if (mMediaPlayer != null) {
mMediaPlayer.release();
mMediaPlayer = null;
}
}
public void playSong(Context c, int rid) {
stop();
mMediaPlayer = MediaPlayer.create(c, rid);
mMediaPlayer.setOnCompletionListener(new MediaPlayer.OnCompletionListener() {
@Override
public void onCompletion(MediaPlayer mediaPlayer) {
stop();
}
});
mMediaPlayer.start();
}
因此,您可以调用此函数:
playSong(this, getResources().getIdentifier(arr[0], "raw", getPackageName());
您可以这样做:
private MediaPlayer mMediaPlayer;
public void stopSong() {
if (mMediaPlayer != null) {
mMediaPlayer.release();
mMediaPlayer = null;
}
}
public void playSong(Context c, int rid) {
stop();
mMediaPlayer = MediaPlayer.create(c, rid);
mMediaPlayer.setOnCompletionListener(new MediaPlayer.OnCompletionListener() {
@Override
public void onCompletion(MediaPlayer mediaPlayer) {
stop();
}
});
mMediaPlayer.start();
}
因此,您可以调用此函数:
playSong(this, getResources().getIdentifier(arr[0], "raw", getPackageName());
谢谢你的回答。但是,im实现你的代码,在变量arr中的第109行有错误。你能帮助我吗?然后在活动主界面上,我不能调用函数playSong[谢谢你的回答。但是,im实现你的代码,在变量arr中的第109行有错误。你能帮助我吗?然后在活动主界面上,我不能调用函数playSong[