Question

我正在尝试创建一个包含按钮的应用程序。如果按下该按钮，将播放名为Test.mp3的歌曲。我将具有确切名称和文件类型的歌曲复制到目录中，但它始终显示找不到该文件。我尝试了很多东西，包括将歌曲复制到不同的目录，以及更改目录，但没有运气。这就是我现在所拥有的：

package com.example.lenovo.myapplication69;
import android.content.Intent;
import android.media.AudioManager;
import android.media.MediaPlayer;
import android.net.Uri;
import android.os.Environment;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;
import java.io.File;
import java.io.IOException;

public class MainActivity extends AppCompatActivity {

Button bt;
MediaPlayer mediaPlayer;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    bt = (Button) findViewById(R.id.button);
    bt.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
        mediaPlayer = new MediaPlayer();
        mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
        File f = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_MUSIC),"Test.mp3");
        String media_path = String.valueOf(f);
        Toast.makeText(getApplicationContext(),media_path,Toast.LENGTH_LONG).show();
        Uri uri  = Uri.parse(media_path);
            try {

                mediaPlayer.setDataSource(getApplicationContext(),uri);
                mediaPlayer.prepare();
                mediaPlayer.start();
                Toast.makeText(getApplicationContext(),"Playback started",Toast.LENGTH_LONG).show();
                bt.setEnabled(false);
            } catch (IOException e) {
                Toast.makeText(getApplicationContext(),"error ",Toast.LENGTH_LONG).show();
                    e.printStackTrace();
            }
            mediaPlayer.setOnCompletionListener(new MediaPlayer.OnCompletionListener() {
                @Override
                public void onCompletion(MediaPlayer mp) {
                    bt.setEnabled(true);
                    mediaPlayer.release();
                    mediaPlayer = null;
                    Toast.makeText(getApplicationContext(),"Playback finished", Toast.LENGTH_LONG).show();
                }
            });
        }
    });
}

    }

这是我在Android清单中的内容。是的，我知道很多无用的权限，但无论如何。

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.lenovo.myapplication69">
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.BLUETOOTH"/>
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN"/>
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.WRITE_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.READ"/>
<uses-permission android:name="android.permission.MANAGE_DOCUMENTS"/>
<uses-permission android:name="android.permission.MEDIA_CONTENT_CONTROL"/>
<uses-permission android:name="android.permission.READ_PHONE_STATE"/>

<application

    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:roundIcon="@mipmap/ic_launcher_round"
    android:supportsRtl="true"
    android:theme="@style/AppTheme">

    <activity android:name=".MainActivity">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>

</application>

</manifest>

androidstudio媒体播放器无法找到我的文件

0 个答案: