Android音乐播放器简单实现案例

package com.example.myapplication; import android.media.MediaPlayer; import android.net.Uri; import android.os.Build; import android.os.Bundle; import android.view.View; import android.widget.ImageButton; import android.widget.Toast; import androidx.annotation.RequiresApi; import androidx.appcompat.app.AppCompatActivity; import java.io.File; import java.io.IOException; /** * MediaPlay 实现简易的播放器 */ public class MainActivity extends AppCompatActivity { private MediaPlayer mediaPlayer;            //定义MediaPlayer对象 private boolean isPause = false;        //定义是否暂停 private File file; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); final ImageButton btn_play = (ImageButton) findViewById(R.id.btn_play); //获取“播放/暂停”按钮 final ImageButton btn_stop = (ImageButton) findViewById(R.id.btn_stop); //获取“停止”按钮 ; file = new File("/res/raw/bird.ogg"); if (file.exists()) { mediaPlayer = MediaPlayer.create(this, Uri.parse(file.getAbsolutePath())); } else { Toast.makeText(MainActivity.this, "要播放的音频文件不存在！", Toast.LENGTH_SHORT).show(); return; } // 为MediaPlayer 添加监听事件 完成事件监听器，当media.play.stop 后在重新play mediaPlayer.setOnCompletionListener(new MediaPlayer.OnCompletionListener() { @Override public void onCompletion(MediaPlayer mediaPlayer) { play(); } }); btn_play.setOnClickListener(new View.OnClickListener(){ @RequiresApi(api = Build.VERSION_CODES.LOLLIPOP) @Override public void onClick(View view) { if(mediaPlayer.isPlaying() && !isPause){ mediaPlayer.pause(); isPause = true; // 暂停播放 // 更好播放图标 ((ImageButton) view).setImageDrawable(getResources().getDrawable(R.drawable.play, null)); }else{ mediaPlayer.start();                           //继续播放 // 更换为暂停图标 ((ImageButton) view).setImageDrawable(getResources().getDrawable(R.drawable.pause, null)); isPause = false;                         //设置为播放状态 } } }); btn_stop.setOnClickListener(new View.OnClickListener() { //单击停止按钮，实现停止播放音频 @RequiresApi(api = Build.VERSION_CODES.LOLLIPOP) @Override public void onClick(View v) { mediaPlayer.stop();                    //停止播放 //更换为播放图标 btn_play.setImageDrawable(getResources().getDrawable(R.drawable.play, null)); } }); } private void play(){ // 重置MediaPlay mediaPlayer.reset(); try { mediaPlayer.setDataSource(file.getAbsolutePath()); mediaPlayer.prepare(); // 预加载 } catch (IOException e) { e.printStackTrace(); } } @Override protected void onDestroy() { if(mediaPlayer.isPlaying()){ mediaPlayer.stop(); } mediaPlayer.release(); super.onDestroy(); } }

package com.example.myapplication; import android.media.AudioAttributes; import android.media.SoundPool; import android.os.Bundle; import android.view.View; import android.widget.AdapterView; import android.widget.ListView; import androidx.appcompat.app.AppCompatActivity; import java.util.HashMap; public class MainActivity extends AppCompatActivity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); ListView listView = findViewById(R.id.listView); // 创建SoundPool 对象设置音频相关特性 //1.音频对象 AudioAttributes attr = new AudioAttributes.Builder()           //设置音效相关属性 .setUsage(AudioAttributes.USAGE_GAME)                 // 设置音效使用场景 .setContentType(AudioAttributes.CONTENT_TYPE_MUSIC)  // 设置音效的类型 .build(); final SoundPool soundpool = new SoundPool.Builder()           // 创建SoundPool对象 .setAudioAttributes(attr) // 设置音效池的属性 .setMaxStreams(10) // 设置最多可容纳10个音频流， .build(); // 要播放音频保存到HashMap中 final HashMap soundmap = new HashMap(); soundmap.put(0, soundpool.load(this, R.raw.cuckoo, 1)); soundmap.put(1, soundpool.load(this, R.raw.chimes, 1)); soundmap.put(2, soundpool.load(this, R.raw.notify, 1)); soundmap.put(3, soundpool.load(this, R.raw.ringout, 1)); soundmap.put(4, soundpool.load(this, R.raw.bird, 1)); soundmap.put(5, soundpool.load(this, R.raw.water, 1)); soundmap.put(6, soundpool.load(this, R.raw.cock, 1)); listView.setOnItemClickListener(new AdapterView.OnItemClickListener() { @Override public void onItemClick(AdapterView adapterView, View view, int i, long l) { soundpool.play(soundmap.get(i),1,1,0,0,1); } }); } }

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package com.example.myapplication; import android.media.MediaPlayer; import android.os.Bundle; import com.google.android.material.floatingactionbutton.FloatingActionButton; import com.google.android.material.snackbar.Snackbar; import androidx.appcompat.app.AppCompatActivity; import androidx.appcompat.widget.Toolbar; import android.os.Environment; import android.view.View; import android.view.Menu; import android.view.MenuItem; import android.widget.MediaController; import android.widget.Toast; import android.widget.VideoView; import java.io.File; public class MainActivity extends AppCompatActivity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); VideoView videoView = findViewById(R.id.video); File file = new File(Environment.getExternalStorageDirectory()+"/video.mp4"); if(file.exists()){ videoView.setVideoPath(file.getAbsolutePath()); }else{ return ; } // 控制视频播放 MediaController mc = new MediaController(MainActivity.this); videoView.setMediaController(mc); // videoiew 获取焦点 videoView.requestFocus(); videoView.start(); // 完成监听器 videoView.setOnCompletionListener(new MediaPlayer.OnCompletionListener() { @Override public void onCompletion(MediaPlayer mediaPlayer) { Toast.makeText(MainActivity.this,"视频播放完成",Toast.LENGTH_SHORT).show(); } }); } }

package com.example.myapplication; import android.content.Intent; import android.graphics.Bitmap; import android.graphics.BitmapFactory; import android.graphics.PixelFormat; import android.hardware.Camera; import android.net.Uri; import android.os.Bundle; import android.os.Environment; import android.provider.MediaStore; import android.view.SurfaceHolder; import android.view.SurfaceView; import android.view.View; import android.view.WindowManager; import android.widget.ImageButton; import android.widget.Toast; import androidx.appcompat.app.AppCompatActivity; import java.io.File; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.IOException; public class MainActivity extends AppCompatActivity { private Camera camera; private boolean isPreview = false; // 设置是否是预览状态 @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); //设置全屏显示 getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN); if (!android.os.Environment.getExternalStorageState().equals(  //判断手机是否安装SD卡 android.os.Environment.MEDIA_MOUNTED)) { Toast.makeText(this, "请安装SD卡！", Toast.LENGTH_SHORT).show(); // 提示安装SD卡 } // 设置预览 final SurfaceView surfaceView = findViewById(R.id.surfaceView); final SurfaceHolder surfaceHolder = surfaceView.getHolder(); // 设置自己维护缓存 surfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS); ImageButton preview = (ImageButton) findViewById(R.id.preview);        //获取“预览”按钮 ImageButton takePicture = (ImageButton) findViewById(R.id.takephoto);  //获取“拍照”按钮 preview.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { if (!isPreview) { camera = Camera.open(); isPreview = true; } try { camera.setPreviewDisplay(surfaceHolder);                   // 设置用于显示预览的SurfaceView Camera.Parameters parameters = camera.getParameters();    //获取相机参数 parameters.setPictureFormat(PixelFormat.JPEG);    //指定图片为JPEG图片 parameters.set("jpeg-quality", 80);            //设置图片的质量 camera.setParameters(parameters);                //重新设置相机参数 camera.startPreview();                            //开始预览 camera.autoFocus(null);                        //设置自动对焦 } catch (IOException e) {                           //输出异常信息 e.printStackTrace(); } } }); // 保存拍照 //实现相机拍照功能 takePicture.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { if (camera != null) {                                     //相机不为空 camera.takePicture(null, null, jpeg);                //进行拍照 } } }); } final   Camera.PictureCallback jpeg = new Camera.PictureCallback() { @Override public void onPictureTaken(byte[] data, Camera camera) { // 根据拍照所得的数据创建位图 final Bitmap bm = BitmapFactory.decodeByteArray(data, 0, data.length); camera.stopPreview();        //停止预览 isPreview = false;         //设置为非预览状态 //获取sd卡根目录 File appDir = new File(Environment.getExternalStorageDirectory(), "/DCIM/Camera/"); if (!appDir.exists()) {      //如果该目录不存在 appDir.mkdir();          //就创建该目录 } String fileName = System.currentTimeMillis() + ".jpg-600"; //将获取当前系统时间设置为照片名称 File file = new File(appDir, fileName);  //创建文件对象 try {  //保存拍到的图片 FileOutputStream fos = new FileOutputStream(file);  //创建一个文件输出流对象 bm.compress(Bitmap.CompressFormat.JPEG, 100, fos);  //将图片内容压缩为JPEG格式输出到输出流对象中 fos.flush();                                        //将缓冲区中的数据全部写出到输出流中 fos.close();                                        //关闭文件输出流对象 } catch (FileNotFoundException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } // 将照片插入到图库当中 try { MediaStore.Images.Media.insertImage(MainActivity.this.getContentResolver(), file.getAbsolutePath(),fileName,null); } catch (FileNotFoundException e) { e.printStackTrace(); } // 更新通知图库 MainActivity.this.sendBroadcast(new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE, Uri.parse("file://" + ""))); restCamera(); } }; private void restCamera(){ if(!isPreview){ camera.startPreview(); isPreview = true; } } @Override protected void onPause() {  //当暂停Activity时，停止预览并释放资源 if (camera != null) {        //如果相机不为空 camera.stopPreview();    //停止预览 camera.release();        //释放资源 } super.onPause(); } }