『牛角书』基于鸿蒙开发小小音乐播放器

标签：播放器牛角鸿蒙 list resultSet musicBean private ohos new

鸿蒙开发小应用-音乐播放器

话不多说，展示。

第一次进去会申请访问权限，点击“始终允许”

『牛角书』基于鸿蒙开发小小音乐播放器_Text

点击“始终允许”后退出一下，再次点击进入该应用会看到一首音乐Dream it Possible，因为模拟器上只有这一首主题曲，可以点击播放。

『牛角书』基于鸿蒙开发小小音乐播放器_Text_02

播放器内容包括：播放器名称，音乐名，音乐作曲家，背景图，三个控制播放/暂停，上一曲/下一曲的按钮。

开发导图

一：资源获取

权限申请

@Override
    public void onStart(Intent intent) {
        super.onStart(intent);
        super.setMainRoute(MainAbilitySlice.class.getName());

        if (verifySelfPermission("ohos.permission.READ_MEDIA") != IBundleManager.PERMISSION_GRANTED) {
            if (canRequestPermission("ohos.permission.READ_MEDIA")) {
                // 是否可以申请弹框授权(首次申请或者用户未选择禁止且不再提示)
                requestPermissionsFromUser(
                        new String[]{"ohos.permission.READ_MEDIA"}, MY_PERMISSIONS_REQUEST_RW);
            } else {
                new ToastDialog(this).setText("需要授予应用读取存储权限").setAlignment(LayoutAlignment.CENTER).show();
            }
        }
    }

当权限可以申请时需要重写下面的方法，获取权限申请的结果

@Override
    public void onRequestPermissionsFromUserResult(int requestCode, String[] permissions, int[] grantResults) {
        if (requestCode == MY_PERMISSIONS_REQUEST_RW) {// 匹配requestPermissions的requestCode
            if (grantResults.length > 0
                    && grantResults[0] == IBundleManager.PERMISSION_GRANTED) {
                new ToastDialog(this).setText("所有权限已经被授予").setAlignment(LayoutAlignment.CENTER).show();
            } else {
                new ToastDialog(this).setText("所有权限已经被拒绝").setAlignment(LayoutAlignment.CENTER).show();
            }
        }
    }

数据模型

一个音乐的实体类

public class MusicBean {
    private int id;
    private String title;
    private String song;
    private String data;
    private String duration;
    private String artist;
    private String album;
    构造方法，get,set方法省略
    }

数据读取

数据读取需要做两件事1.通过访问外部存储的URL获取ResultSet

private ResultSet queryAvStore(Context context) {
        ResultSet resultSet = null;
        DataAbilityHelper helper = DataAbilityHelper.creator(context);
        try {
            resultSet = helper.query(AVStorage.Audio.Media.EXTERNAL_DATA_ABILITY_URI, null, null);
        } catch (DataAbilityRemoteException e) {
            e.printStackTrace();
        }
        return resultSet;
    }

2.通过ResultSet获取到数据

private List<MusicBean> getMusicBeanList(Context context) {
        ResultSet resultSet = queryAvStore(context);
        List<MusicBean> musicBeans = new ArrayList<>();
        while (resultSet.goToNextRow()) {
            MusicBean musicBean = new MusicBean();
            musicBean.setId(resultSet.getInt(resultSet.getColumnIndexForName(AVStorage.AVBaseColumns.ID)));
            musicBean.setData(resultSet.getString(resultSet.getColumnIndexForName(AVStorage.AVBaseColumns.DATA)));
            musicBean.setTitle(resultSet.getString(resultSet.getColumnIndexForName(AVStorage.AVBaseColumns.TITLE)));
            musicBean.setDuration(new SimpleDateFormat("mm:ss").format(new Date(resultSet.getLong(resultSet.getColumnIndexForName(AVStorage.AVBaseColumns.DURATION)))));
            musicBean.setSong(resultSet.getString(resultSet.getColumnIndexForName(AVStorage.AVBaseColumns.DISPLAY_NAME)));
            musicBean.setArtist(resultSet.getString(resultSet.getColumnIndexForName("artist")));
            musicBean.setAlbum(resultSet.getString(resultSet.getColumnIndexForName("album")));
            musicBeans.add(musicBean);
        }
        return musicBeans;
    }

二：UI界面

布局

<DirectionalLayout
    xmlns:ohos="http://schemas.huawei.com/res/ohos"
    ohos:width="match_parent"
    ohos:height="match_parent"
    ohos:orientation="vertical">
    <ListContainer
        ohos:id="$+id:music_bean_lc"
        ohos:height="0vp"
        ohos:width="match_parent"
        ohos:orientation="vertical"
        ohos:weight="1"
        ohos:background_element="$media:background"/>
    <DirectionalLayout
        ohos:height="match_content"
        ohos:width="match_parent"
        ohos:background_element="#E6000000"
        ohos:orientation="horizontal"
        ohos:padding="5vp">
        <DirectionalLayout
            ohos:height="match_content"
            ohos:width="0vp"
            ohos:weight="1"
            ohos:orientation="vertical"
            ohos:layout_alignment="vertical_center">
            <Text
                ohos:id="$+id:bottom_music_name_tv"
                ohos:height="match_content"
                ohos:width="match_content"
                ohos:text="$string:music_name"
                ohos:text_size="20fp"
                ohos:text_color="$color:color_white"/>
            <Text
                ohos:id="$+id:bottom_music_artists_tv"
                ohos:height="match_content"
                ohos:width="match_content"
                ohos:text="$string:music_artist"
                ohos:text_size="10fp"
                ohos:text_color="$color:color_white"/>
        </DirectionalLayout>
        <Button
            ohos:id="$+id:bottom_last_btn"
            ohos:height="50vp"
            ohos:width="50vp"
            ohos:margin="10vp"
            ohos:background_element="$graphic:ic_last"/>
        <Button
            ohos:id="$+id:bottom_play_btn"
            ohos:height="50vp"
            ohos:width="50vp"
            ohos:margin="10vp"
            ohos:background_element="$graphic:ic_play"/>
        <Button
            ohos:id="$+id:bottom_next_btn"
            ohos:height="50vp"
            ohos:width="50vp"
            ohos:margin="10vp"
            ohos:background_element="$graphic:ic_next"/>
    </DirectionalLayout>
</DirectionalLayout>

『牛角书』基于鸿蒙开发小小音乐播放器_Text_03

ListContainer

@Override
    public int getCount() {
        return list == null ? 0 : list.size();
    }

    @Override
    public Object getItem(int position) {
        if (list != null && position >= 0 && position < list.size()) {
            return list.get(position);
        }
        return null;
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

    @Override
    public Component getComponent(int i, Component component, ComponentContainer componentContainer) {
        final Component cpt;
        if (component == null) {
            cpt = LayoutScatter.getInstance(abilitySlice).parse(ResourceTable.Layout_item_music_bean, null, false);
        } else {
            cpt = component;
        }
        MusicBean musicBean = list.get(i);
        Text nameTv = (Text) cpt.findComponentById(ResourceTable.Id_music_name_tv);
        nameTv.setText(musicBean.getTitle());
//        Text dataTv = (Text) cpt.findComponentById(ResourceTable.Id_music_data_tv);
//        dataTv.setText(musicBean.getSong());
        Text durationTv = (Text) cpt.findComponentById(ResourceTable.Id_music_duration_tv);
        durationTv.setText(musicBean.getDuration());
        Text artistTv = (Text) cpt.findComponentById(ResourceTable.Id_music_artists_tv);
        artistTv.setText(musicBean.getArtist() + "-" + musicBean.getAlbum());
        return cpt;
    }
}

三：播放逻辑

List Item点击事件

private void initListContainer() {
        ListContainer listContainer = (ListContainer) findComponentById(ResourceTable.Id_music_bean_lc);
        list = getMusicBeanList(this);
        MusicBeanProvider musicBeanProvider = new MusicBeanProvider(list, this);
        listContainer.setItemProvider(musicBeanProvider);
        listContainer.setItemClickedListener((listContainer1, component, i, l) -> {
 
            MusicBean item = (MusicBean) listContainer1.getItemProvider().getItem(i);

            currentPlayMusicPos = i;
            musicNameTv.setText(item.getTitle());
            musicArtistTv.setText(item.getArtist()+"-"+item.getAlbum());
         
            playBtn.setBackground(new VectorElement(this,ResourceTable.Graphic_ic_pause));

            try {
                if (PlayManager.getInstance().play(new Source(DataAbilityHelper
                                        .creator(component.getContext())
                                        .openFile(Uri.appendEncodedPathToUri(AVStorage.Audio.Media.EXTERNAL_DATA_ABILITY_URI, String.valueOf(item.getId())), "r")),0)) {
                    HiLog.info(hiLogLabel, "播放成功");
                } else {
                    HiLog.info(hiLogLabel, "播放失败");
                }
            } catch (DataAbilityRemoteException | FileNotFoundException e) {
                e.printStackTrace();
                HiLog.info(hiLogLabel, "播放失败");
            }
        });
    }

更新底部播放栏的信息，依据音频播成开发指导创建播放服务管埋PlayManager方法类，并在其内部音乐播放、香停、饮复等功能，以便在
Abilityslice中的调用。

底部控制栏

private int currentPlayMusicPos = -1;

当前播放索引为-1表示没有音乐在播放

private void playMusic(Context context){
        if(currentPlayMusicPos == -1){
            new ToastDialog(context).setText("请从播放列表中选择歌曲").setAlignment(LayoutAlignment.CENTER).show();
        }else{
            if(PlayManager.getInstance().isPlaying()){
                PlayManager.getInstance().pause();
                playBtn.setBackground(new VectorElement(this,ResourceTable.Graphic_ic_play));
            }else{
                MusicBean item = list.get(currentPlayMusicPos);
                play(item,context,PlayManager.getInstance().getAudioCurrentPosition());
            }
        }
    }

    private void nextMusic(Context context){
        currentPlayMusicPos++;
        if (currentPlayMusicPos >= list.size()) {
            currentPlayMusicPos = 0;
        }
        MusicBean item = list.get(currentPlayMusicPos);
        play(item,context,0);
    }

    private void lastMusic(Context context){
        currentPlayMusicPos--;
        if (currentPlayMusicPos < 0) {
            currentPlayMusicPos = list.size() - 1;
        }
        MusicBean item = list.get(currentPlayMusicPos);
        play(item,context,0);
    }

标签：播放器,牛角,鸿蒙,list,resultSet,musicBean,private,ohos,new
From： https://blog.51cto.com/u_15244322/5950836

『牛角书』基于鸿蒙开发小小音乐播放器

鸿蒙开发小应用-音乐播放器

开发导图

一：资源获取

权限申请

数据模型

数据读取

二：UI界面

布局

ListContainer

三：播放逻辑

List Item点击事件

底部控制栏

相关文章

赞助商

阅读排行

『牛角书』基于鸿蒙开发小小音乐播放器

鸿蒙开发小应用-音乐播放器

开发导图

一：资源获取

权限申请

数据模型

数据读取

二：UI界面

布局

ListContainer

三： 播放逻辑

List Item点击事件

底部控制栏

相关文章

赞助商

阅读排行

三：播放逻辑