Question

我是Android开发的新手。在我的音乐播放器应用程序中，每当我点击播放/暂停按钮暂停歌曲时，都没有任何反应。看起来图像按钮不可点击，因为触摸它时没有任何反应。我无法暂停播放这首歌。我已经尝试了堆栈溢出时提到的所有可能的解决方案仍然无法正常工作。任何人都可以告诉我我做错了什么？

XML文件：

  <LinearLayout
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:gravity="center_vertical"
            android:orientation="horizontal"
            android:paddingLeft="10dp"
            android:paddingRight="10dp"
            android:weightSum="1">

            <RelativeLayout
                android:layout_width="300dp"
                android:layout_height="match_parent"
                android:background="@android:color/holo_blue_bright">


                <ImageButton
                    android:id="@+id/btnPrevious"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_alignParentLeft="true"
                    android:layout_weight="2.40"
                    android:background="@null"
                    android:paddingLeft="10dp"
                    android:src="@drawable/btn_previous" />

                <ImageButton
                    android:id="@+id/btnPlay1"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_centerInParent="true"
                    android:clickable="true"
                    android:background="@drawable/btn_play" />


                <ImageButton
                    android:id="@+id/btnNext"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:background="@null"
                    android:paddingLeft="230dp"
                    android:src="@drawable/btn_next" />
            </RelativeLayout>
        </LinearLayout>

btn_play.xml：

<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:drawable="@drawable/download4"
        android:state_enabled="false" />
    <item android:drawable="@drawable/az"
        android:state_enabled="true" />
</selector>

PlayListActivity.java：

 @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_play_list);

        mMediaPlayer = new MediaPlayer();
        ListView mListView = (ListView) findViewById(R.id.list);

        mMusicList = getAudioList();

   ArrayAdapter<String> mAdapter = new ArrayAdapter<>(this,
                android.R.layout.simple_list_item_1, mMusicList);
        mListView.setAdapter(mAdapter);

        mListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {

            @Override
            public void onItemClick(AdapterView<?> arg0, View view, int arg2,
                                    long arg3) {

                try {
                    playSong(mAudioPath[arg2]);
                } catch (IllegalArgumentException e) {
                    e.printStackTrace();
                } catch (IllegalStateException e) {
                    e.printStackTrace();
                } catch (IOException e) {
                    e.printStackTrace();
                }

            }
        });
    }

    private String[] getAudioList() {
        final Cursor mCursor = getContentResolver().query(
                MediaStore.Audio.Media.EXTERNAL_CONTENT_URI,
                new String[]{MediaStore.Audio.Media.DISPLAY_NAME, MediaStore.Audio.Media.DATA}, null, null,
                "LOWER(" + MediaStore.Audio.Media.TITLE + ") ASC");

        int count = mCursor.getCount();

        String[] songs = new String[count];
        mAudioPath = new String[count];
        int i = 0;
        if (mCursor.moveToFirst()) {
            do {
                songs[i] = mCursor.getString(mCursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DISPLAY_NAME));
                mAudioPath[i] = mCursor.getString(mCursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DATA));
                i++;
            } while (mCursor.moveToNext());
        }

        mCursor.close();

        return songs;
    }


    private void playSong(String path) throws IllegalArgumentException,
            IllegalStateException, IOException {

        setContentView(R.layout.activity_android_building_music_player);
        Log.d("ringtone", "playSong :: " + path);

        mMediaPlayer.reset();
        mMediaPlayer.setDataSource(path);
//mMediaPlayer.setLooping(true);
        mMediaPlayer.prepare();
        mMediaPlayer.start();
        acv(path);
        abc();
    }

    public void acv(String path) {
        getInit();

        metaRetriver = new MediaMetadataRetriever();
        metaRetriver.setDataSource(path);
        try {
            art = metaRetriver.getEmbeddedPicture();
            Bitmap songImage = BitmapFactory.decodeByteArray(art, 0, art.length);
            album_art.setImageBitmap(songImage);
            album.setText(metaRetriver
                    .extractMetadata(MediaMetadataRetriever.METADATA_KEY_ALBUM));
            artist.setText(metaRetriver
                    .extractMetadata(MediaMetadataRetriever.METADATA_KEY_ARTIST));
        } catch (Exception e) {
            album_art.setBackgroundColor(Color.GRAY);
            album.setText("Unknown Album");
            artist.setText("Unknown Artist");
        }

    }

    public void getInit() {
        album_art = (ImageView) findViewById(R.id.coverart1);
        album = (TextView) findViewById(R.id.Album);
        artist = (TextView) findViewById(R.id.artist_name);
    }


    public  void abc(){
        ImageButton btnPlay1 = (ImageButton) findViewById(R.id.btnPlay1);
        btnPlay1.setOnClickListener(
                new ImageButton.OnClickListener(){
                    public void onClick(View v){
                        if (mMediaPlayer.isPlaying()) {
                            mMediaPlayer.pause();
                        } else {
                            mMediaPlayer.start();
                        }

                    }
                });
    }

Answer 1

你的适配器看起来不在同一个LayoutXML中，也许你的findViewById（R.id.btnPlay1）返回null。

Answer 2

您的听众将其更改为：

btnPlay1.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        Toast.makeText(Act.this, "test click", Toast.LENGTH_SHORT).show();
    }
});

暂停按钮在音乐播放器

2 个答案: