mt6735 音乐播放器中显示歌曲的信息

[DESCRIPTION]
音乐播放器中显示歌曲的信息

[SOLUTION]
首先，从 database 中获取歌曲的信息 .
然后，应用 SIMpleAdapter 在 ListActivity 中显示这些信息。
在 TrackBrowserActivity 中长按一首歌曲，从 ContextMenu 中选择 METADATA_INFO ，就会启动MusicMetadataActivity ，该 Activity 会显示歌曲的信息。

具体步骤如下 :
1, 在 packages\apps\Music\androidManifest.xml 中添加 MusicMetadataActivity:
<activity android:name="com.android.music.MusicMetadataActivity"
android:exported="false"
android:theme="@android:style/Theme.Holo"
android:configChanges="orientation|screenSize" />

2, 在 packages\apps\Music\res\Layout\ 中新建布局文件 music_metadata.xml :
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
androidrientation="vertical" >
<ListView
android:id="@android:id/list"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:drawSelectorOnTop="false"
android:fastScrollEnabled="true"
android:scrollbars="none"/>
<TextView android:id="@+id/metadata_name"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="22dip"
android:textStyle="bold"
android:paddingLeft="6dip"
android:paddingTop="3dip"
android:paddingBottom="1dip"
android:gravity="center_vertical"/>
<TextView android:id="@+id/metadata_content"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="18dip"
android:textColor="@color/metadata_content"
android:paddingLeft="6dip"
android:paddingTop="1dip"
android:paddingBottom="1dip"
android:gravity="bottom"/>
</LinearLayout>

3, 在 packages\apps\Music\res\values\colors.xml 中添加颜色信息 :
<color name="metadata_content">#FF808080</color>

4, 在 packages\apps\Music\res\values\mtk_strings.xml 添加字串，并在各语言中添加对应的字串 :
<string name="music_metadata_info">Music Info</string>
<string name="music_metadata_artist">Artist</string>
<string name="music_metadata_tile">Title</string>
<string name="music_metadata_album">Album</string>
<string name="music_metadata_duration">Duration</string>
<string name="music_metadata_genre">Genre</string>
<string name="music_metadata_recording_date">Recording Date</string>
<string name="music_metadata_number">Number</string>
<string name="music_metadata_format">Format</string>
<string name="music_metadata_size">Size</string>
<string name="music_metadata_emplacement">Emplacement</string>
<string name="music_metadata_info_unknown">Unknown</string>

5, 在 packages\apps\Music\src\com\android\music\ 中创建
MusicMetadataActivity.java:
package com.android.music;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import android.app.ActionBar;
import android.app.ListActivity;
import android.content.ContentUris;
import android.content.Intent;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.provider.MediaStore;
import android.view.MenuItem;
import android.widget.SimpleAdapter;
public class MusicMetadataActivity extends ListActivity{
private static final String TAG = "MusicMetadata";
private static final String METADATA_NAME = "metadataName";
private static final String METADATA_CONTENT = "metadataContent";
private List<Map<String, String>> mListItEMS = new ArrayList<Map<String,
String>>();
private String mSelectedId;
private Cursor mCursor;
//Column Index
private int mTitleIdx;
private int mArtistIdx;
private int mAlbumIdx;
private int mDurationIdx;
private int mGenreIdx;
private int mYearIdx;
private int mTrackNoIdx;
private int MMImeTypeIdx;
private int mSizeIdx;
private int mEmplacementIdx;
//meta data
private String mTitle;
private String mArtist;
private String mAlbum;
private String mDuration;
private String mGenre;
private String mYear;
private String mTrackNo;
private String mMimeType;
private String mSize;
private String mEmplacement;
public MusicMetadataActivity()
{
}
@Override
public void onCreate(Bundle icicle) {
MusicLogUtils.d(TAG, "onCreate");
super.onCreate(icicle);
Intent intent = getIntent();
if (intent ！= null) {
mSelectedId = intent.getStringExtra("selected_id");
}
MusicLogUtils.d(TAG, "onCreate: selectedId = " + mSelectedId);
ActionBar actionBar = getActionBar();
actionBar.setDisplayHomeAsUpEnabled(true);
actionBar.setHomeButtonEnabled(true);
setContentView(R.layout.music_metadata);
//cursor column
String[] cursorCols = new String[] {
MediaStore.Audio.Media._ID,
MediaStore.Audio.Media.TITLE,
MediaStore.Audio.Media.ARTIST,
MediaStore.Audio.Media.ALBUM,
MediaStore.Audio.Media.DURATION,
MediaStore.Audio.Media.YEAR,
MediaStore.Audio.Media.TRACK,
MediaStore.Audio.Media.MIME_TYPE,
MediaStore.Audio.Media.SIZE,
MediaStore.Audio.Media.DATA
};
Uri uri =
ContentUris.withAppendedId(MediaStore.Audio.Media.EXTERNAL_CONTENT_URI,
Long.valueOf(mSelectedId));
Cursor mCursor = MusicUtils.query(this, uri, cursorCols, null, null,
null);
getColumnIndicesFROMDB(mCursor);
getMetadataFromDB(mCursor);
getGenre();
getAdapterData();
setTitle(mTitle);
initAdapter();
}
@Override
public void onDestroy() {
MusicLogUtils.d(TAG, "onDestroy");
if(mCursor ！= null){
mCursor.close();
mCursor = null;
}
super.onDestroy();
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
/// M: Navigation button press back
MusicLogUtils.d(TAG, "onOptionsItemSelected: Navigation button press
back");
finish();
return true;
default:
break;
}
return super.onOptionsItemSelected(item);
}
private void getColumnIndicesFromDB(Cursor cursor) {
MusicLogUtils.d(TAG, "getColumnIndices: cursor = " + cursor);
if(cursor ！= null){
if(cursor.moveToFirst() && cursor.getCount() > 0){
mTitleIdx = cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.TITLE);
MusicLogUtils.d(TAG, "getColumnIndices: mTitleIdx = " + mTitleIdx);
mArtistIdx = cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.ARTIST);
MusicLogUtils.d(TAG, "getColumnIndices: mArtistIdx = " + mArtistIdx);
mAlbumIdx = cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.ALBUM);
MusicLogUtils.d(TAG, "getColumnIndices: mAlbumIdx = " + mAlbumIdx);
mDurationIdx =
cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DURATION);
MusicLogUtils.d(TAG, "getColumnIndices: mDurationIdx = " + mDurationIdx);
mYearIdx = cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.YEAR);
MusicLogUtils.d(TAG, "getColumnIndices: mYearIdx = " + mYearIdx);
mTrackNoIdx = cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.TRACK);
MusicLogUtils.d(TAG, "getColumnIndices: mTrackNoIdx = " + mTrackNoIdx);
mMimeTypeIdx =
cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.MIME_TYPE);
MusicLogUtils.d(TAG, "getColumnIndices: mMimeTypeIdx = " + mMimeTypeIdx);
mSizeIdx = cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.SIZE);
MusicLogUtils.d(TAG, "getColumnIndices: mSizeIdx = " + mSizeIdx);
mEmplacementIdx =
cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DATA);
MusicLogUtils.d(TAG, "getColumnIndices: mEmplacementIdx = " +
mEmplacementIdx);
}
}
}
private void getMetadataFromDB(Cursor cursor) {
MusicLogUtils.d(TAG, "getMetadataFromDB: cursor = " + cursor);
if(cursor ！= null){
if(cursor.moveToFirst() && cursor.getCount() > 0){
mTitle = cursor.getString(mTitleIdx);
MusicLogUtils.d(TAG, "getColumnIndices: mTitle = " + mTitle);
String artist = cursor.getString(mArtistIdx);
MusicLogUtils.d(TAG, "getColumnIndices: artist = " + artist);
if(MediaStore.UNKNOWN_STRING.equals(artist)){
artist = getString(R.string.unknown_artist_name);
MusicLogUtils.d(TAG, "getColumnIndices: artist = " + artist);
}
mArtist = artist;
String album = cursor.getString(mAlbumIdx);
MusicLogUtils.d(TAG, "getColumnIndices: album = " + album);
if(MediaStore.UNKNOWN_STRING.equals(album)){
album = getString(R.string.unknown_album_name);
MusicLogUtils.d(TAG, "getColumnIndices: album = " + album);
}
mAlbum = album;
long duration = cursor.getLong(mDurationIdx);
final int secondToMs = 1000;
MusicLogUtils.d(TAG, "getColumnIndices: duration = " + duration);
mDuration = MusicUtils.makeTimeString(this, duration / secondToMs);
int year = cursor.getInt(mYearIdx);
MusicLogUtils.d(TAG, "getColumnIndices: year = " + year);
if(year == 0){
mYear = getString(R.string.music_metadata_info_unknown);
}else{
mYear = String.valueOf(year);
}
MusicLogUtils.d(TAG, "getColumnIndices: mYear = " + mYear);
int trackNo = cursor.getInt(mTrackNoIdx);
MusicLogUtils.d(TAG, "getColumnIndices: trackNo = " + trackNo);
mTrackNo = String.valueOf(trackNo);
mMimeType = cursor.getString(mMimeTypeIdx);
MusicLogUtils.d(TAG, "getColumnIndices: mMimeType = " + mMimeType);
long size = cursor.getLong(mSizeIdx);
MusicLogUtils.d(TAG, "getColumnIndices: size = " + size);
mSize = MusicUtils.makeSizeString(size);
MusicLogUtils.d(TAG, "getColumnIndices: mSize = " + mSize);
mEmplacement = cursor.getString(mEmplacementIdx);
MusicLogUtils.d(TAG, "getColumnIndices: mEmplacement = " + mEmplacement);
}
}
}
private void getGenre(){
MusicLogUtils.d(TAG, "getGenre");
String[] cursorGenreCols = new String[]{
MediaStore.Audio.Genres._ID,
MediaStore.Audio.Genres.NAME
};
Uri uri = MediaStore.Audio.Genres.getContentUriForAudioId("external",
Integer.valueOf(mSelectedId));
MusicLogUtils.d(TAG, "getGenre: uri = " + uri);
String genre = null;
Cursor genreCursor = MusicUtils.query(this, uri, cursorGenreCols, null,
null, null);
MusicLogUtils.d(TAG, "getGenre: genreCursor = " + genreCursor);
if(genreCursor ！= null){
if(genreCursor.moveToFirst() && genreCursor.getCount() > 0){
int genreIdx =
genreCursor.getColumnIndexOrThrow(MediaStore.Audio.Genres.NAME);
MusicLogUtils.d(TAG, "getGenre: nameIdx = " + genreIdx);
genre = genreCursor.getString(genreIdx);
MusicLogUtils.d(TAG, "getGenre: genre = " + genre);
}
genreCursor.close();
genreCursor = null;
}
MusicLogUtils.d(TAG, "getGenre: genreCursor");
if(genre == null){
mGenre = getString(R.string.music_metadata_info_unknown);
}else{
mGenre = genre;
}
MusicLogUtils.d(TAG, "getGenre: mGenre = " + mGenre);
}
private void getAdapterData(){
MusicLogUtils.d(TAG, "getAdapterData");
//metadata name string id
int[] metadataName = new int[]{
R.string.music_metadata_tile,
R.string.music_metadata_artist,
R.string.music_metadata_album,
R.string.music_metadata_duration,
R.string.music_metadata_genre,
R.string.music_metadata_recording_date,
R.string.music_metadata_number,
R.string.music_metadata_format,
R.string.music_metadata_size,
R.string.music_metadata_emplacement
};
//metadata content string
String[] metadataContent = new String[]{
mTitle,
mArtist,
mAlbum,
mDuration,
mGenre,
mYear,
mTrackNo,
mMimeType,
mSize,
mEmplacement
};
for(int i = 0; i < metadataName.length; i++){
Map<String, String> listItem = new HashMap<String, String>();
listItem.put(METADATA_NAME, getString(metadataName));
listItem.put(METADATA_CONTENT, metadataContent);
mListItems.add(listItem);
}
}
private void initAdapter(){
MusicLogUtils.d(TAG, "initAdapter");
String[] from = new String[]{METADATA_NAME, METADATA_CONTENT};
int[] to = new int[]{R.id.metadata_name, R.id.metadata_content};
SimpleAdapter simpleAdapter = new SimpleAdapter(this, mListItems,
R.layout.music_metadata, from, to);
setListAdapter(simpleAdapter);
}
}

6, 在 packages\apps\Music\src\com\android\music\ MusicUtils.Java 中添加转换时间格式的方法 :
public static final String UNIT_B = "B";
public static final String UNIT_KB = "KB";
public static final String UNIT_MB = "MB";
public static final String UNIT_GB = "GB";
public static final String UNIT_TB = "TB";
private static final int UNIT_INTERVAL = 1024;
private static final double ROUNDING_OFF = 0.005;
private static final int DECIMAL_NUMBER = 100;
/**
* This method converts a size to a string
*
* @param size the size of a file
* @return the string represents the size
*/
public static String makeSizeString(long size) {
String unit = UNIT_B;
if (size < DECIMAL_NUMBER) {
MusicLogUtils.d(TAG, "makeSizeString(),size = " + size);
return Long.toString(size) + " " + unit;
}
unit = UNIT_KB;
double sizeDouble = (double) size / (double) UNIT_INTERVAL;
if (sizeDouble > UNIT_INTERVAL) {
sizeDouble = (double) sizeDouble / (double) UNIT_INTERVAL;
unit = UNIT_MB;
}
if (sizeDouble > UNIT_INTERVAL) {
sizeDouble = (double) sizeDouble / (double) UNIT_INTERVAL;
unit = UNIT_GB;
}
if (sizeDouble > UNIT_INTERVAL) {
sizeDouble = (double) sizeDouble / (double) UNIT_INTERVAL;
unit = UNIT_TB;
}
// Add 0.005 for rounding-off.
long sizeInt = (long) ((sizeDouble + ROUNDING_OFF) * DECIMAL_NUMBER); //
strict to two
// decimal places
double formatedSize = ((double) sizeInt) / DECIMAL_NUMBER;
MusicLogUtils.d(TAG, "makeSizeString(): " + formatedSize + unit);
if (formatedSize == 0) {
return "0" + " " + unit;
} else {
return Double.toString(formatedSize) + " " + unit;
}
}

7, 在 packages\apps\Music\src\com\android\music\ TrackBrowserActivity.java 中添加启动 MusicMetadataActivity 的入口 :
a, 定义启动 MusicMetadataActivity 的 menu item:
private static final int METADATA_INFO = CHILD_MENU_BASE + 10;
b, 在 onCreateContextMenu() 中添加该 menu item:
menu.add(0, METADATA_INFO, 0, R.string.music_metadata_info);
c, 在 onContextItemSelected() 执行启动 MusicMetadataActivity 的操作 :
case METADATA_INFO:
Intent intent = new Intent();
intent.setClass(this, MusicMetadataActivity.class);
intent.putExtra("selected_id", String.valueOf(mSelectedId));
MusicLogUtils.d(TAG, "METADATA_INFO: mSelectedPosition = " +
mSelectedPosition);
MusicLogUtils.d(TAG, "METADATA_INFO: mSelectedId = " + mSelectedId);
startActivityForResult(intent, -1);
return true;