下面插入铃声的代码，在调用下面代码的时候会出现返回null。而且没有任何报错信息。查了很久都无法找到原因。
final Uri newUri = getContentResolver().insert(uri, values);
然后改用update尝试，出现错误信息，错误提示是 "_data is not unique".
getContentResolver().update(uri, values, null, null);
分析原因可能是以前有这个column 记录不唯一。
所以在
final Uri newUri = getContentResolver().insert(uri, values);
前加上删除记录，问题解决。
getContentResolver().delete(uri, null, null);
调用方法：
setUserCustomVoice(outPathRingFile,RingtoneManager.TYPE_ALARM);
private void setUserCustomVoice (String path, int type)
{
/*Sometimes, this function will be failed because of the wrong path.
* Only the path "/sdcard/media/audio/ringtones/" is available to set ring.
* For example:
* setUserCustomVoice("/sdcard/media/audio/ringtones/wang.mp3",RingtoneManager.TYPE_ALARM);
*/
File sdfile = new File(path);
String mimeType = "audio/*";
ContentValues values = new ContentValues();
values.put(MediaStore.MediaColumns.DATA, sdfile.getAbsolutePath());
values.put(MediaStore.MediaColumns.TITLE, sdfile.getName());
values.put(MediaStore.MediaColumns.MIME_TYPE, mimeType);
values.put(MediaStore.MediaColumns.SIZE, sdfile.length());
values.put(MediaStore.Audio.Media.IS_RINGTONE, false);
values.put(MediaStore.Audio.Media.IS_NOTIFICATION, false);
values.put(MediaStore.Audio.Media.IS_ALARM, false);
values.put(MediaStore.Audio.Media.IS_MUSIC, false);
switch (type)
{
case RingtoneManager.TYPE_NOTIFICATION:
values.put(MediaStore.Audio.Media.IS_NOTIFICATION, true);
break;
case RingtoneManager.TYPE_ALARM:
values.put(MediaStore.Audio.Media.IS_ALARM, true);
break;
case RingtoneManager.TYPE_RINGTONE:
values.put(MediaStore.Audio.Media.IS_RINGTONE, true);
break;
default:
type = RingtoneManager.TYPE_ALL;
values.put(MediaStore.Audio.Media.IS_MUSIC, true);
break;
}
System.out.println("values: " + values);
System.out.println("Ring absPath: " + sdfile.getAbsolutePath());
System.out.println("RingPath: " + path);
Uri uri = MediaStore.Audio.Media.getContentUriForPath(sdfile.getAbsolutePath());
System.out.println("uri: " + uri);
getContentResolver().delete(uri, null, null);
/*The following code always returns null, Why Why */
final Uri newUri = getContentResolver().insert(uri, values);
//getContentResolver().update(uri, values, null, null);
System.out.println("newUri: "+newUri);
RingtoneManager.setActualDefaultRingtoneUri(RingToneTailor.this, type, newUri);
}
final Uri newUri = getContentResolver().insert(uri, values);