如何根据时间来排序光标 [英] How to sort a cursor based on a time string

问题描述

我的问题，如果很简单，我有code的这一部分。

My question if fairly simple, I have this segment of code

Cursor mCursor = this.getContentResolver().query(
            PlayerContentProviderDB.CONTENT_URI, fulldataColumns, null, null,
            Players.SCORE +" ASC");

这code，从一切我所看到的，应以升序排列光标基于Players.SCORE，但事实并非如此。

This code, from everything I've seen, should be sorting the cursor in ascending order based on Players.SCORE but it is not.

有关参考Players.SCORE总是会在格式结果字符串
MM：SS：msmsms（读分钟：秒：毫秒​​）。

For reference Players.SCORE will always be a string in the format
mm:ss:msmsms ( read minute:second:millisecond).

另外这里是code在我的ContentProvider查询方法

Also here is the code for the query method in my ContentProvider

public Cursor query(Uri uri, String[] projection, String selection,
        String[] selectionArgs, String sortOrder) {
    SQLiteQueryBuilder queryBuilder = new SQLiteQueryBuilder();
    checkColumns(projection);
    queryBuilder.setTables(PlayerContract.Players.PLAYERS_TABLE_NAME);
    int uriType = sURIMatcher.match(uri);
    switch (uriType) {
    case ALL_SCORES:
    break;
    case SCORE_ID:
    queryBuilder.appendWhere(PlayerContract.Players.ID + "="
    + uri.getLastPathSegment());
    break;
    default:
    throw new IllegalArgumentException("Unknown URI: " + uri);
    }
    SQLiteDatabase db = this.dbHelper.getReadableDatabase(); 
    Cursor cursor = queryBuilder.query(db, projection, selection,
    selectionArgs, null, null, sortOrder);
    // Notify potential listeners
    cursor.setNotificationUri(getContext().getContentResolver(), uri);
    return cursor;

我的问题是，为什么这剂code没有工作，我该如何解决？

My question is why dose this code not work and how can I fix it?

（这个code另一个有趣的现象是，我也试图限制语句添加到排序，我已经读了作品的结尾，但是我的是不是）

(Another interesting note about this code is that I am also trying to add a limit statement to the end of the sort, which I have read works, however mine is not)

推荐答案

我终于找到了这个问题的答案。事实证明我的code是正确的，但出于某种原因，我仍然对我的工作ContentProvider.query（）被调用两次。一旦与正确的参数并再次用不正确的参数。（即：中将sortOrder == NULL）

I finally found the answer to this question. As it turns out my code was correct, however for some reason that I am still working on my ContentProvider.query() was being called twice. Once with the correct parameters and again with incorrect parameters.(i.e: sortOrder == null).

另外请注意，您可以按数字顺序为SQL不同排序整数和字符串不排序的一串数字

Also note that you can not sort a string of numbers in numerical order as sql sorts ints and strings differently

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