我正在尝试使用带有托管查询的光标来过滤设备上的媒体内容
String[] dirs = new String[] {"%"+ dir + "%"};
String[] musicdata = { BaseColumns._ID,
MediaColumns.DATA,
MediaColumns.DISPLAY_NAME,
MediaColumns.SIZE };
musiccursor = getActivity().getContentResolver().query(
MediaStore.Audio.Media.EXTERNAL_CONTENT_URI,
musicdata,
MediaColumns.DATA + " like ? ",
dirs,
MediaColumns.DATA + " asc");
查询的where子句使用传递给它的目录,以便过滤该文件夹和子文件夹中的音乐。
我想要做的是在同一个查询中包含“不喜欢”。
这样做的原因是用户能够从列表视图中排除文件夹,并将其存储在数组中并写入文件以保留选择。我希望光标查询将这些排除项考虑在内,同时仍然链接到它们传递给它的文件夹。
提前致谢!
答案 0 :(得分:1)
在回答我自己的查询时,这里是代码:
//Build the where clause
StringBuilder where = new StringBuilder();
//first add in all values from the exclusion array
for (int i = 0; i < excludedFolders.size(); i++) {
where.append(MediaColumns.DATA + " not like ? ");
where.append(" AND ");
}
//then add in the final like clause, e.g. the folder the user selected
where.append(MediaColumns.DATA + " like ? ");
//convert it to a string
String selection = where.toString();
System.out.println(selection);
////////////////////////////////////////////////////////////////////////////////////////////
//Build the arguments. the array is set to the size of the exlcusion list, plus 1 for the fodler selected
String[] dirs = new String[excludedFolders.size()+1];
System.out.println(excludedFolders.size()+1);
//first add in a value for each excluded folder
for (int i = 0; i < excludedFolders.size(); i++) {
dirs[i] = "%" + excludedFolders.get(i) + "%";
System.out.println(i + " " + dirs[i]);
}
//add the argument value for the like element of the query
dirs[excludedFolders.size()]="%"+ dir + "%";
System.out.println("excludedFolders.size() " + dirs[excludedFolders.size()]);
//start building the cursor
String[] musicdata = { BaseColumns._ID,
MediaColumns.DATA,
MediaColumns.DISPLAY_NAME,
MediaColumns.SIZE };
//run the query
musiccursor = getActivity().getContentResolver().query(
MediaStore.Audio.Media.EXTERNAL_CONTENT_URI,
musicdata,
selection,
dirs,
MediaColumns.DATA+ " asc");
//done