A library to eliminate boilerplate when querying ContentResolver and SQLiteDatabase.
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dependencies {
compile 'com.evernote:android-fetch:1.0.0'
}In its simplest form, the library enables this:
Cursor cursor;
List<String> result = new ArrayList<>();
try {
cursor = contentResolver.query(sourceUri, null, null, null, null);
while (cursor != null && cursor.moveToNext()) {
result.add(cursor.getString(0));
}
} finally {
if (cursor != null) {
cursor.close();
}
}
To become this:
List<String> result = QueryBuilder.cr(sourceUri).fetch(contentResolver).toList(Converter.STRING);Every parameter of query can be specified by calling additional optional
methods, and you can use a custom Converter to build your own objects:
List<Thing> things = QueryBuilder.db("my_table")
.projection("id", "name", "description")
.selection("size = ?")
.selectionArgs("42")
.sortOrder("name")
.fetch(database)
.toList(new Converter<Thing>() {
@Override
public Thing convert(Cursor c) {
int id = c.getInt(0);
String name = c.getString(1);
String description = c.getString(2);
return new Thing(id, name, description);
}
});There are also convenience methods for filters on list of values:
QueryBuilder.cr(sourceUri).select("name", nameList);Is equivalent to:
contentResolver.query(sourceUri, null, "name in (?,?,?)", nameList.toArray(new String[nameList.size()]), null);You can also use the RxJava binding to create an Observable from your query.
QueryBuilder.cr(MediaStore.Images.Media.EXTERNAL_CONTENT_URI)
.projection(MediaStore.Images.Media.DATA)
.selection(selection)
.fetchStream(mContext, Converter.STRING)
.map(...)
.filter(...)
.observeOn(...);Copyright 2008-2016 Evernote Corporation. All rights reserved.
Use of the source code and binary libraries included in this package
is permitted under the following terms:
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
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