我正在实现一个AutoCompleteTextView,我需要所有联系人的姓名和电子邮件.
我发现这个代码段我异步运行,但是速度非常慢.
我发现这个代码段我异步运行,但是速度非常慢.
ContentResolver cr = getContentResolver();
Cursor cur = cr.query(ContactsContract.Contacts.CONTENT_URI,null,null);
if (cur.getCount() > 0) {
while (cur.moveToNext()) {
String id = cur.getString(cur.getColumnIndex(ContactsContract.Contacts._ID));
String name = cur.getString(cur.getColumnIndex(ContactsContract.Contacts.DISPLAY_NAME));
Cursor emailCur = cr.query(ContactsContract.CommonDataKinds.Email.CONTENT_URI,ContactsContract.CommonDataKinds.Email.CONTACT_ID + " = ?",new String[]{id},null);
while (emailCur.moveToNext()) {
String email = emailCur.getString(emailCur.getColumnIndex(ContactsContract.CommonDataKinds.Email.DATA));
autoCompleteAdapter.add(name + " - " + email);
}
emailCur.close();
}
}
}
我正在执行一种内部查询,我认为这是问题.有没有办法调整它,使它更快？
解决方法
private static final String[] PROJECTION = new String[] {
ContactsContract.CommonDataKinds.Email.CONTACT_ID,ContactsContract.Contacts.DISPLAY_NAME,ContactsContract.CommonDataKinds.Email.DATA
};
...
ContentResolver cr = getContentResolver();
Cursor cursor = cr.query(ContactsContract.CommonDataKinds.Email.CONTENT_URI,PROJECTION,null);
if (cursor != null) {
try {
final int contactIdIndex = cursor.getColumnIndex(ContactsContract.CommonDataKinds.Email.CONTACT_ID);
final int displayNameIndex = cursor.getColumnIndex(ContactsContract.Contacts.DISPLAY_NAME);
final int emailIndex = cursor.getColumnIndex(ContactsContract.CommonDataKinds.Email.DATA);
long contactId;
String displayName,address;
while (cursor.moveToNext()) {
contactId = cursor.getLong(contactIdIndex);
displayName = cursor.getString(displayNameIndex);
address = cursor.getString(emailIndex);
...
}
} finally {
cursor.close();
}
}
少数笔记：
>仅使用ContactsContract.CommonDataKinds.Email.CONTENT_URI获取所需的信息,请参阅ContactsContract.CommonDataKinds.Email了解可以查询哪些列>使用投影只能获得真正需要的列,节省一些内存并增加查询性能>仅在while循环之前获取列索引一次
