ListView控件，SimpleCursorAdapter，一个一个EditText过滤器 - 为什么不能做任何事情？ [英] ListView, SimpleCursorAdapter, an an EditText filter -- why won't it do anything?

问题描述

我想用一个EditText框正上方过滤SimpleCursorAdapter驱动的ListView。我有以下的code，但是当我在框中键入，没有任何反应;完整列表继续显示。我究竟做错了什么？

I'd like to filter a SimpleCursorAdapter-driven ListView with an EditText box right above it. I have the following code, but when I type in the box, nothing happens; the full list continues to display. What am I doing wrong?

    mCursor = getDirectoryList(null);

    adapter = new SimpleCursorAdapter(this,
            R.layout.directory_people_item, mCursor,
            new String[]{
                directoryPeople.LAST_NAME,
                directoryPeople.FIRST_NAME,
                directoryPeople.MIDDLE_NAME,
                directoryPeople.JOB_TITLE},
            new int[]{
                R.id.txtLastName,
                R.id.txtFirstName,
                R.id.txtMiddle,
                R.id.txtTitle} 
    ); 

    ListView av = (ListView)findViewById(R.id.listPeople);
    av.setAdapter(adapter);
    av.setFastScrollEnabled(true);
    av.setTextFilterEnabled(true);

    EditText etext=(EditText)findViewById(R.id.search_box);
    etext.addTextChangedListener(new TextWatcher() {
        public void onTextChanged(CharSequence s, int start, int before, int count) {
        }

        public void beforeTextChanged(CharSequence s, int start, int count, int after) {
        }

        public void afterTextChanged(Editable s) {
            ListView av = (ListView)findViewById(R.id.listPeople);
            SimpleCursorAdapter filterAdapter = (SimpleCursorAdapter)av.getAdapter();
            filterAdapter.getFilter().filter(s.toString());
        }
    });

    adapter.setFilterQueryProvider(new FilterQueryProvider() {
        public Cursor runQuery(CharSequence constraint) {
            return getDirectoryList(constraint);
        }
    });

而这里的 getDirectoryList（）：

public Cursor getDirectoryList (CharSequence constraint)  {
    SQLiteQueryBuilder queryBuilder = new SQLiteQueryBuilder();
    queryBuilder.setTables(
        directoryPeople.PEOPLE_TABLE
    );

    String asColumnsToReturn[] = { 
            directoryPeople.PEOPLE_TABLE + "."
            + directoryPeople.LAST_NAME + "," +
            directoryPeople.PEOPLE_TABLE + "."
            + directoryPeople.FIRST_NAME + "," +
            directoryPeople.PEOPLE_TABLE + "."
            + directoryPeople.MIDDLE_NAME + "," +
            directoryPeople.PEOPLE_TABLE + "."
            + directoryPeople.JOB_TITLE + "," +
            directoryPeople.PEOPLE_TABLE + "."
            + directoryPeople._ID
    };

    if (constraint == null  ||  constraint.length () == 0)  {
        //  Return the full list
        return queryBuilder.query(mDB, asColumnsToReturn, null, null,
                null, null, directoryPeople.DEFAULT_SORT_ORDER);
    }  else  {
        return mDB.query(directoryPeople.PEOPLE_TABLE, asColumnsToReturn, "LAST_NAME like '%'" + 
            constraint.toString() + "'%'", null, null, null,
            "CASE WHEN LAST_NAME like '" + constraint.toString() +
            "%' THEN 0 ELSE 1 END, LAST_NAME");
    }
}

我已经试过所有的例子，并回答我遇到我的搜索，但都无济于事。这是令人沮丧，你可以想像。在此先感谢的人谁可以帮助！

I've tried every example and answer I've come across in my searches, but to no avail. It's frustrating, as you can imagine. Thanks in advance for anyone who can help!

推荐答案

试试这个方法：

}  else  {
    String value = "%"+constraint.toString()+"%";

    return mDB.query(directoryPeople.PEOPLE_TABLE, asColumnsToReturn, "LAST_NAME like ? ", new String[]{value}, null, null, null);
}

我跳过最后一个参数，因为我不知道什么是真正应该做的：

I skipped the last argument because I don't know what it really should do:

"CASE WHEN LAST_NAME like '" + constraint.toString() + "%' THEN 0 ELSE 1 END, LAST_NAME"

您是否尝试过在模拟器此查询的壳呢？

Have you tried this query in shell in emulator?

这篇关于ListView控件，SimpleCursorAdapter，一个一个EditText过滤器 - 为什么不能做任何事情？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！