安卓ApiDemos学习 app/Activity/QuickContactsDemo

这是一个ContentResolver应用的例子首先构筑CursorString select = "((" + Contacts.DISPLAY_NAME + " NOTNULL) AND ("+ Contacts.HAS_PHONE_NUMBER + "=1) AND ("+ Contacts.DI

123bobo

1105人浏览 · 2011-10-25 21:43:46

123bobo · 2011-10-25 21:43:46 发布

这是一个ContentResolver应用的例子

首先构筑Cursor

        String select = "((" + Contacts.DISPLAY_NAME + " NOTNULL) AND ("
                + Contacts.HAS_PHONE_NUMBER + "=1) AND ("
                + Contacts.DISPLAY_NAME + " != '' ))";
        Cursor c =
                getContentResolver().query(Contacts.CONTENT_URI, CONTACTS_SUMMARY_PROJECTION, select,
                null, Contacts.DISPLAY_NAME + " COLLATE LOCALIZED ASC");

检索条件用的SQLite语法

query方法中，第一个参数是数据提供者的URI：Contacts.CONTENT_URI --通信录

第二个参数是需要返回的列

第三个参数是检索条件

COLLATE LOCALIZED 表示用本地语言文字排序

紧接着，调用startManagingCursor(c);

将Cursor的生命周期与Activity同步。这样就可以不用显示关闭Cursor了

本例中，主画面是一个ListActivity,所以使用如下语句绑定

        ContactListItemAdapter adapter = new ContactListItemAdapter(this, R.layout.quick_contacts, c);
        setListAdapter(adapter);

下面是核心，自定义的ResourceCursorAdapter

    private final class ContactListItemAdapter extends ResourceCursorAdapter {
        public ContactListItemAdapter(Context context, int layout, Cursor c) {
            super(context, layout, c);
        }

        @Override
        public void bindView(View view, Context context, Cursor cursor) {
            final ContactListItemCache cache = (ContactListItemCache) view.getTag();
            TextView nameView = cache.nameView;
            QuickContactBadge photoView = cache.photoView;
            // Set the name
            cursor.copyStringToBuffer(SUMMARY_NAME_COLUMN_INDEX, cache.nameBuffer);
            int size = cache.nameBuffer.sizeCopied;
            cache.nameView.setText(cache.nameBuffer.data, 0, size);
            final long contactId = cursor.getLong(SUMMARY_ID_COLUMN_INDEX);
            final String lookupKey = cursor.getString(SUMMARY_LOOKUP_KEY);
            cache.photoView.assignContactUri(Contacts.getLookupUri(contactId, lookupKey));
        }

        @Override
        public View newView(Context context, Cursor cursor, ViewGroup parent) {
            View view = super.newView(context, cursor, parent);
            ContactListItemCache cache = new ContactListItemCache();
            cache.nameView = (TextView) view.findViewById(R.id.name);
            cache.photoView = (QuickContactBadge) view.findViewById(R.id.badge);
            view.setTag(cache);

            return view;
        }
    }

newView方法中，生成Catch用存放通信录信息，nameView对应姓名，photoView对应图标
bindView方法中，将查询结果放入nameView和photoView中

效果如下