android.widget.CursorAdapter#FLAG_REGISTER_CONTENT_OBSERVER源码实例Demo

/**
 * 关注1
 * 模糊查询数据 & 显示到ListView列表上
 */
private void queryData(String tempName) {

    // 1. 模糊搜索
    Cursor cursor = helper.getReadableDatabase().rawQuery(
            "select id as _id,name from records where name like '%" + tempName + "%' order by id desc ", null);
    // 2. 创建adapter适配器对象 & 装入模糊搜索的结果
    adapter = new SimpleCursorAdapter(context, android.R.layout.simple_list_item_1, cursor, new String[] { "name" },
            new int[] { android.R.id.text1 }, CursorAdapter.FLAG_REGISTER_CONTENT_OBSERVER);
    // 3. 设置适配器
    listView.setAdapter(adapter);
    adapter.notifyDataSetChanged();

    System.out.println(cursor.getCount());
    // 当输入框为空 & 数据库中有搜索记录时，显示 "删除搜索记录"按钮
    if (tempName.equals("") && cursor.getCount() != 0){
        tv_clear.setVisibility(VISIBLE);
    }
    else {
        tv_clear.setVisibility(INVISIBLE);
    };

}
 

void init(final Cursor c, int flags) {
    if ((flags & CursorAdapter.FLAG_AUTO_REQUERY) == CursorAdapter.FLAG_AUTO_REQUERY) {
        flags |= CursorAdapter.FLAG_REGISTER_CONTENT_OBSERVER;
        mAutoRequery = true;
    } else {
        mAutoRequery = false;
    }
    boolean cursorPresent = c != null;
    mCursor = c;
    mDataValid = cursorPresent;
    mRowIDColumn = cursorPresent ? c.getColumnIndexOrThrow("_id") : -1;
    if ((flags & CursorAdapter.FLAG_REGISTER_CONTENT_OBSERVER) == CursorAdapter.FLAG_REGISTER_CONTENT_OBSERVER) {
        mChangeObserver = new ChangeObserver();
        mDataSetObserver = new MyDataSetObserver();
    } else {
        mChangeObserver = null;
        mDataSetObserver = null;
    }

    if (cursorPresent) {
        if (mChangeObserver != null) c.registerContentObserver(mChangeObserver);
        if (mDataSetObserver != null) c.registerDataSetObserver(mDataSetObserver);
    }
}
 

@Override
public void onActivityCreated(Bundle savedInstanceState) {
    super.onActivityCreated(savedInstanceState);
    mAdapter = new LyricCursorAdapter(getActivity(), R.layout.explorer_item,
            null, FROM, TO, CursorAdapter.FLAG_REGISTER_CONTENT_OBSERVER);
    mAdapter.setViewBinder(VIEW_BINDER);

    setListAdapter(mAdapter);

    // Done on a separate thread
    getLoaderManager().initLoader(LOADER_ID, null, this);

    registerForContextMenu(getListView());
    getListView().setTextFilterEnabled(true);
}
 

private void setUpPoemList() {
    shareListener = new OnShareClickListener();
    deleteListener = new OnDeleteClickListener();

    final ListView poemsList = (ListView) findViewById(R.id.poem_history_list);

    adapter = new PoemCursorAdapter(
            getApplicationContext(),
            null,
            CursorAdapter.FLAG_REGISTER_CONTENT_OBSERVER);

    // MoPub integration
    final ViewBinder mopubViewBinder = new ViewBinder.Builder(R.layout.native_ad_layout)
            .mainImageId(R.id.native_ad_main_image)
            .iconImageId(R.id.native_ad_icon_image)
            .titleId(R.id.native_ad_title)
            .textId(R.id.native_ad_text)
            .build();

    MoPubNativeAdPositioning.MoPubServerPositioning adPositioning =
            MoPubNativeAdPositioning.serverPositioning();
    final MoPubNativeAdRenderer adRenderer = new MoPubNativeAdRenderer(mopubViewBinder);
    moPubAdAdapter = new MoPubAdAdapter(this, adapter, adPositioning);
    moPubAdAdapter.registerAdRenderer(adRenderer);

    poemsList.setAdapter(moPubAdAdapter);
}
 

@Override
protected void onCreate(Bundle savedInstanceState) {
	super.onCreate(savedInstanceState);
	setContentView(R.layout.session_manager_activity);
	mListViewSessions = (ListView) findViewById(R.id.listViewSessions);
	getLoaderManager().initLoader(0, null,
			new SessionLoaderCallbacks());
	mAdapter = new SimpleCursorAdapter(this, R.layout.session_list_row,
			null, FROM, TO, CursorAdapter.FLAG_REGISTER_CONTENT_OBSERVER);
	mAdapter.setViewBinder(new SessionViewBinder());
	mListViewSessions.setAdapter(mAdapter);
	mListViewSessions
			.setOnItemClickListener(new SessionOnItemClickListener());
	registerForContextMenu(mListViewSessions);
}