Android:提供最近的搜索建议而没有可搜索的活动？

Question

我有一个ActionBar SearchView,我成功地用它进行搜索.android文档没有解释如何实现搜索建议.我不想进行可搜索的活动.

这是我的搜索代码:

public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.activity_add_song, menu);
        final SearchView searchView = (SearchView) menu.findItem(R.id.song_search).getActionView();
        searchView.setFocusable(true);
        searchView.setIconified(false);
        final AddSongActivity activity = this;
        searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
            @Override
            public boolean onQueryTextChange(String newText) {
                // Do nothing
                return true;
            }

            @Override
            public boolean onQueryTextSubmit(String query) {
                // Clear SearchView
                searchView.clearFocus();
                // Begin Spotify Search
                TextView notice = (TextView)findViewById(R.id.search_notice);
                URL url;
                try {
                    url = new URL("http://ws.spotify.com/search/1/track.json?q=" + URLEncoder.encode(query,"UTF-8"));
                } catch (MalformedURLException e) {
                    notice.setText("Malformed Search");
                    notice.setHeight(noticeHeight);
                    return true;
                } catch (UnsupportedEncodingException e) {
                    notice.setText("Unsupported Encoding. Maybe a problem with your device.");
                    notice.setHeight(noticeHeight);
                    return true;
                }
                new SearchDownload(url, activity).execute();
                notice.setText("Loading Tracks");
                notice.setHeight(noticeHeight);
                Log.i("infodb","" + noticeHeight);
                return true;
            }
        });

这适用于搜索,但我不知道实现最近的搜索查询建议.我该怎么做呢？

谢谢.

Answer 1

好的,我把时间花在了这上面.我自己做了一个简单的建议实现SQLiteDatabase.

我们将创建3个类,如下所示

1. MainActivity- 用于测试SearchView数据库的建议
2. SuggestionDatabase - 这将存储您最近的搜索关键字.
3. SuggestionSimpleCursorAdapter- 这是一个子类SimpleCursorAdapter.我将解释为什么我创建这个课而不是使用SimpleCursorAdapter.

代码

// MainActivity.java

public class MainActivity 
    extends Activity
    implements SearchView.OnQueryTextListener,
                SearchView.OnSuggestionListener
{

    private SuggestionsDatabase database;
    private SearchView searchView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);


        database = new SuggestionsDatabase(this);
        searchView = (SearchView) findViewById(R.id.searchView1);
        searchView.setOnQueryTextListener(this); 
        searchView.setOnSuggestionListener(this);
    }

    @Override
    public boolean onSuggestionSelect(int position) {

        return false;
    }

    @Override
    public boolean onSuggestionClick(int position) {

        SQLiteCursor cursor = (SQLiteCursor) searchView.getSuggestionsAdapter().getItem(position);
        int indexColumnSuggestion = cursor.getColumnIndex( SuggestionsDatabase.FIELD_SUGGESTION);

        searchView.setQuery(cursor.getString(indexColumnSuggestion), false);

        return true;
    }

    @Override
    public boolean onQueryTextSubmit(String query) {
        long result = database.insertSuggestion(query);
        return result != -1;
    }

    @Override
    public boolean onQueryTextChange(String newText) {

        Cursor cursor = database.getSuggestions(newText);
        if(cursor.getCount() != 0)
        {
            String[] columns = new String[] {SuggestionsDatabase.FIELD_SUGGESTION };
            int[] columnTextId = new int[] { android.R.id.text1};

            SuggestionSimpleCursorAdapter simple = new SuggestionSimpleCursorAdapter(getBaseContext(),
                    android.R.layout.simple_list_item_1, cursor,
                    columns , columnTextId
                    , 0);

            searchView.setSuggestionsAdapter(simple);
            return true;
        }
        else
        {
            return false;
        }
    }

}

这个怎么运作

1. 当用户点击搜索按钮时,onQueryTextSubmit()将触发该搜索按钮,然后搜索关键字将保存在我们的数据库中.假设我们提交了一个关键字"Hello"
2. 如果用户在例如将一个字符串"赫尔"或"H" SearchView的onQueryTextChange()将被调用,然后我们在搜索这个关键字SQLiteDatabase(SuggestionDatabase).如果"Hel"或"H"匹配"Hello",则通过设置返回的Cursor来显示查询结果,SuggestionSimpleCursorAdapter然后将此适配器设置为SearchView.这是图片.

3.当然,我们将点击"Hello"的建议,onSuggestionClick(int position)将被要求.我们SQLiteCursor从SearchView适配器(SuggestionSimpleCursorAdapter)获取对象并从中获取Suggestion文本,在SearchView对象中设置建议文本

SQLiteCursor cursor = (SQLiteCursor) searchView.getSuggestionsAdapter().getItem(position);
int indexColumnSuggestion = cursor.getColumnIndex( SuggestionsDatabase.FIELD_SUGGESTION);
searchView.setQuery(cursor.getString(indexColumnSuggestion), false);

如果我们使用SimpleCursorAdapter它也可以正常工作但我们说我们有这种情况

1. 如果我们在智能手机中运行此程序并键入关键字"Hel",则建议将正确显示.

2. 如果我们在横向旋转屏幕怎么办？它将切换到全屏模式,您仍然可以键入关键字.

建议会发生什么？让我们来看看.

看到奇怪的建议？我们如何解决？通过覆盖convertToString(Cursor cursor)返回aCharSequence

 // SuggestionSimpleCursorAdapter.java
public class SuggestionSimpleCursorAdapter
    extends SimpleCursorAdapter
{

    public SuggestionSimpleCursorAdapter(Context context, int layout, Cursor c,
            String[] from, int[] to) {
        super(context, layout, c, from, to);
    }

    public SuggestionSimpleCursorAdapter(Context context, int layout, Cursor c,
            String[] from, int[] to, int flags) {
        super(context, layout, c, from, to, flags);
    }

    @Override
    public CharSequence convertToString(Cursor cursor) {

        int indexColumnSuggestion = cursor.getColumnIndex(SuggestionsDatabase.FIELD_SUGGESTION);

        return cursor.getString(indexColumnSuggestion);
    }


}

通过覆盖convertToString(Cursor cursor),这是结果

这是数据库

// SuggestionDatabase.java
public class SuggestionsDatabase {

  public static final String DB_SUGGESTION = "SUGGESTION_DB";
  public final static String TABLE_SUGGESTION = "SUGGESTION_TB";
  public final static String FIELD_ID = "_id";
  public final static String FIELD_SUGGESTION = "suggestion";

  private SQLiteDatabase db;
  private Helper helper;

  public SuggestionsDatabase(Context context) {

    helper = new Helper(context, DB_SUGGESTION, null, 1);
    db = helper.getWritableDatabase();
  }

  public long insertSuggestion(String text)
  {
    ContentValues values = new ContentValues();
    values.put(FIELD_SUGGESTION, text);
    return db.insert(TABLE_SUGGESTION, null, values);
  }

  public Cursor getSuggestions(String text)
  {
    return db.query(TABLE_SUGGESTION, new String[] {FIELD_ID, FIELD_SUGGESTION}, 
            FIELD_SUGGESTION+" LIKE '"+ text +"%'", null, null, null, null);
  }


    private class Helper extends SQLiteOpenHelper
    {

    public Helper(Context context, String name, CursorFactory factory,
            int version) {
        super(context, name, factory, version);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        db.execSQL("CREATE TABLE "+TABLE_SUGGESTION+" ("+
                    FIELD_ID+" integer primary key autoincrement, "+FIELD_SUGGESTION+" text);");
        Log.d("SUGGESTION", "DB CREATED");
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

    }

  }

}

我希望这个答案对其他程序员很有用.:)

Answer 2

我的需求更加简单 - 我不需要数据库,因为我有很多想要显示的建议包含在ArrayList中.

这是一个示例实现:

import java.util.ArrayList;

import android.app.Activity;
import android.app.SearchManager;
import android.content.Context;
import android.database.Cursor;
import android.database.MatrixCursor;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.CursorAdapter;
import android.widget.SearchView;
import android.widget.SearchView.OnQueryTextListener;
import android.widget.TextView;
import android.widget.Toast;

public class ActivityTest extends Activity implements OnQueryTextListener {

    private static final String COLUMN_ID = "_id";
    private static final String COLUMN_TERM = "term";
    private static final String DEFAULT = "default";

    private SearchManager searchManager;
    private SearchView searchView;
    private MenuItem searchMenuItem;
    private SuggestAdapter suggestionsAdapter;
    private final ArrayList<String> suggestionsArray = new ArrayList<String>();
    private final ArrayList<String> dummyArray = new ArrayList<String>();

    @Override
    protected void onCreate(final Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        // Create some dummy entries
        dummyArray.add("apples");
        dummyArray.add("oranges");
        dummyArray.add("bananas");
        dummyArray.add("pears");
        dummyArray.add("plums");

    }

    @Override
    public boolean onCreateOptionsMenu(final Menu menu) {
        getMenuInflater().inflate(R.menu.main, menu);

        searchManager = (SearchManager) getSystemService(Context.SEARCH_SERVICE);
        searchMenuItem = menu.findItem(R.id.action_search);

        searchView = (SearchView) searchMenuItem.getActionView();
        searchView.setSearchableInfo(searchManager.getSearchableInfo(getComponentName()));
        searchView.setOnQueryTextListener(this);

        final MatrixCursor matrixCursor = getCursor(suggestionsArray);
        suggestionsAdapter = new SuggestAdapter(this, matrixCursor, suggestionsArray);
        searchView.setSuggestionsAdapter(suggestionsAdapter);
        suggestionsAdapter.notifyDataSetChanged();

        return true;
    }

    @Override
    public boolean onQueryTextChange(final String newText) {

        suggestionsArray.clear();

        for (int i = 0; i < dummyArray.size(); i++) {

            if (dummyArray.get(i).contains(newText)) {
                suggestionsArray.add(dummyArray.get(i));
            }
        }

        final MatrixCursor matrixCursor = getCursor(suggestionsArray);
        suggestionsAdapter = new SuggestAdapter(this, matrixCursor, suggestionsArray);
        searchView.setSuggestionsAdapter(suggestionsAdapter);
        suggestionsAdapter.notifyDataSetChanged();

        return true;
    }

    @Override
    public boolean onQueryTextSubmit(final String query) {
        // TODO Auto-generated method stub
        return false;
    }

    private class SuggestAdapter extends CursorAdapter implements OnClickListener {

        private final ArrayList<String> mObjects;
        private final LayoutInflater mInflater;
        private TextView tvSearchTerm;

        public SuggestAdapter(final Context ctx, final Cursor cursor, final ArrayList<String> mObjects) {
            super(ctx, cursor, 0);

            this.mObjects = mObjects;
            this.mInflater = (LayoutInflater) ctx.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        }

        @Override
        public View newView(final Context ctx, final Cursor cursor, final ViewGroup parent) {
            final View view = mInflater.inflate(R.layout.list_item_search, parent, false);

            tvSearchTerm = (TextView) view.findViewById(R.id.tvSearchTerm);

            return view;
        }

        @Override
        public void bindView(final View view, final Context ctx, final Cursor cursor) {

            tvSearchTerm = (TextView) view.findViewById(R.id.tvSearchTerm);

            final int position = cursor.getPosition();

            if (cursorInBounds(position)) {

                final String term = mObjects.get(position);
                tvSearchTerm.setText(term);

                view.setTag(position);
                view.setOnClickListener(this);

            } else {
                // Something went wrong
            }
        }

        private boolean cursorInBounds(final int position) {
            return position < mObjects.size();
        }

        @Override
        public void onClick(final View view) {

            final int position = (Integer) view.getTag();

            if (cursorInBounds(position)) {

                final String selected = mObjects.get(position);

                Toast.makeText(getApplicationContext(), selected, Toast.LENGTH_SHORT).show();

                // Do something

            } else {
                // Something went wrong
            }
        }
    }

    private MatrixCursor getCursor(final ArrayList<String> suggestions) {

        final String[] columns = new String[] { COLUMN_ID, COLUMN_TERM };
        final Object[] object = new Object[] { 0, DEFAULT };

        final MatrixCursor matrixCursor = new MatrixCursor(columns);

        for (int i = 0; i < suggestions.size(); i++) {

            object[0] = i;
            object[1] = suggestions.get(i);

            matrixCursor.addRow(object);
        }

        return matrixCursor;
    }
}

在我的实际代码中,我有一个自定义接口,它使用从服务器获取的动态术语填充ArrayList.您将以这种方式更新数据集:

@Override
public void onDataReceived(final ArrayList<String> results) {

    suggestionsArray.clear();
    suggestionsArray.addAll(results);

    final MatrixCursor matrixCursor = getCursor(suggestionsArray);
    suggestionsAdapter = new SuggestAdapter(this, matrixCursor, suggestionsArray);
    searchView.setSuggestionsAdapter(suggestionsAdapter);
    suggestionsAdapter.notifyDataSetChanged();
} 

我发现没有初始化空光标或每次重新创建它都会导致问题.

希望能帮助到你.