SearchableDictionary.java

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The file containing the source code shown below is located in the corresponding directory in <sdk>/samples/android-<version>/...

/*
 * Copyright (C) 2010 The Android开源工程
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.example.android.searchabledict;

import android.app.Activity;
import android.app.ActionBar;
import android.app.SearchManager;
import android.content.Context;
import android.content.Intent;
import android.database.Cursor;
import android.net.Uri;
import android.os.Build;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListView;
import android.widget.SearchView;
import android.widget.SimpleCursorAdapter;
import android.widget.TextView;
import android.widget.AdapterView.OnItemClickListener;

/**
 * The main activity for the dictionary.
 * Displays search results triggered by the search dialog and handles
 * actions from search suggestions.
 */
public class SearchableDictionary extends Activity {

    private TextView mTextView;
    private ListView mListView;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        mTextView = (TextView) findViewById(R.id.text);
        mListView = (ListView) findViewById(R.id.list);

        handleIntent(getIntent());
    }

    @Override
    protected void onNewIntent(Intent intent) {
        // Because this activity has set launchMode="singleTop", the system calls this method
        // to deliver the intent if this activity is currently the foreground activity when
        // invoked again (when the user executes a search from this activity, we don't create
        // a new instance of this activity, so the system delivers the search intent here)
        handleIntent(intent);
    }

    private void handleIntent(Intent intent) {
        if (Intent.ACTION_VIEW.equals(intent.getAction())) {
            // handles a click on a search suggestion; launches activity to show word
            Intent wordIntent = new Intent(this, WordActivity.class);
            wordIntent.setData(intent.getData());
            startActivity(wordIntent);
        } else if (Intent.ACTION_SEARCH.equals(intent.getAction())) {
            // handles a search query
            String query = intent.getStringExtra(SearchManager.QUERY);
            showResults(query);
        }
    }

    /**
     * Searches the dictionary and displays results for the given query.
     * @param query The search query
     */
    private void showResults(String query) {

        Cursor cursor = managedQuery(DictionaryProvider.CONTENT_URI, null, null,
                                new String[] {query}, null);

        if (cursor == null) {
            // There are no results
            mTextView.setText(getString(R.string.no_results, new Object[] {query}));
        } else {
            // Display the number of results
            int count = cursor.getCount();
            String countString = getResources().getQuantityString(R.plurals.search_results,
                                    count, new Object[] {count, query});
            mTextView.setText(countString);

            // Specify the columns we want to display in the result
            String[] from = new String[] { DictionaryDatabase.KEY_WORD,
                                           DictionaryDatabase.KEY_DEFINITION };

            // Specify the corresponding layout elements where we want the columns to go
            int[] to = new int[] { R.id.word,
                                   R.id.definition };

            // Create a simple cursor adapter for the definitions and apply them to the ListView
            SimpleCursorAdapter words = new SimpleCursorAdapter(this,
                                          R.layout.result, cursor, from, to);
            mListView.setAdapter(words);

            // Define the on-click listener for the list items
            mListView.setOnItemClickListener(new OnItemClickListener() {

                @Override
                public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                    // Build the Intent used to open WordActivity with a specific word Uri
                    Intent wordIntent = new Intent(getApplicationContext(), WordActivity.class);
                    Uri data = Uri.withAppendedPath(DictionaryProvider.CONTENT_URI,
                                                    String.valueOf(id));
                    wordIntent.setData(data);
                    startActivity(wordIntent);
                }
            });
        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        MenuInflater inflater = getMenuInflater();
        inflater.inflate(R.menu.options_menu, menu);

        if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB){
            SearchManager searchManager = (SearchManager) getSystemService(Context.SEARCH_SERVICE);
            SearchView searchView = (SearchView) menu.findItem(R.id.search).getActionView();
            searchView.setSearchableInfo(searchManager.getSearchableInfo(getComponentName()));
            searchView.setIconifiedByDefault(false);
        }

        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
            case R.id.search:
                onSearchRequested();
                return true;
            default:
                return false;
        }
    }
}