samples/training/ContactsList/src/com/example/android/contactslist/ui/ContactsListActivity.java

/*
 * Copyright (C) 2013 The Android Open Source Project
 *
 * 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.contactslist.ui;

import android.app.SearchManager;
import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;

import com.example.android.contactslist.BuildConfig;
import com.example.android.contactslist.R;
import com.example.android.contactslist.util.Utils;

/**
 * FragmentActivity to hold the main {@link ContactsListFragment}. On larger screen devices which
 * can fit two panes also load {@link ContactDetailFragment}.
 */
public class ContactsListActivity extends FragmentActivity implements
        ContactsListFragment.OnContactsInteractionListener {

    // Defines a tag for identifying log entries
    private static final String TAG = "ContactsListActivity";

    private ContactDetailFragment mContactDetailFragment;

    // If true, this is a larger screen device which fits two panes
    private boolean isTwoPaneLayout;

    // True if this activity instance is a search result view (used on pre-HC devices that load
    // search results in a separate instance of the activity rather than loading results in-line
    // as the query is typed.
    private boolean isSearchResultView = false;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        if (BuildConfig.DEBUG) {
            Utils.enableStrictMode();
        }
        super.onCreate(savedInstanceState);

        // Set main content view. On smaller screen devices this is a single pane view with one
        // fragment. One larger screen devices this is a two pane view with two fragments.
        setContentView(R.layout.activity_main);

        // Check if two pane bool is set based on resource directories
        isTwoPaneLayout = getResources().getBoolean(R.bool.has_two_panes);

        // Check if this activity instance has been triggered as a result of a search query. This
        // will only happen on pre-HC OS versions as from HC onward search is carried out using
        // an ActionBar SearchView which carries out the search in-line without loading a new
        // Activity.
        if (Intent.ACTION_SEARCH.equals(getIntent().getAction())) {

            // Fetch query from intent and notify the fragment that it should display search
            // results instead of all contacts.
            String searchQuery = getIntent().getStringExtra(SearchManager.QUERY);
            ContactsListFragment mContactsListFragment = (ContactsListFragment)
                    getSupportFragmentManager().findFragmentById(R.id.contact_list);

            // This flag notes that the Activity is doing a search, and so the result will be
            // search results rather than all contacts. This prevents the Activity and Fragment
            // from trying to a search on search results.
            isSearchResultView = true;
            mContactsListFragment.setSearchQuery(searchQuery);

            // Set special title for search results
            String title = getString(R.string.contacts_list_search_results_title, searchQuery);
            setTitle(title);
        }

        if (isTwoPaneLayout) {
            // If two pane layout, locate the contact detail fragment
            mContactDetailFragment = (ContactDetailFragment)
                    getSupportFragmentManager().findFragmentById(R.id.contact_detail);
        }
    }

    /**
     * This interface callback lets the main contacts list fragment notify
     * this activity that a contact has been selected.
     *
     * @param contactUri The contact Uri to the selected contact.
     */
    @Override
    public void onContactSelected(Uri contactUri) {
        if (isTwoPaneLayout && mContactDetailFragment != null) {
            // If two pane layout then update the detail fragment to show the selected contact
            mContactDetailFragment.setContact(contactUri);
        } else {
            // Otherwise single pane layout, start a new ContactDetailActivity with
            // the contact Uri
            Intent intent = new Intent(this, ContactDetailActivity.class);
            intent.setData(contactUri);
            startActivity(intent);
        }
    }

    /**
     * This interface callback lets the main contacts list fragment notify
     * this activity that a contact is no longer selected.
     */
    @Override
    public void onSelectionCleared() {
        if (isTwoPaneLayout && mContactDetailFragment != null) {
            mContactDetailFragment.setContact(null);
        }
    }

    @Override
    public boolean onSearchRequested() {
        // Don't allow another search if this activity instance is already showing
        // search results. Only used pre-HC.
        return !isSearchResultView && super.onSearchRequested();
    }
}