Android : 06-Notifications: add

1 files changed, 235 insertions, 0 deletions

diff --git a/Android/06-Notifications/Notifications/src/course/labs/notificationslab/MainActivity.java b/Android/06-Notifications/Notifications/src/course/labs/notificationslab/MainActivity.java
new file mode 100644
index 0000000..eebf924
--- /dev/null
+++ b/Android/06-Notifications/Notifications/src/course/labs/notificationslab/MainActivity.java
@@ -0,0 +1,235 @@
+package course.labs.notificationslab;
+
+import java.io.BufferedReader;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.io.InputStreamReader;
+
+import org.json.JSONArray;
+import org.json.JSONException;
+import org.json.JSONObject;
+
+import android.app.Activity;
+import android.app.FragmentManager;
+import android.app.FragmentTransaction;
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.os.Bundle;
+import android.util.Log;
+
+public class MainActivity extends Activity implements SelectionListener {
+
+    public static final String TWEET_FILENAME = "tweets.txt";
+    public static final String[] FRIENDS = { "taylorswift13", "msrebeccablack", "ladygaga" };
+    public static final String DATA_REFRESHED_ACTION = "course.labs.notificationslab.DATA_REFRESHED";
+
+    private static final int NUM_FRIENDS = 3;
+    private static final String URL_LGAGA = "https://d396qusza40orc.cloudfront.net/android%2FLabs%2FUserNotifications%2Fladygaga.txt";
+    private static final String URL_RBLACK = "https://d396qusza40orc.cloudfront.net/android%2FLabs%2FUserNotifications%2Frebeccablack.txt";
+    private static final String URL_TSWIFT = "https://d396qusza40orc.cloudfront.net/android%2FLabs%2FUserNotifications%2Ftaylorswift.txt";
+    private static final String TAG = "Lab-Notifications";
+    private static final long TWO_MIN = 2 * 60 * 1000;
+    private static final int UNSELECTED = -1;
+
+    private FragmentManager mFragmentManager;
+    private FriendsFragment mFriendsFragment;
+    private boolean mIsFresh;
+    private BroadcastReceiver mRefreshReceiver;
+    private int mFeedSelected = UNSELECTED;
+    private FeedFragment mFeedFragment;
+    private String[] mRawFeeds = new String[3];
+    private String[] mProcessedFeeds = new String[3];
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.activity_main);
+        mFragmentManager = getFragmentManager();
+        addFriendsFragment();
+        // The feed is fresh if it was downloaded less than 2 minutes ago
+        mIsFresh = (System.currentTimeMillis() - getFileStreamPath( TWEET_FILENAME).lastModified()) < TWO_MIN;
+        ensureData();
+    }
+
+    // Add Friends Fragment to Activity
+    private void addFriendsFragment() {
+        mFriendsFragment = new FriendsFragment();
+        mFriendsFragment.setArguments(getIntent().getExtras());
+        FragmentTransaction transaction = mFragmentManager.beginTransaction();
+        transaction.add(R.id.fragment_container, mFriendsFragment);
+        transaction.commit();
+    }
+
+    // If stored Tweets are not fresh, reload them from network
+    // Otherwise, load them from file
+    private void ensureData() {
+
+        log("In ensureData(), mIsFresh:" + mIsFresh);
+
+        if (!mIsFresh) {
+            // TODO:
+            // Show a Toast Notification to inform user that
+            // the app is "Downloading Tweets from Network"
+            log ("Issuing Toast Message");
+
+            // TODO:
+            // Start new AsyncTask to download Tweets from network
+
+            // Set up a BroadcastReceiver to receive an Intent when download
+            // finishes.
+            mRefreshReceiver = new BroadcastReceiver() {
+                @Override
+                public void onReceive(Context context, Intent intent) {
+                    log("BroadcastIntent received in MainActivity");
+                    // TODO:
+                    // Check to make sure this is an ordered broadcast
+                    // Let sender know that the Intent was received
+                    // by setting result code to RESULT_OK
+                }
+            };
+        } else {
+            loadTweetsFromFile();
+            parseJSON();
+            updateFeed();
+        }
+    }
+
+    // Called when new Tweets have been downloaded
+    public void setRefreshed(String[] feeds) {
+        mRawFeeds[0] = feeds[0];
+        mRawFeeds[1] = feeds[1];
+        mRawFeeds[2] = feeds[2];
+
+        parseJSON();
+        updateFeed();
+        mIsFresh = true;
+    };
+
+    // Called when a Friend is clicked on
+    @Override
+    public void onItemSelected(int position) {
+        mFeedSelected = position;
+        mFeedFragment = addFeedFragment();
+
+        if (mIsFresh) {
+            updateFeed();
+        }
+    }
+
+    // Calls FeedFragement.update, passing in the
+    // the tweets for the currently selected friend
+    void updateFeed() {
+        if (null != mFeedFragment)
+            mFeedFragment.update(mProcessedFeeds[mFeedSelected]);
+    }
+
+    // Add FeedFragment to Activity
+    private FeedFragment addFeedFragment() {
+        FeedFragment feedFragment;
+        feedFragment = new FeedFragment();
+
+        FragmentTransaction transaction = mFragmentManager.beginTransaction();
+
+        transaction.replace(R.id.fragment_container, feedFragment);
+        transaction.addToBackStack(null);
+
+        transaction.commit();
+        mFragmentManager.executePendingTransactions();
+        return feedFragment;
+    }
+
+    // Register the BroadcastReceiver
+    @Override
+    protected void onResume() {
+        super.onResume();
+        // TODO:
+        // Register the BroadcastReceiver to receive a
+        // DATA_REFRESHED_ACTION broadcast
+    }
+
+    @Override
+    protected void onPause() {
+        // TODO:
+        // Unregister the BroadcastReceiver
+        super.onPause();
+    }
+
+    // Convert raw Tweet data (in JSON format) into text for display
+    public void parseJSON() {
+
+        JSONArray[] JSONFeeds = new JSONArray[NUM_FRIENDS];
+
+        for (int i = 0; i < NUM_FRIENDS; i++) {
+            try {
+                JSONFeeds[i] = new JSONArray(mRawFeeds[i]);
+            } catch (JSONException e) {
+                e.printStackTrace();
+            }
+
+            String name = "";
+            String tweet = "";
+
+            JSONArray tmp = JSONFeeds[i];
+
+            // string buffer for twitter feeds
+            StringBuffer tweetRec = new StringBuffer("");
+
+            for (int j = 0; j < tmp.length(); j++) {
+                try {
+                    tweet = tmp.getJSONObject(j).getString("text");
+                    JSONObject user = (JSONObject) tmp.getJSONObject(j).get(
+                            "user");
+                    name = user.getString("name");
+
+                } catch (JSONException e) {
+                    e.printStackTrace();
+                }
+
+                tweetRec.append(name + " - " + tweet + "\n\n");
+            }
+            mProcessedFeeds[i] = tweetRec.toString();
+        }
+    }
+
+    // Retrieve feeds text from a file
+    // Store them in mRawTextFeed[]
+    private void loadTweetsFromFile() {
+        BufferedReader reader = null;
+
+        try {
+            FileInputStream fis = openFileInput(TWEET_FILENAME);
+            reader = new BufferedReader(new InputStreamReader(fis));
+            String s = null;
+            int i = 0;
+            while (null != (s = reader.readLine()) && i < NUM_FRIENDS) {
+                mRawFeeds[i] = s;
+                i++;
+            }
+        } catch (FileNotFoundException e) {
+            e.printStackTrace();
+        } catch (IOException e) {
+            e.printStackTrace();
+        } finally {
+            if (null != reader) {
+                try {
+                    reader.close();
+                } catch (IOException e) {
+                    e.printStackTrace();
+                }
+            }
+        }
+    }
+
+    // Simplified log output method
+    private void log(String msg) {
+        try {
+            Thread.sleep(500);
+        } catch (InterruptedException e) {
+            e.printStackTrace();
+        }
+        Log.i(TAG, msg);
+    }
+}