add next and previous buttons on InstaPaper Viewer

Author: Arnav Gupta

App/src/main/java/in/ac/dtu/subtlenews/InstapaperViewer.java

@@ -4,6 +4,7 @@
 
 import android.annotation.TargetApi;
 import android.app.Activity;
+import android.content.DialogInterface;
 import android.content.Intent;
 import android.os.Build;
 import android.os.Bundle;
@@ -13,9 +14,15 @@
 import android.view.MenuItem;
 import android.support.v4.app.NavUtils;
 import android.webkit.WebView;
+import android.widget.Button;
 import android.widget.FrameLayout;
 import android.widget.LinearLayout;
 
+import org.json.JSONException;
+import org.json.JSONObject;
+
+import java.util.ArrayList;
+
 /**
  * An example full-screen activity that shows and hides the system UI (i.e.
  * status bar and navigation/system bar) with user interaction.
@@ -24,6 +31,9 @@
  */
 public class InstapaperViewer extends Activity {
     public String summaryUrl = "http://google.com";
+    public Integer urlId = 0;
+    public ArrayList<String> urlList;
+
 
     /**
      * Whether or not the system UI should be auto-hidden after
@@ -62,13 +72,18 @@ protected void onCreate(Bundle savedInstanceState) {
 
         Bundle extras = getIntent().getExtras();
         if (extras != null) {
-            summaryUrl = extras.getString("URL");
+            urlId = extras.getInt("URLID");
+            urlList = extras.getStringArrayList("URLList");
+
         }
         final WebView instapaperView = (WebView) findViewById(R.id.instapaper_viewer);
 
         final View controlsView = findViewById(R.id.fullscreen_content_controls);
         final View contentView = findViewById(R.id.instapaper_viewer);
 
+        final Button prevButton = (Button) findViewById(R.id.summary_prev_button);
+        final Button nextButton = (Button) findViewById(R.id.summary_next_button);
+
         // Set up an instance of SystemUiHider to control the system UI for
         // this activity.
         mSystemUiHider = SystemUiHider.getInstance(this, contentView, HIDER_FLAGS);
@@ -135,10 +150,38 @@ public void onClick(View view) {
         // Upon interacting with UI controls, delay any scheduled hide()
         // operations to prevent the jarring behavior of controls going away
         // while interacting with the UI.
-        findViewById(R.id.summary_back_button).setOnTouchListener(mDelayHideTouchListener);
-
+        prevButton.setOnTouchListener(mDelayHideTouchListener);
+        nextButton.setOnTouchListener(mDelayHideTouchListener);
 
+        try {
+            summaryUrl = "http://www.instapaper.com/text?u=" + urlList.get(urlId);
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
         instapaperView.loadUrl(summaryUrl);
+        prevButton.setOnClickListener(new View.OnClickListener() {
+            @Override
+            public void onClick(View view) {
+                try {
+                    summaryUrl = "http://www.instapaper.com/text?u=" + urlList.get(--urlId);
+                } catch (Exception e) {
+                    e.printStackTrace();
+                }
+                instapaperView.loadUrl(summaryUrl);
+            }
+        });
+        nextButton.setOnClickListener(new View.OnClickListener() {
+            @Override
+            public void onClick(View view) {
+                try {
+                    summaryUrl = "http://www.instapaper.com/text?u=" + urlList.get(++urlId);
+                } catch (Exception e) {
+                    e.printStackTrace();
+                }
+                instapaperView.loadUrl(summaryUrl);
+            }
+        });
+
     }
 
     @Override

App/src/main/java/in/ac/dtu/subtlenews/MainFragment.java

@@ -48,6 +48,7 @@ public class MainFragment extends Fragment {
     private static final String TAG = "MAIN_FRAGMENT";
 
     private int sNumber ;
+    public ArrayList<String> urlArray = new ArrayList<String>();
 
     View rootView;
 
@@ -130,6 +131,7 @@ protected ArrayList<JSONObject> doInBackground(Void... v) {
 
                     if(obj.getString("category").equals(Utils.categoryMap[sNumber - 1])){
                         selectedCategoryList.add(obj);
+                        urlArray.add(obj.getString(TAG_LINK));
                     }
 
                 }
@@ -169,22 +171,12 @@ public void onItemClick(AdapterView<?> adapterView, View view, final int i, long
                                 .setMessage(fArrayList.get(i).getString(TAG_SUMMARY))
                                 .setPositiveButton("Instapaper", new DialogInterface.OnClickListener() {
                                     public void onClick(DialogInterface dialog, int id) {
-                                        /* TODO :
-                                            USE webview to implement in-app browser instead of this
 
 
-                                        Intent browserIntent = new Intent(Intent.ACTION_VIEW, Uri.parse(url));
-                                        startActivity(browserIntent);
-                                        */
-                                        String url = "http://www.google.com";
-                                        try {
-                                            url = "http://www.instapaper.com/text?u=" + fArrayList.get(i).getString(TAG_LINK);
-                                        } catch (JSONException e) {
-                                            e.printStackTrace();
-                                        }
 
                                         Intent instapaper = new Intent(getActivity(), InstapaperViewer.class);
-                                        instapaper.putExtra("URL", url);
+                                        instapaper.putExtra("URLID", i);
+                                        instapaper.putExtra("URLList", urlArray);
                                         startActivity(instapaper);
 
 

App/src/main/res/layout/activity_instapaper_viewer.xml

@@ -29,12 +29,18 @@
             android:orientation="horizontal"
             tools:ignore="UselessParent">
 
-            <Button android:id="@+id/summary_back_button"
+            <Button android:id="@+id/summary_prev_button"
                 style="?metaButtonBarButtonStyle"
                 android:layout_width="0dp"
                 android:layout_height="wrap_content"
                 android:layout_weight="1"
-                android:text="@string/summary_back_button" />
+                android:text="@string/summary_prev_button" />
+            <Button android:id="@+id/summary_next_button"
+                style="?metaButtonBarButtonStyle"
+                android:layout_width="0dp"
+                android:layout_height="wrap_content"
+                android:layout_weight="1"
+                android:text="@string/summary_next_button" />
 
         </LinearLayout>
     </FrameLayout>

App/src/main/res/values/strings.xml

@@ -14,5 +14,7 @@
     <string name="title_activity_instapaper_viewer">InstapaperViewer</string>
     <string name="summary_back_button">Back</string>
     <string name="dummy_content">DUMMY\nCONTENT</string>
+    <string name="summary_next_button">Next</string>
+    <string name="summary_prev_button">Prev</string>
 
 </resources>