[tx-robot] updated from transifex
[pub/Android/ownCloud.git] / src / com / owncloud / android / ui / fragment / ShareFileFragment.java
index ee979c6..46382a6 100644 (file)
@@ -33,7 +33,9 @@ import android.view.ViewGroup;
 import android.widget.Button;
 import android.widget.CompoundButton;
 import android.widget.ImageView;
+import android.widget.ListAdapter;
 import android.widget.ListView;
+import android.widget.ScrollView;
 import android.widget.Switch;
 import android.widget.TextView;
 import android.widget.Toast;
@@ -45,12 +47,17 @@ import com.owncloud.android.datamodel.ThumbnailsCacheManager;
 import com.owncloud.android.lib.common.utils.Log_OC;
 import com.owncloud.android.lib.resources.shares.OCShare;
 import com.owncloud.android.lib.resources.shares.ShareType;
+import com.owncloud.android.lib.resources.status.OCCapability;
 import com.owncloud.android.ui.activity.FileActivity;
 import com.owncloud.android.ui.adapter.ShareUserListAdapter;
+import com.owncloud.android.ui.dialog.ExpirationDatePickerDialogFragment;
 import com.owncloud.android.utils.DisplayUtils;
 import com.owncloud.android.utils.MimetypeIconUtil;
 
+import java.text.SimpleDateFormat;
+
 import java.util.ArrayList;
+import java.util.Date;
 
 /**
  * Fragment for Sharing a file with sharees (users or groups) or creating
@@ -70,10 +77,13 @@ public class ShareFileFragment extends Fragment
 
     private static final String TAG = ShareFileFragment.class.getSimpleName();
 
-    // the fragment initialization parameters
+    /** The fragment initialization parameters */
     private static final String ARG_FILE = "FILE";
     private static final String ARG_ACCOUNT = "ACCOUNT";
 
+//    /** Tag for dialog */
+//    private static final String FTAG_CHOOSER_DIALOG = "CHOOSER_DIALOG";
+
     /** File to share, received as a parameter in construction time */
     private OCFile mFile;
 
@@ -86,12 +96,28 @@ public class ShareFileFragment extends Fragment
     /** List of private shares bound to the file */
     private ArrayList<OCShare> mPrivateShares;
 
+    /** Capabilities of the server */
+    private OCCapability mCapabilities;
+
     /** Adapter to show private shares */
     private ShareUserListAdapter mUserGroupsAdapter = null;
 
     /** Public share bound to the file */
     private OCShare mPublicShare;
 
+    /** Listener for changes on switch to share / unshare publicly */
+    private CompoundButton.OnCheckedChangeListener mOnShareViaLinkSwitchCheckedChangeListener;
+
+    /**
+     * Listener for user actions to set, update or clear password on public link
+     */
+    private OnPasswordInteractionListener mOnPasswordInteractionListener = null;
+
+    /**
+     * Listener for user actions to set, update or clear expiration date on public link
+     */
+    private OnExpirationDateInteractionListener mOnExpirationDateInteractionListener = null;
+
 
     /**
      * Public factory method to create new ShareFileFragment instances.
@@ -119,18 +145,22 @@ public class ShareFileFragment extends Fragment
     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
+        Log_OC.d(TAG, "onCreate");
         if (getArguments() != null) {
             mFile = getArguments().getParcelable(ARG_FILE);
             mAccount = getArguments().getParcelable(ARG_ACCOUNT);
         }
     }
 
+
     /**
      * {@inheritDoc}
      */
     @Override
     public View onCreateView(LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
+        Log_OC.d(TAG, "onCreateView");
+
         // Inflate the layout for this fragment
         View view = inflater.inflate(R.layout.share_file_layout, container, false);
 
@@ -175,70 +205,246 @@ public class ShareFileFragment extends Fragment
         });
 
         // Switch to create public share
-        Switch shareViaLinkSwitch = (Switch) view.findViewById(R.id.shareViaLinkSectionSwitch);
-        shareViaLinkSwitch.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
+        mOnShareViaLinkSwitchCheckedChangeListener = new CompoundButton.OnCheckedChangeListener() {
             @Override
-            public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
-                if (isChecked) {
-                    // TODO real implementation: create public share
-                    // expand section
-                    getExpirationDateSection().setVisibility(View.VISIBLE);
-                    getPasswordSection().setVisibility(View.VISIBLE);
-                    getGetLinkButton().setVisibility(View.VISIBLE);
+            public void onCheckedChanged(CompoundButton switchView, boolean isChecked) {
+            }
+        };
+
+        // Set listener for user actions on switch for sharing/unsharing via link
+        initShareViaLinkListener(view);
+
+        // Set listener for user actions on expiration date
+        initExpirationListener(view);
+
+        // Set listener for user actions on password
+        initPasswordListener(view);
+
+        return view;
+    }
+
+
+    /**
+     * Binds listener for user actions to create or delete a public share
+     * to the views receiving the user events.
+     *
+     * @param shareView     Root view in the fragment.
+     */
+    private void initShareViaLinkListener(View shareView) {
+        mOnShareViaLinkSwitchCheckedChangeListener = new OnShareViaLinkListener();
+        Switch shareViaLinkSwitch = (Switch) shareView.findViewById(R.id.shareViaLinkSectionSwitch);
+        shareViaLinkSwitch.setOnCheckedChangeListener(mOnShareViaLinkSwitchCheckedChangeListener);
+    }
+
+    /**
+     * Listener for user actions that create or delete a public share.
+     */
+    private class OnShareViaLinkListener
+            implements CompoundButton.OnCheckedChangeListener {
+
+        /**
+         * Called by R.id.shareViaLinkSectionSwitch to create or delete a public link.
+         *
+         * @param switchView    {@link Switch} toggled by the user, R.id.shareViaLinkSectionSwitch
+         * @param isChecked     New switch state.
+         */
+        @Override
+        public void onCheckedChanged(CompoundButton switchView, boolean isChecked) {
+            if (!isResumed()) {
+                // very important, setCheched(...) is called automatically during
+                // Fragment recreation on device rotations
+                return;
+            }
+            if (isChecked) {
+                if (mCapabilities != null &&
+                        mCapabilities.getFilesSharingPublicPasswordEnforced().isTrue()) {
+                    // password enforced by server, request to the user before trying to create
+                    ((FileActivity) getActivity()).getFileOperationsHelper().
+                            requestPasswordForShareViaLink(mFile, true);
 
                 } else {
-                    // TODO real implementation: unshare
-                    // collapse section
-                    getExpirationDateSection().setVisibility(View.GONE);
-                    getPasswordSection().setVisibility(View.GONE);
-                    getGetLinkButton().setVisibility(View.GONE);
+                    // create without password if not enforced by server or we don't know if enforced;
+                    ((FileActivity) getActivity()).getFileOperationsHelper().
+                            shareFileViaLink(mFile, null);
+
+                    // FileActivtiy#onCreateShareViaLinkOperationFinish still handles the guess of enforcement
+                    // for server in versions previous to OwnCloudVersion#MINIMUM_VERSION_CAPABILITIES_API
                 }
+
+            } else {
+                ((FileActivity) getActivity()).getFileOperationsHelper().
+                        unshareFileViaLink(mFile);
             }
-        });
 
-        // Switch for expiration date
-        Switch shareViaLinkExpirationSwitch = (Switch) view.findViewById(R.id.shareViaLinkExpirationSwitch);
-        shareViaLinkExpirationSwitch.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
-            @Override
-            public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
-                if (isChecked) {
-                    // TODO real implementation: update share with expiration date
-                    // show value of expiration date
-                    getExpirationDateValue().setText(R.string.placeholder_timestamp);
+            // undo the toggle to grant the view will be correct if any intermediate dialog is cancelled or
+            // the create/delete operation fails
+            switchView.setOnCheckedChangeListener(null);
+            switchView.toggle();
+            switchView.setOnCheckedChangeListener(mOnShareViaLinkSwitchCheckedChangeListener);
+        }
+    }
 
-                } else {
-                    // TODO real implementation: update share without expiration date
-                    // empty value
-                    getExpirationDateValue().setText(R.string.empty);
-                }
+
+    /**
+     * Binds listener for user actions that start any update on a expiration date
+     * for the public link to the views receiving the user events.
+     *
+     * @param shareView     Root view in the fragment.
+     */
+    private void initExpirationListener(View shareView) {
+        mOnExpirationDateInteractionListener = new OnExpirationDateInteractionListener();
+
+        ((Switch) shareView.findViewById(R.id.shareViaLinkExpirationSwitch)).
+                setOnCheckedChangeListener(mOnExpirationDateInteractionListener);
+
+        shareView.findViewById(R.id.shareViaLinkExpirationLabel).
+                setOnClickListener(mOnExpirationDateInteractionListener);
+
+        shareView.findViewById(R.id.shareViaLinkExpirationValue).
+                setOnClickListener(mOnExpirationDateInteractionListener);
+    }
+
+    /**
+     * Listener for user actions that start any update on the expiration date for the public link.
+     */
+    private class OnExpirationDateInteractionListener
+            implements CompoundButton.OnCheckedChangeListener, View.OnClickListener {
+
+        /**
+         * Called by R.id.shareViaLinkExpirationSwitch to set or clear the expiration date.
+         *
+         * @param switchView    {@link Switch} toggled by the user, R.id.shareViaLinkExpirationSwitch
+         * @param isChecked     New switch state.
+         */
+        @Override
+        public void onCheckedChanged(CompoundButton switchView, boolean isChecked) {
+            if (!isResumed()) {
+                // very important, setCheched(...) is called automatically during
+                // Fragment recreation on device rotations
+                return;
+            }
+            if (isChecked) {
+                ExpirationDatePickerDialogFragment dialog =
+                        ExpirationDatePickerDialogFragment.newInstance(mFile, -1);
+                dialog.show(
+                        getActivity().getSupportFragmentManager(),
+                        ExpirationDatePickerDialogFragment.DATE_PICKER_DIALOG
+                );
+
+            } else {
+                ((FileActivity) getActivity()).getFileOperationsHelper().
+                        setExpirationDateToShareViaLink(mFile, -1);
             }
-        });
 
-        // Switch for password
-        Switch shareViaLinkPasswordSwitch = (Switch) view.findViewById(R.id.shareViaLinkPasswordSwitch);
-        shareViaLinkPasswordSwitch.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
-            @Override
-            public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
-                if (isChecked) {
-                    // TODO real implementation: update share with password
-                    // show
-                    getExpirationPasswordValue().setVisibility(View.VISIBLE);
+            // undo the toggle to grant the view will be correct if the dialog is cancelled
+            switchView.setOnCheckedChangeListener(null);
+            switchView.toggle();
+            switchView.setOnCheckedChangeListener(mOnExpirationDateInteractionListener);
+        }
 
-                } else {
-                    // TODO real implementation: update share without password
-                    // empty value
-                    getExpirationPasswordValue().setVisibility(View.INVISIBLE);
+        /**
+         * Called by R.id.shareViaLinkExpirationLabel or R.id.shareViaLinkExpirationValue
+         * to change the current expiration date.
+         *
+         * @param expirationView      Label or value view touched by the user.
+         */
+        @Override
+        public void onClick(View expirationView) {
+            if (mPublicShare != null && mPublicShare.getExpirationDate() > 0) {
+                long chosenDateInMillis = -1;
+                if (mPublicShare != null) {
+                    chosenDateInMillis = mPublicShare.getExpirationDate();
                 }
+                ExpirationDatePickerDialogFragment dialog =
+                        ExpirationDatePickerDialogFragment.newInstance(
+                                mFile,
+                                chosenDateInMillis
+                        );
+                dialog.show(
+                        getActivity().getSupportFragmentManager(),
+                        ExpirationDatePickerDialogFragment.DATE_PICKER_DIALOG
+                );
             }
-        });
+        }
+    }
 
 
-        return view;
+    /**
+     * Binds listener for user actions that start any update on a password for the public link
+     * to the views receiving the user events.
+     *
+     * @param shareView     Root view in the fragment.
+     */
+    private void initPasswordListener(View shareView) {
+        mOnPasswordInteractionListener = new OnPasswordInteractionListener();
+
+        ((Switch) shareView.findViewById(R.id.shareViaLinkPasswordSwitch)).
+                setOnCheckedChangeListener(mOnPasswordInteractionListener);
+
+        shareView.findViewById(R.id.shareViaLinkPasswordLabel).
+                setOnClickListener(mOnPasswordInteractionListener);
+
+        shareView.findViewById(R.id.shareViaLinkPasswordValue).
+                setOnClickListener(mOnPasswordInteractionListener);
     }
 
+
+    /**
+     * Listener for user actions that start any update on a password for the public link.
+     */
+    private class OnPasswordInteractionListener
+            implements CompoundButton.OnCheckedChangeListener, View.OnClickListener {
+
+        /**
+         * Called by R.id.shareViaLinkPasswordSwitch to set or clear the password.
+         *
+         * @param switchView    {@link Switch} toggled by the user, R.id.shareViaLinkPasswordSwitch
+         * @param isChecked     New switch state.
+         */
+        @Override
+        public void onCheckedChanged(CompoundButton switchView, boolean isChecked) {
+            if (!isResumed()) {
+                // very important, setCheched(...) is called automatically during
+                // Fragment recreation on device rotations
+                return;
+            }
+            if (isChecked) {
+                ((FileActivity) getActivity()).getFileOperationsHelper().
+                        requestPasswordForShareViaLink(mFile, false);
+            } else {
+                ((FileActivity) getActivity()).getFileOperationsHelper().
+                        setPasswordToShareViaLink(mFile, "");   // "" clears
+            }
+
+            // undo the toggle to grant the view will be correct if the dialog is cancelled
+            switchView.setOnCheckedChangeListener(null);
+            switchView.toggle();
+            switchView.setOnCheckedChangeListener(mOnPasswordInteractionListener);
+        }
+
+        /**
+         * Called by R.id.shareViaLinkPasswordLabel or R.id.shareViaLinkPasswordValue
+         * to change the current password.
+         *
+         * @param passwordView      Label or value view touched by the user.
+         */
+        @Override
+        public void onClick(View passwordView) {
+            if (mPublicShare != null && mPublicShare.isPasswordProtected()) {
+                ((FileActivity) getActivity()).getFileOperationsHelper().
+                        requestPasswordForShareViaLink(mFile, false);
+            }
+        }
+    }
+
+
     @Override
     public void onActivityCreated(Bundle savedInstanceState) {
         super.onActivityCreated(savedInstanceState);
+        Log_OC.d(TAG, "onActivityCreated");
+
+        // Load known capabilities of the server from DB
+        refreshCapabilitiesFromDB();
 
         // Load data into the list of private shares
         refreshUsersOrGroupsListFromDB();
@@ -264,8 +470,23 @@ public class ShareFileFragment extends Fragment
         mListener = null;
     }
 
+
+    /**
+     * Get known server capabilities from DB
+     *
+     * Depends on the parent Activity provides a {@link com.owncloud.android.datamodel.FileDataStorageManager}
+     * instance ready to use. If not ready, does nothing.
+     */
+    public void refreshCapabilitiesFromDB() {
+        if (((FileActivity)mListener).getStorageManager() != null) {
+            mCapabilities = ((FileActivity)mListener).getStorageManager().
+                    getCapability(mAccount.name);
+        }
+    }
+
+
     /**
-     * Get users and groups from the DB to fill in the "share with" list
+     * Get users and groups from the DB to fill in the "share with" list.
      *
      * Depends on the parent Activity provides a {@link com.owncloud.android.datamodel.FileDataStorageManager}
      * instance ready to use. If not ready, does nothing.
@@ -301,11 +522,15 @@ public class ShareFileFragment extends Fragment
             noShares.setVisibility(View.GONE);
             usersList.setVisibility(View.VISIBLE);
             usersList.setAdapter(mUserGroupsAdapter);
-
+            setListViewHeightBasedOnChildren(usersList);
         } else {
             noShares.setVisibility(View.VISIBLE);
             usersList.setVisibility(View.GONE);
         }
+
+        // Set Scroll to initial position
+        ScrollView scrollView = (ScrollView) getView().findViewById(R.id.shareScroll);
+        scrollView.scrollTo(0, 0);
     }
 
     @Override
@@ -318,13 +543,18 @@ public class ShareFileFragment extends Fragment
 
 
     /**
-     * Get public link from the DB to fill in the "Share link" section
+     * Get public link from the DB to fill in the "Share link" section in the UI.
+     *
+     * Takes into account server capabilities before reading database.
      *
      * Depends on the parent Activity provides a {@link com.owncloud.android.datamodel.FileDataStorageManager}
      * instance ready to use. If not ready, does nothing.
      */
     public void refreshPublicShareFromDB() {
-        if (((FileActivity) mListener).getStorageManager() != null) {
+        if (isPublicShareDisabled()) {
+            hidePublicShare();
+
+        } else if (((FileActivity) mListener).getStorageManager() != null) {
             // Get public share
             mPublicShare = ((FileActivity) mListener).getStorageManager().getFirstShareByPathAndType(
                     mFile.getRemotePath(),
@@ -332,32 +562,116 @@ public class ShareFileFragment extends Fragment
                     ""
             );
 
-            // Update list of users/groups
+            // Update public share section
             updatePublicShareSection();
         }
     }
 
     /**
+     * @return  'True' when public share is disabled in the server
+     */
+    private boolean isPublicShareDisabled() {
+        return (mCapabilities != null &&
+                mCapabilities.getFilesSharingPublicEnabled().isFalse()
+        );
+    }
+
+    /**
      * Updates in the UI the section about public share with the information in the current
      * public share bound to mFile, if any
      */
     private void updatePublicShareSection() {
         if (mPublicShare != null && ShareType.PUBLIC_LINK.equals(mPublicShare.getShareType())) {
-            // public share bound -> expand section
-            getShareViaLinkSwitch().setChecked(true);
+            /// public share bound -> expand section
+            Switch shareViaLinkSwitch = getShareViaLinkSwitch();
+            if (!shareViaLinkSwitch.isChecked()) {
+                // set null listener before setChecked() to prevent infinite loop of calls
+                shareViaLinkSwitch.setOnCheckedChangeListener(null);
+                shareViaLinkSwitch.setChecked(true);
+                shareViaLinkSwitch.setOnCheckedChangeListener(
+                        mOnShareViaLinkSwitchCheckedChangeListener
+                );
+            }
             getExpirationDateSection().setVisibility(View.VISIBLE);
             getPasswordSection().setVisibility(View.VISIBLE);
-            getGetLinkButton().setVisibility(View.VISIBLE);
+            // GetLink button
+            AppCompatButton getLinkButton = getGetLinkButton();
+            getLinkButton.setVisibility(View.VISIBLE);
+            getLinkButton.setOnClickListener(new View.OnClickListener() {
+                @Override
+                public void onClick(View v) {
+                    //GetLink from the server and show ShareLinkToDialog
+                    ((FileActivity) getActivity()).getFileOperationsHelper().
+                            getFileWithLink(mFile);
+
+                }
+            });
+
+            /// update state of expiration date switch and message depending on expiration date
+            Switch expirationDateSwitch = getExpirationDateSwitch();
+            // set null listener before setChecked() to prevent infinite loop of calls
+            expirationDateSwitch.setOnCheckedChangeListener(null);
+            long expirationDate = mPublicShare.getExpirationDate();
+            if (expirationDate > 0) {
+                if (!expirationDateSwitch.isChecked()) {
+                    expirationDateSwitch.toggle();
+                }
+                String formattedDate =
+                        SimpleDateFormat.getDateInstance().format(
+                                new Date(expirationDate)
+                        );
+                getExpirationDateValue().setText(formattedDate);
+            } else {
+                if (expirationDateSwitch.isChecked()) {
+                    expirationDateSwitch.toggle();
+                }
+                getExpirationDateValue().setText(R.string.empty);
+            }
+            // recover listener
+            expirationDateSwitch.setOnCheckedChangeListener(
+                    mOnExpirationDateInteractionListener
+            );
+
+            /// update state of password switch and message depending on password protection
+            Switch passwordSwitch = getPasswordSwitch();
+            // set null listener before setChecked() to prevent infinite loop of calls
+            passwordSwitch.setOnCheckedChangeListener(null);
+            if (mPublicShare.isPasswordProtected()) {
+                if (!passwordSwitch.isChecked()) {
+                    passwordSwitch.toggle();
+                }
+                getPasswordValue().setVisibility(View.VISIBLE);
+            } else {
+                if (passwordSwitch.isChecked()) {
+                    passwordSwitch.toggle();
+                }
+                getPasswordValue().setVisibility(View.INVISIBLE);
+            }
+            // recover listener
+            passwordSwitch.setOnCheckedChangeListener(
+                    mOnPasswordInteractionListener
+            );
+
 
         } else {
-            // no public share -> collapse section
-            getShareViaLinkSwitch().setChecked(false);
+            /// no public share -> collapse section
+            Switch shareViaLinkSwitch = getShareViaLinkSwitch();
+            if (shareViaLinkSwitch.isChecked()) {
+                shareViaLinkSwitch.setOnCheckedChangeListener(null);
+                getShareViaLinkSwitch().setChecked(false);
+                shareViaLinkSwitch.setOnCheckedChangeListener(
+                        mOnShareViaLinkSwitchCheckedChangeListener
+                );
+            }
             getExpirationDateSection().setVisibility(View.GONE);
             getPasswordSection().setVisibility(View.GONE);
             getGetLinkButton().setVisibility(View.GONE);
         }
     }
 
+
+    /// BEWARE: next methods will failed with NullPointerException if called before onCreateView() finishes
+
     private Switch getShareViaLinkSwitch() {
         return (Switch) getView().findViewById(R.id.shareViaLinkSectionSwitch);
     }
@@ -366,6 +680,10 @@ public class ShareFileFragment extends Fragment
         return getView().findViewById(R.id.shareViaLinkExpirationSection);
     }
 
+    private Switch getExpirationDateSwitch() {
+        return (Switch) getView().findViewById(R.id.shareViaLinkExpirationSwitch);
+    }
+
     private TextView getExpirationDateValue() {
         return (TextView) getView().findViewById(R.id.shareViaLinkExpirationValue);
     }
@@ -374,14 +692,49 @@ public class ShareFileFragment extends Fragment
         return getView().findViewById(R.id.shareViaLinkPasswordSection);
     }
 
-    private TextView getExpirationPasswordValue() {
+    private Switch getPasswordSwitch() {
+        return (Switch) getView().findViewById(R.id.shareViaLinkPasswordSwitch);
+    }
+
+    private TextView getPasswordValue() {
         return (TextView) getView().findViewById(R.id.shareViaLinkPasswordValue);
     }
 
     private AppCompatButton getGetLinkButton() {
-        return (AppCompatButton) getView().findViewById(R.id.shareViewLinkGetLinkButton);
+        return (AppCompatButton) getView().findViewById(R.id.shareViaLinkGetLinkButton);
     }
 
+    /**
+     * Hides all the UI elements related to public share
+     */
+    private void hidePublicShare() {
+        getShareViaLinkSwitch().setVisibility(View.GONE);
+        getExpirationDateSection().setVisibility(View.GONE);
+        getPasswordSection().setVisibility(View.GONE);
+        getGetLinkButton().setVisibility(View.GONE);
+    }
+
+    public static void setListViewHeightBasedOnChildren(ListView listView) {
+        ListAdapter listAdapter = listView.getAdapter();
+        if (listAdapter == null) {
+            return;
+        }
+        int desiredWidth = View.MeasureSpec.makeMeasureSpec(listView.getWidth(), View.MeasureSpec.AT_MOST);
+        int totalHeight = 0;
+        View view = null;
+        for (int i = 0; i < listAdapter.getCount(); i++) {
+            view = listAdapter.getView(i, view, listView);
+            if (i == 0) {
+                view.setLayoutParams(new ViewGroup.LayoutParams(desiredWidth, ViewGroup.LayoutParams.WRAP_CONTENT));
+            }
+            view.measure(desiredWidth, View.MeasureSpec.UNSPECIFIED);
+            totalHeight += view.getMeasuredHeight();
+        }
+        ViewGroup.LayoutParams params = listView.getLayoutParams();
+        params.height = totalHeight + (listView.getDividerHeight() * (listAdapter.getCount() - 1));
+        listView.setLayoutParams(params);
+        listView.requestLayout();
+    }
 
     /**
      * This interface must be implemented by activities that contain this