Java tutorial
/* * Copyright 2012 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 behsaman.storytellerandroid; import java.util.ArrayList; import android.app.Fragment; import android.app.FragmentManager; import android.content.Context; import android.content.Intent; import android.os.Bundle; import android.support.v13.app.FragmentStatePagerAdapter; import android.support.v4.app.FragmentActivity; import android.support.v4.app.NavUtils; import android.support.v4.view.PagerAdapter; import android.support.v4.view.ViewPager; import android.view.Menu; import android.view.MenuItem; import behsaman.storytellerandroid.datamodel.PieceModel; import behsaman.storytellerandroid.datamodel.StoryModel; /** * Demonstrates a "screen-slide" animation using a {@link ViewPager}. Because {@link ViewPager} * automatically plays such an animation when calling {@link ViewPager#setCurrentItem(int)}, there * isn't any animation-specific code in this sample. * * <p>This sample shows a "next" button that advances the user to the next step in a wizard, * animating the current screen out (to the left) and the next screen in (from the right). The * reverse animation is played when the user presses the "previous" button.</p> * * @see ScreenSlidePageFragment */ public class TextviewerSlideActivity extends FragmentActivity { private static final String TAG = "TextviewerSlideActivity"; /** * The pager widget, which handles animation and allows swiping horizontally to access previous * and next wizard steps. */ private ViewPager mPager; //Story Pieces ArrayList<Object> pieces = new ArrayList<Object>(); //Story Model StoryModel storyModel = null; /** * The pager adapter, which provides the pages to the view pager widget. */ private PagerAdapter mPagerAdapter; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_screen_slide); //Get Info from Intent and setup pager setupPager(); } private void setupPager() { Intent intent = getIntent(); this.pieces = (ArrayList<Object>) intent.getSerializableExtra(StoryPageActivity.STORY_PIECES_KEY); this.storyModel = (StoryModel) intent.getSerializableExtra(StoryPageActivity.STORY_MODEL_KEY); Integer selected_page = (Integer) intent.getSerializableExtra(StoryPageActivity.STORY_SELECTED_PIECE_KEY); // Instantiate a ViewPager and a PagerAdapter. mPager = (ViewPager) findViewById(R.id.pager); mPager.setPageTransformer(true, new ZoomOutPageTransformer()); mPagerAdapter = new ScreenSlidePagerAdapter(getFragmentManager(), this.pieces, storyModel, this); mPager.setAdapter(mPagerAdapter); mPager.setOnPageChangeListener(new ViewPager.SimpleOnPageChangeListener() { @Override public void onPageSelected(int position) { // When changing pages, reset the action bar actions since they are dependent // on which page is currently active. An alternative approach is to have each // fragment expose actions itself (rather than the activity exposing actions), // but for simplicity, the activity provides the actions in this sample. invalidateOptionsMenu(); } }); //Set page navigation if (selected_page != null) mPager.setCurrentItem(selected_page); } @Override public boolean onCreateOptionsMenu(Menu menu) { super.onCreateOptionsMenu(menu); getMenuInflater().inflate(R.menu.screen_slide, menu); menu.findItem(R.id.action_previous).setEnabled(mPager.getCurrentItem() > 0); // Add either a "next" or "finish" button to the action bar, depending on which page // is currently selected. MenuItem item = menu.add(Menu.NONE, R.id.action_next, Menu.NONE, (mPager.getCurrentItem() == mPagerAdapter.getCount() - 1) ? "Finish" : "Next"); item.setShowAsAction(MenuItem.SHOW_AS_ACTION_IF_ROOM | MenuItem.SHOW_AS_ACTION_WITH_TEXT); return true; } @Override public boolean onOptionsItemSelected(MenuItem item) { switch (item.getItemId()) { case android.R.id.home: // Navigate "up" the demo structure to the launchpad activity. // See http://developer.android.com/design/patterns/navigation.html for more. NavUtils.navigateUpTo(this, new Intent(this, MainActivity.class)); return true; case R.id.action_previous: // Go to the previous step in the wizard. If there is no previous step, // setCurrentItem will do nothing. mPager.setCurrentItem(mPager.getCurrentItem() - 1); return true; case R.id.action_next: // Advance to the next step in the wizard. If there is no next step, setCurrentItem // will do nothing. mPager.setCurrentItem(mPager.getCurrentItem() + 1); return true; } return super.onOptionsItemSelected(item); } /*@Override public void onBackPressed() { if (mPager.getCurrentItem() == 0) { // If the user is currently looking at the first step, allow the system to handle the // Back button. This calls finish() on this activity and pops the back stack. super.onBackPressed(); } else { // Otherwise, select the previous step. mPager.setCurrentItem(mPager.getCurrentItem() - 1); } }*/ /** * A simple pager adapter that represents 5 {@link ScreenSlidePageFragment} objects, in * sequence. */ private class ScreenSlidePagerAdapter extends FragmentStatePagerAdapter { protected ArrayList<Object> data; protected StoryModel model; protected Context parentContext; public ScreenSlidePagerAdapter(FragmentManager fm, ArrayList<Object> d, StoryModel storyModel, Context c) { super(fm); this.data = d; this.model = storyModel; this.parentContext = c; } @Override public Fragment getItem(int position) { return ScreenSlidePageFragment.create((PieceModel) data.get(position), model.getType(), parentContext); } @Override public int getCount() { return data.size(); } } }