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/*
* Copyright (C) 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 com.example.android.displayingbitmaps.ui;
import android.annotation.TargetApi;
import android.app.ActionBar;
import android.os.Build.VERSION_CODES;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentStatePagerAdapter;
import android.support.v4.app.NavUtils;
import android.support.v4.view.ViewPager;
import android.util.DisplayMetrics;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.WindowManager.LayoutParams;
import android.widget.Toast;
import com.example.android.displayingbitmaps.BuildConfig;
import com.example.android.displayingbitmaps.R;
import com.example.android.displayingbitmaps.provider.Images;
import com.example.android.displayingbitmaps.util.ImageCache;
import com.example.android.displayingbitmaps.util.ImageFetcher;
import com.example.android.displayingbitmaps.util.Utils;
public class ImageDetailActivity extends FragmentActivity implements OnClickListener {
private static final String IMAGE_CACHE_DIR = "images";
public static final String EXTRA_IMAGE = "extra_image";
private ImagePagerAdapter mAdapter;
private ImageFetcher mImageFetcher;
private ViewPager mPager;
@TargetApi(VERSION_CODES.HONEYCOMB)
@Override
public void onCreate(Bundle savedInstanceState) {
if (BuildConfig.DEBUG) {
Utils.enableStrictMode();
}
super.onCreate(savedInstanceState);
setContentView(R.layout.image_detail_pager);
// Fetch screen height and width, to use as our max size when loading images as this
// activity runs full screen
final DisplayMetrics displayMetrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(displayMetrics);
final int height = displayMetrics.heightPixels;
final int width = displayMetrics.widthPixels;
// For this sample we'll use half of the longest width to resize our images. As the
// image scaling ensures the image is larger than this, we should be left with a
// resolution that is appropriate for both portrait and landscape. For best image quality
// we shouldn't divide by 2, but this will use more memory and require a larger memory
// cache.
final int longest = (height > width ? height : width) / 2;
ImageCache.ImageCacheParams cacheParams =
new ImageCache.ImageCacheParams(this, IMAGE_CACHE_DIR);
cacheParams.setMemCacheSizePercent(0.25f); // Set memory cache to 25% of app memory
// The ImageFetcher takes care of loading images into our ImageView children asynchronously
mImageFetcher = new ImageFetcher(this, longest);
mImageFetcher.addImageCache(getSupportFragmentManager(), cacheParams);
mImageFetcher.setImageFadeIn(false);
// Set up ViewPager and backing adapter
mAdapter = new ImagePagerAdapter(getSupportFragmentManager(), Images.imageUrls.length);
mPager = (ViewPager) findViewById(R.id.pager);
mPager.setAdapter(mAdapter);
mPager.setPageMargin((int) getResources().getDimension(R.dimen.horizontal_page_margin));
mPager.setOffscreenPageLimit(2);
// Set up activity to go full screen
getWindow().addFlags(LayoutParams.FLAG_FULLSCREEN);
// Enable some additional newer visibility and ActionBar features to create a more
// immersive photo viewing experience
if (Utils.hasHoneycomb()) {
final ActionBar actionBar = getActionBar();
// Hide title text and set home as up
actionBar.setDisplayShowTitleEnabled(false);
actionBar.setDisplayHomeAsUpEnabled(true);
// Hide and show the ActionBar as the visibility changes
mPager.setOnSystemUiVisibilityChangeListener(
new View.OnSystemUiVisibilityChangeListener() {
@Override
public void onSystemUiVisibilityChange(int vis) {
if ((vis & View.SYSTEM_UI_FLAG_LOW_PROFILE) != 0) {
actionBar.hide();
} else {
actionBar.show();
}
}
});
// Start low profile mode and hide ActionBar
mPager.setSystemUiVisibility(View.SYSTEM_UI_FLAG_LOW_PROFILE);
actionBar.hide();
}
// Set the current item based on the extra passed in to this activity
final int extraCurrentItem = getIntent().getIntExtra(EXTRA_IMAGE, -1);
if (extraCurrentItem != -1) {
mPager.setCurrentItem(extraCurrentItem);
}
}
@Override
public void onResume() {
super.onResume();
mImageFetcher.setExitTasksEarly(false);
}
@Override
protected void onPause() {
super.onPause();
mImageFetcher.setExitTasksEarly(true);
mImageFetcher.flushCache();
}
@Override
protected void onDestroy() {
super.onDestroy();
mImageFetcher.closeCache();
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
NavUtils.navigateUpFromSameTask(this);
return true;
case R.id.clear_cache:
mImageFetcher.clearCache();
Toast.makeText(
this, R.string.clear_cache_complete_toast,Toast.LENGTH_SHORT).show();
return true;
}
return super.onOptionsItemSelected(item);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main_menu, menu);
return true;
}
/**
* Called by the ViewPager child fragments to load images via the one ImageFetcher
*/
public ImageFetcher getImageFetcher() {
return mImageFetcher;
}
/**
* The main adapter that backs the ViewPager. A subclass of FragmentStatePagerAdapter as there
* could be a large number of items in the ViewPager and we don't want to retain them all in
* memory at once but create/destroy them on the fly.
*/
private class ImagePagerAdapter extends FragmentStatePagerAdapter {
private final int mSize;
public ImagePagerAdapter(FragmentManager fm, int size) {
super(fm);
mSize = size;
}
@Override
public int getCount() {
return mSize;
}
@Override
public Fragment getItem(int position) {
return ImageDetailFragment.newInstance(Images.imageUrls[position]);
}
}
/**
* Set on the ImageView in the ViewPager children fragments, to enable/disable low profile mode
* when the ImageView is touched.
*/
@TargetApi(VERSION_CODES.HONEYCOMB)
@Override
public void onClick(View v) {
final int vis = mPager.getSystemUiVisibility();
if ((vis & View.SYSTEM_UI_FLAG_LOW_PROFILE) != 0) {
mPager.setSystemUiVisibility(View.SYSTEM_UI_FLAG_VISIBLE);
} else {
mPager.setSystemUiVisibility(View.SYSTEM_UI_FLAG_LOW_PROFILE);
}
}
}
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