| /* |
| ** |
| ** Copyright 2013, 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.android.packageinstaller; |
| |
| import android.app.Activity; |
| import android.content.Context; |
| import android.graphics.Rect; |
| import android.support.v4.view.PagerAdapter; |
| import android.support.v4.view.ViewPager; |
| import android.view.View; |
| import android.view.ViewGroup; |
| import android.widget.TabHost; |
| import android.widget.TabWidget; |
| |
| import java.util.ArrayList; |
| |
| /** |
| * This is a helper class that implements the management of tabs and all |
| * details of connecting a ViewPager with associated TabHost. It relies on a |
| * trick. Normally a tab host has a simple API for supplying a View or |
| * Intent that each tab will show. This is not sufficient for switching |
| * between pages. So instead we make the content part of the tab host |
| * 0dp high (it is not shown) and the TabsAdapter supplies its own dummy |
| * view to show as the tab content. It listens to changes in tabs, and takes |
| * care of switch to the correct paged in the ViewPager whenever the selected |
| * tab changes. |
| */ |
| public class TabsAdapter extends PagerAdapter |
| implements TabHost.OnTabChangeListener, ViewPager.OnPageChangeListener { |
| private final Context mContext; |
| private final TabHost mTabHost; |
| private final ViewPager mViewPager; |
| private final ArrayList<TabInfo> mTabs = new ArrayList<TabInfo>(); |
| private final Rect mTempRect = new Rect(); |
| private TabHost.OnTabChangeListener mOnTabChangeListener; |
| |
| static final class TabInfo { |
| private final String tag; |
| private final View view; |
| |
| TabInfo(String _tag, View _view) { |
| tag = _tag; |
| view = _view; |
| } |
| } |
| |
| static class DummyTabFactory implements TabHost.TabContentFactory { |
| private final Context mContext; |
| |
| public DummyTabFactory(Context context) { |
| mContext = context; |
| } |
| |
| @Override |
| public View createTabContent(String tag) { |
| View v = new View(mContext); |
| v.setMinimumWidth(0); |
| v.setMinimumHeight(0); |
| return v; |
| } |
| } |
| |
| public TabsAdapter(Activity activity, TabHost tabHost, ViewPager pager) { |
| mContext = activity; |
| mTabHost = tabHost; |
| mViewPager = pager; |
| mTabHost.setOnTabChangedListener(this); |
| mViewPager.setAdapter(this); |
| mViewPager.setOnPageChangeListener(this); |
| } |
| |
| public void addTab(TabHost.TabSpec tabSpec, View view) { |
| tabSpec.setContent(new DummyTabFactory(mContext)); |
| String tag = tabSpec.getTag(); |
| |
| TabInfo info = new TabInfo(tag, view); |
| mTabs.add(info); |
| mTabHost.addTab(tabSpec); |
| notifyDataSetChanged(); |
| } |
| |
| @Override |
| public int getCount() { |
| return mTabs.size(); |
| } |
| |
| @Override |
| public Object instantiateItem(ViewGroup container, int position) { |
| View view = mTabs.get(position).view; |
| container.addView(view); |
| return view; |
| } |
| |
| @Override |
| public void destroyItem(ViewGroup container, int position, Object object) { |
| container.removeView((View)object); |
| } |
| |
| @Override |
| public boolean isViewFromObject(View view, Object object) { |
| return view == object; |
| } |
| |
| public void setOnTabChangedListener(TabHost.OnTabChangeListener listener) { |
| mOnTabChangeListener = listener; |
| } |
| |
| @Override |
| public void onTabChanged(String tabId) { |
| int position = mTabHost.getCurrentTab(); |
| mViewPager.setCurrentItem(position); |
| if (mOnTabChangeListener != null) { |
| mOnTabChangeListener.onTabChanged(tabId); |
| } |
| } |
| |
| @Override |
| public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) { |
| } |
| |
| @Override |
| public void onPageSelected(int position) { |
| // Unfortunately when TabHost changes the current tab, it kindly |
| // also takes care of putting focus on it when not in touch mode. |
| // The jerk. |
| // This hack tries to prevent this from pulling focus out of our |
| // ViewPager. |
| TabWidget widget = mTabHost.getTabWidget(); |
| int oldFocusability = widget.getDescendantFocusability(); |
| widget.setDescendantFocusability(ViewGroup.FOCUS_BLOCK_DESCENDANTS); |
| mTabHost.setCurrentTab(position); |
| widget.setDescendantFocusability(oldFocusability); |
| |
| // Scroll the current tab into visibility if needed. |
| View tab = widget.getChildTabViewAt(position); |
| mTempRect.set(tab.getLeft(), tab.getTop(), tab.getRight(), tab.getBottom()); |
| widget.requestRectangleOnScreen(mTempRect, false); |
| |
| // Make sure the scrollbars are visible for a moment after selection |
| final View contentView = mTabs.get(position).view; |
| if (contentView instanceof CaffeinatedScrollView) { |
| ((CaffeinatedScrollView) contentView).awakenScrollBars(); |
| } |
| } |
| |
| @Override |
| public void onPageScrollStateChanged(int state) { |
| } |
| } |