Android 5.1 Contacts源码分析：PeopleActivity

Posted 2022-12-08 ximsfei

1. PeopleActivity主界面UI显示

下图为联系人主界面（PeopleActivity）的类图：

PeopleActivity除了实现了类图中的四个接口，还实现了View.OnCreateContextMenuListener和View.OnClickListener，其中Activity源码中已经实现了OnCreateContextMenuListener：

public class Activity extends ContextThemeWrapper
        implements LayoutInflater.Factory2,
        Window.Callback, KeyEvent.Callback,
        OnCreateContextMenuListener, ComponentCallbacks2,
        Window.OnWindowDismissedCallback 

故子类中并不需要去实现OnCreateContextMenuListener了，只需要重写
public void onCreateContextMenu(ContextMenu menu, View v, ContextMenuInfo menuInfo)
该方法，并调用registerForContextMenu(View view)和unregisterForContextMenu(View view)即可。

跟主界面UI息息相关的类主要有
ActionBarAdapter：Adapter for the action bar at the top of the Contacts activity
ViewPagerTabs：ActionBar中添加Tab及其点击事件，联系人、收藏。
以及几个内部类：

private class TabPagerListener implements ViewPager.OnPageChangeListener 
private class TabPagerAdapter extends PagerAdapter 

上图为PeopleActivity UI显示的部分时序图
在createViewsAndFragments中：

private void createViewsAndFragments(Bundle savedState) 
    // Disable the ActionBar so that we can use a Toolbar. This needs to be called before
    // setContentView().
    getWindow().requestFeature(Window.FEATURE_NO_TITLE);

    setContentView(R.layout.people_activity);

    final FragmentManager fragmentManager = getFragmentManager();

    // Hide all tabs (the current tab will later be reshown once a tab is selected)
    final FragmentTransaction transaction = fragmentManager.beginTransaction();

    mTabTitles = new String[TabState.COUNT];
    mTabTitles[TabState.FAVORITES] = getString(R.string.favorites_tab_label);
    mTabTitles[TabState.ALL] = getString(R.string.all_contacts_tab_label);
    mTabPager = getView(R.id.tab_pager);
    mTabPagerAdapter = new TabPagerAdapter();
    mTabPager.setAdapter(mTabPagerAdapter);
    mTabPager.setOnPageChangeListener(mTabPagerListener);

    // Configure toolbar and toolbar tabs. If in landscape mode, we  configure tabs differntly.
    final Toolbar toolbar = getView(R.id.toolbar);
    setActionBar(toolbar);
    final ViewPagerTabs portraitViewPagerTabs
            = (ViewPagerTabs) findViewById(R.id.lists_pager_header);
    ViewPagerTabs landscapeViewPagerTabs = null;
    if (portraitViewPagerTabs ==  null) 
        landscapeViewPagerTabs = (ViewPagerTabs) getLayoutInflater().inflate(
                R.layout.people_activity_tabs_lands, toolbar, /* attachToRoot = */ false);
        mViewPagerTabs = landscapeViewPagerTabs;
     else 
        mViewPagerTabs = portraitViewPagerTabs;
    
    mViewPagerTabs.setViewPager(mTabPager);

    final String FAVORITE_TAG = "tab-pager-favorite";
    final String ALL_TAG = "tab-pager-all";

    // Create the fragments and add as children of the view pager.
    // The pager adapter will only change the visibility; it'll never create/destroy
    // fragments.
    // However, if it's after screen rotation, the fragments have been re-created by
    // the fragment manager, so first see if there're already the target fragments
    // existing.
    mFavoritesFragment = (ContactTileListFragment)
            fragmentManager.findFragmentByTag(FAVORITE_TAG);
    mAllFragment = (DefaultContactBrowseListFragment)
            fragmentManager.findFragmentByTag(ALL_TAG);

    if (mFavoritesFragment == null) 
        mFavoritesFragment = new ContactTileListFragment();
        mAllFragment = new DefaultContactBrowseListFragment();

        transaction.add(R.id.tab_pager, mFavoritesFragment, FAVORITE_TAG);
        transaction.add(R.id.tab_pager, mAllFragment, ALL_TAG);
    

    mFavoritesFragment.setListener(mFavoritesFragmentListener);

    mAllFragment.setOnContactListActionListener(new ContactBrowserActionListener());

    // Hide all fragments for now.  We adjust visibility when we get onSelectedTabChanged()
    // from ActionBarAdapter.
    transaction.hide(mFavoritesFragment);
    transaction.hide(mAllFragment);

    transaction.commitAllowingStateLoss();
    fragmentManager.executePendingTransactions();

    // Setting Properties after fragment is created
    mFavoritesFragment.setDisplayType(DisplayType.STREQUENT);

    mActionBarAdapter = new ActionBarAdapter(this, this, getActionBar(),
            portraitViewPagerTabs, landscapeViewPagerTabs, toolbar);
    mActionBarAdapter.initialize(savedState, mRequest);

    // Add shadow under toolbar
    ViewUtil.addRectangularOutlineProvider(findViewById(R.id.toolbar_parent), getResources());

    // Configure action button
    final View floatingActionButtonContainer = findViewById(
            R.id.floating_action_button_container);
    ViewUtil.setupFloatingActionButton(floatingActionButtonContainer, getResources());
    final ImageButton floatingActionButton = (ImageButton) findViewById(R.id.floating_action_button);
    floatingActionButton.setOnClickListener(this);

    invalidateOptionsMenuIfNeeded();

从Activity.java源码中可以看到：

public void setActionBar(@Nullable Toolbar toolbar) 
    if (getActionBar() instanceof WindowDecorActionBar) 
        throw new IllegalStateException("This Activity already has an action bar supplied " +
                "by the window decor. Do not request Window.FEATURE_ACTION_BAR and set " +
                "android:windowActionBar to false in your theme to use a Toolbar instead.");
    
    ToolbarActionBar tbab = new ToolbarActionBar(toolbar, getTitle(), this);
    mActionBar = tbab;
    mWindow.setCallback(tbab.getWrappedWindowCallback());
    mActionBar.invalidateOptionsMenu();

public void setContentView(View view, ViewGroup.LayoutParams params) 
    getWindow().setContentView(view, params);
    initWindowDecorActionBar();

private void initWindowDecorActionBar() 
    Window window = getWindow();

    // Initializing the window decor can change window feature flags.
    // Make sure that we have the correct set before performing the test below.
    window.getDecorView();

    if (isChild() || !window.hasFeature(Window.FEATURE_ACTION_BAR) || mActionBar != null) 
        return;
    

    mActionBar = new WindowDecorActionBar(this);
    mActionBar.setDefaultDisplayHomeAsUpEnabled(mEnableDefaultActionBarUp);

    mWindow.setDefaultIcon(mActivityInfo.getIconResource());
    mWindow.setDefaultLogo(mActivityInfo.getLogoResource());

我们想要在Activity中使用ToolBar，必须调用getWindow().requestFeature(Window.FEATURE_NO_TITLE);去掉默认的ActionBar，否则会抛出异常，并且在setContentView()中会初始化系统的ActionBar，所以想要去掉默认ActionBar，该方法必须在setContentView()之前调用。

mTabTitles = new String[TabState.COUNT];
mTabTitles[TabState.FAVORITES] = getString(R.string.favorites_tab_label);
mTabTitles[TabState.ALL] = getString(R.string.all_contacts_tab_label);

PeopleActivity的ViewPager中有两个页面，一个是收藏页面（ContactTileListFragment），另一个是所有联系人页面（DefaultContactBrowseListFragment）。
类似的我从Android4.4源码中提取过一个Demo：
在Android中使用ViewPager实现左右滑动页面
PeopleActivity Menu：

public boolean onCreateOptionsMenu(Menu menu) 
    if (!areContactsAvailable()) 
        // If contacts aren't available, hide all menu items.
        return false;
    
    super.onCreateOptionsMenu(menu);

    MenuInflater inflater = getMenuInflater();
    inflater.inflate(R.menu.people_options, menu);

    return true;

在onPrepareOptionsMenu(Menu menu)中会根据是否为搜索模式(isSearchMode)，当前在那个页面中(mActionBarAdapter.getCurrentTab())决定菜单的显示情况。