Android SystemUI之NavigationBar，导航栏（四）
Android SystemUI系列：
1.Android SystemUI之启动流程（一）
2.Android SystemUI之StatusBar，状态栏（二）
3.Android SystemUI之下拉菜单，通知栏，快捷面板（三）
4.Android SystemUI之NavigationBar，导航栏（四）
5.Android SystemUI之Recent，近期列表（五）
一、导航栏的创建
1.先上一幅导航栏的View结构图。如下。
2.导航栏的创建
StatusBar.makeStatusBarView
try {
//创建导航栏
boolean showNav = mWindowManagerService.hasNavigationBar();
if (DEBUG) Log.v(TAG, "hasNavigationBar=" + showNav);
if (showNav) {
createNavigationBar();
}
} catch (RemoteException ex) {
// no window manager? good luck with that
} protected void createNavigationBar() {
mNavigationBarView = NavigationBarFragment.create(mContext, (tag, fragment) -> {
mNavigationBar = (NavigationBarFragment) fragment;
if (mLightBarController != null) {
mNavigationBar.setLightBarController(mLightBarController);
}
mNavigationBar.setCurrentSysuiVisibility(mSystemUiVisibility);
});
}NavigationBarFragment.create
public static View create(Context context, FragmentListener listener) {
WindowManager.LayoutParams lp = new WindowManager.LayoutParams(
LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT,
WindowManager.LayoutParams.TYPE_NAVIGATION_BAR,
WindowManager.LayoutParams.FLAG_TOUCHABLE_WHEN_WAKING
| WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE
| WindowManager.LayoutParams.FLAG_NOT_TOUCH_MODAL
| WindowManager.LayoutParams.FLAG_WATCH_OUTSIDE_TOUCH
| WindowManager.LayoutParams.FLAG_SPLIT_TOUCH
| WindowManager.LayoutParams.FLAG_SLIPPERY,
PixelFormat.TRANSLUCENT);
lp.token = new Binder();
lp.setTitle("NavigationBar");
lp.accessibilityTitle = context.getString(R.string.nav_bar);
lp.windowAnimations = 0;
View navigationBarView = LayoutInflater.from(context).inflate(
R.layout.navigation_bar_window, null);
if (DEBUG) Log.v(TAG, "addNavigationBar: about to add " + navigationBarView);
if (navigationBarView == null) return null;
context.getSystemService(WindowManager.class).addView(navigationBarView, lp);
FragmentHostManager fragmentHost = FragmentHostManager.get(navigationBarView);
NavigationBarFragment fragment = new NavigationBarFragment();
fragmentHost.getFragmentManager().beginTransaction()
.replace(R.id.navigation_bar_frame, fragment, TAG)
.commit();
fragmentHost.addTagListener(TAG, listener);
return navigationBarView;
}上述代码做了两件事：1.创建navigationBarView 并且把navigationBarView添加到windowManager中。
2.创建NavigationBarFragment 替换navigation_bar_window的布局文件，改成navigation_bar
navigation_bar.xml
我们先看NavigationBarInflaterView
public NavigationBarInflaterView(Context context, AttributeSet attrs) {
super(context, attrs);
createInflaters();
mDisplay = ((WindowManager)
context.getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay();
Mode displayMode = mDisplay.getMode();
isRot0Landscape = displayMode.getPhysicalWidth() > displayMode.getPhysicalHeight();
mOverviewProxyService = Dependency.get(OverviewProxyService.class);
}
private void createInflaters() {
mLayoutInflater = LayoutInflater.from(mContext);
Configuration landscape = new Configuration();
landscape.setTo(mContext.getResources().getConfiguration());
landscape.orientation = Configuration.ORIENTATION_LANDSCAPE;
mLandscapeInflater = LayoutInflater.from(mContext.createConfigurationContext(landscape));
}
@Override
protected void onFinishInflate() {
super.onFinishInflate();
inflateChildren();//添加mRot0和mRot90，就是横竖屏的布局
clearViews();//清空所有的view
inflateLayout(getDefaultLayout());
}
private void inflateChildren() {
removeAllViews();
mRot0 = (FrameLayout) mLayoutInflater.inflate(R.layout.navigation_layout, this, false);
mRot0.setId(R.id.rot0);
addView(mRot0);
mRot90 = (FrameLayout) mLayoutInflater.inflate(R.layout.navigation_layout_rot90, this,
false);
mRot90.setId(R.id.rot90);
addView(mRot90);
updateAlternativeOrder();
}上述代码就是在加载导航栏布局文件，如果是0度的时候加载navigation_layout，如果是90度的时候加载navigation_layout_rot90，横屏竖屏加载的layout不同。
protected void inflateLayout(String newLayout) {
mCurrentLayout = newLayout;
if (newLayout == null) {
newLayout = getDefaultLayout();
}
String[] sets = newLayout.split(GRAVITY_SEPARATOR, 3);
if (sets.length != 3) {
Log.d(TAG, "Invalid layout.");
newLayout = getDefaultLayout();
sets = newLayout.split(GRAVITY_SEPARATOR, 3);
}
String[] start = sets[0].split(BUTTON_SEPARATOR);
String[] center = sets[1].split(BUTTON_SEPARATOR);
String[] end = sets[2].split(BUTTON_SEPARATOR);
// Inflate these in start to end order or accessibility traversal will be messed up.
inflateButtons(start, mRot0.findViewById(R.id.ends_group), isRot0Landscape, true);
inflateButtons(start, mRot90.findViewById(R.id.ends_group), !isRot0Landscape, true);
inflateButtons(center, mRot0.findViewById(R.id.center_group), isRot0Landscape, false);
inflateButtons(center, mRot90.findViewById(R.id.center_group), !isRot0Landscape, false);
addGravitySpacer(mRot0.findViewById(R.id.ends_group));
addGravitySpacer(mRot90.findViewById(R.id.ends_group));
inflateButtons(end, mRot0.findViewById(R.id.ends_group), isRot0Landscape, false);
inflateButtons(end, mRot90.findViewById(R.id.ends_group), !isRot0Landscape, false);
updateButtonDispatchersCurrentView();
}
protected String getDefaultLayout() {
final int defaultResource = mOverviewProxyService.shouldShowSwipeUpUI()
? R.string.config_navBarLayoutQuickstep
: R.string.config_navBarLayout;
return mContext.getString(defaultResource);
} protected View inflateButton(String buttonSpec, ViewGroup parent, boolean landscape,
boolean start) {
LayoutInflater inflater = landscape ? mLandscapeInflater : mLayoutInflater;
View v = createView(buttonSpec, parent, inflater);
if (v == null) return null;
v = applySize(v, buttonSpec, landscape, start);//计算view的宽的大小
parent.addView(v);
addToDispatchers(v);
View lastView = landscape ? mLastLandscape : mLastPortrait;
View accessibilityView = v;
if (v instanceof ReverseRelativeLayout) {
accessibilityView = ((ReverseRelativeLayout) v).getChildAt(0);
}
if (lastView != null) {
accessibilityView.setAccessibilityTraversalAfter(lastView.getId());
}
if (landscape) {
mLastLandscape = accessibilityView;
} else {
mLastPortrait = accessibilityView;
}
return v;
} private View createView(String buttonSpec, ViewGroup parent, LayoutInflater inflater) {
View v = null;
String button = extractButton(buttonSpec);
if (LEFT.equals(button)) {
String s = Dependency.get(TunerService.class).getValue(NAV_BAR_LEFT, NAVSPACE);
button = extractButton(s);
} else if (RIGHT.equals(button)) {
String s = Dependency.get(TunerService.class).getValue(NAV_BAR_RIGHT, MENU_IME_ROTATE);
button = extractButton(s);
}
// Let plugins go first so they can override a standard view if they want.
for (NavBarButtonProvider provider : mPlugins) {
v = provider.createView(buttonSpec, parent);
if (v != null) return v;
}
if (HOME.equals(button)) {
v = inflater.inflate(R.layout.home, parent, false);
} else if (BACK.equals(button)) {
v = inflater.inflate(R.layout.back, parent, false);
}
//laiyw add for volume Up/Down
else if (VOLUME_DOWN.equals(button)) {
v = inflater.inflate(R.layout.volume_down, parent, false);
}
else if (VOLUME_UP.equals(button)) {
v = inflater.inflate(R.layout.volume_up, parent, false);
//laiyw add for volume Up/Down
} else if (RECENT.equals(button)) {
v = inflater.inflate(R.layout.recent_apps, parent, false);
} else if (MENU_IME_ROTATE.equals(button)) {
v = inflater.inflate(R.layout.menu_ime, parent, false);
} else if (NAVSPACE.equals(button)) {
v = inflater.inflate(R.layout.nav_key_space, parent, false);
} else if (CLIPBOARD.equals(button)) {
v = inflater.inflate(R.layout.clipboard, parent, false);
} else if (CONTEXTUAL.equals(button)) {
v = inflater.inflate(R.layout.contextual, parent, false);
} else if (button.startsWith(KEY)) {
String uri = extractImage(button);
int code = extractKeycode(button);
v = inflater.inflate(R.layout.custom_key, parent, false);
((KeyButtonView) v).setCode(code);
if (uri != null) {
if (uri.contains(":")) {
((KeyButtonView) v).loadAsync(Icon.createWithContentUri(uri));
} else if (uri.contains("/")) {
int index = uri.indexOf('/');
String pkg = uri.substring(0, index);
int id = Integer.parseInt(uri.substring(index + 1));
((KeyButtonView) v).loadAsync(Icon.createWithResource(pkg, id));
}
}
}
return v;
}上述的代码都比较简单，有两点：
第一、导航栏显示哪些控件是由getDefaultLayout来决定。
一般情况下我们是home，recent，back这三个键，如果你需要加其他的就在这个配置文件夹。同时在createView添加对应的布局文件。
第二、createView方法创建对应的布局文件，并且添加到导航栏中。
home.xml
back.xml
recent_app.xml
那么我们现在布局文件都添加完成了，但是你会发现在NavigationBarInflaterView没有对资源文件添加的代码已经控件点击触摸事件处理逻辑。那么这两部分代码在哪里呢？
答案是：
1.NavigationBarView 完成资源文件添加。
2.NavigationBarFragment 添加点击事件和触摸事件的处理逻辑。
3.NavigationBarView
public NavigationBarView(Context context, AttributeSet attrs) {
super(context, attrs);
mDisplay = ((WindowManager) context.getSystemService(
Context.WINDOW_SERVICE)).getDefaultDisplay();
mVertical = false;
mShowMenu = false;
mShowAccessibilityButton = false;
mLongClickableAccessibilityButton = false;
mOverviewProxyService = Dependency.get(OverviewProxyService.class);
mRecentsOnboarding = new RecentsOnboarding(context, mOverviewProxyService);
mConfiguration = new Configuration();
mConfiguration.updateFrom(context.getResources().getConfiguration());
M : New plugin architecture - Navigation bar plugin
try {
mSystemUICustomizationFactory =
OpSystemUICustomizationFactoryBase.getOpFactory(context);
mNavBarPlugin = mSystemUICustomizationFactory.makeNavigationBar(context);
} catch (Exception e) {
if (DEBUG) Log.d(TAG,"mNavBarPlugin init fail");
e.printStackTrace();
}
reloadNavIcons();//初始化加载资源，主要是图片。
mBarTransitions = new NavigationBarTransitions(this);
mButtonDispatchers.put(R.id.back, new ButtonDispatcher(R.id.back));
mButtonDispatchers.put(R.id.home, new ButtonDispatcher(R.id.home));
mButtonDispatchers.put(R.id.recent_apps, new ButtonDispatcher(R.id.recent_apps));
mButtonDispatchers.put(R.id.volume_down, new ButtonDispatcher(R.id.volume_down));
mButtonDispatchers.put(R.id.volume_up, new ButtonDispatcher(R.id.volume_up));
getVolumeDownButton().setLongClickable(false);
getVolumeUpButton().setLongClickable(false);
mButtonDispatchers.put(R.id.menu, new ButtonDispatcher(R.id.menu));
mButtonDispatchers.put(R.id.ime_switcher, new ButtonDispatcher(R.id.ime_switcher));
mButtonDispatchers.put(R.id.accessibility_button,
new ButtonDispatcher(R.id.accessibility_button));
mButtonDispatchers.put(R.id.rotate_suggestion,
new ButtonDispatcher(R.id.rotate_suggestion));
mButtonDispatchers.put(R.id.menu_container,
new ButtonDispatcher(R.id.menu_container));
mDeadZone = new DeadZone(this);
}
private void reloadNavIcons() {
updateIcons(mContext, Configuration.EMPTY, mConfiguration);
} private void updateIcons(Context ctx, Configuration oldConfig, Configuration newConfig) {
int dualToneDarkTheme = Utils.getThemeAttr(ctx, R.attr.darkIconTheme);
int dualToneLightTheme = Utils.getThemeAttr(ctx, R.attr.lightIconTheme);
Context lightContext = new ContextThemeWrapper(ctx, dualToneLightTheme);
Context darkContext = new ContextThemeWrapper(ctx, dualToneDarkTheme);
if (oldConfig.orientation != newConfig.orientation
|| oldConfig.densityDpi != newConfig.densityDpi) {
mDockedIcon = getDrawable(lightContext, darkContext, R.drawable.ic_sysbar_docked);
mHomeDefaultIcon = getHomeDrawable(lightContext, darkContext);
}
if (oldConfig.densityDpi != newConfig.densityDpi
|| oldConfig.getLayoutDirection() != newConfig.getLayoutDirection()) {
Log.d("yangxiucheng", "oldConfig.densityDpi != newConfig.densityDpi");
mBackIcon = getBackDrawable(lightContext, darkContext);
mRecentIcon = getDrawable(lightContext, darkContext, R.drawable.ic_sysbar_recent);
mMenuIcon = getDrawable(lightContext, darkContext, R.drawable.ic_sysbar_menu);
mAccessibilityIcon = getDrawable(lightContext, darkContext,
R.drawable.ic_sysbar_accessibility_button, false /* hasShadow */);
//mImeIcon = getDrawable(lightContext, darkContext, R.drawable.ic_ime_switcher_default,
//false /* hasShadow */);
updateRotateSuggestionButtonStyle(mRotateBtnStyle, false);
if (ALTERNATE_CAR_MODE_UI) {
updateCarModeIcons(ctx);
}
}
mVolumeDown = getDrawable(ctx,R.drawable.ic_sysbar_volume_down,R.drawable.ic_sysbar_volume_down_dark);
mVolumeUp = getDrawable(ctx,R.drawable.ic_sysbar_volume_up,R.drawable.ic_sysbar_volume_up_dark);
}上述代码都比较简单，可以结合源码看一些细节，就不做太多说明
4.NavigationBarFragment
public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
mNavigationBarView = (NavigationBarView) view;
mNavigationBarView.setDisabledFlags(mDisabledFlags1);
mNavigationBarView.setComponents(mRecents, mDivider, mStatusBar.getPanel());
mNavigationBarView.setOnVerticalChangedListener(this::onVerticalChanged);
mNavigationBarView.setOnTouchListener(this::onNavigationTouch);
if (savedInstanceState != null) {
mNavigationBarView.getLightTransitionsController().restoreState(savedInstanceState);
}
prepareNavigationBarView();//添加home ，recent触摸事件回调
checkNavBarModes();
setDisabled2Flags(mDisabledFlags2);
IntentFilter filter = new IntentFilter(Intent.ACTION_SCREEN_OFF);
filter.addAction(Intent.ACTION_SCREEN_ON);
filter.addAction(Intent.ACTION_USER_SWITCHED);
getContext().registerReceiverAsUser(mBroadcastReceiver, UserHandle.ALL, filter, null, null);
notifyNavigationBarScreenOn();
mOverviewProxyService.addCallback(mOverviewProxyListener);
}
private void prepareNavigationBarView() {
mNavigationBarView.reorient();
//近期列表安静控制
ButtonDispatcher recentsButton = mNavigationBarView.getRecentsButton();
recentsButton.setOnClickListener(this::onRecentsClick);
recentsButton.setOnTouchListener(this::onRecentsTouch);
recentsButton.setLongClickable(true);
recentsButton.setOnLongClickListener(this::onLongPressBackRecents);
ButtonDispatcher backButton = mNavigationBarView.getBackButton();
backButton.setLongClickable(true);
ButtonDispatcher homeButton = mNavigationBarView.getHomeButton();
homeButton.setOnTouchListener(this::onHomeTouch);
homeButton.setOnLongClickListener(this::onHomeLongClick);
ButtonDispatcher accessibilityButton = mNavigationBarView.getAccessibilityButton();
accessibilityButton.setOnClickListener(this::onAccessibilityClick);
accessibilityButton.setOnLongClickListener(this::onAccessibilityLongClick);
updateAccessibilityServicesState(mAccessibilityManager);
ButtonDispatcher rotateSuggestionButton = mNavigationBarView.getRotateSuggestionButton();
rotateSuggestionButton.setOnClickListener(this::onRotateSuggestionClick);
rotateSuggestionButton.setOnHoverListener(this::onRotateSuggestionHover);
updateScreenPinningGestures();
}
上述代码中的setOnClickListener，setOnTouchListener，setLongClickable，setOnLongClickListener就是给对应的控件添加控制代码
到现在为止整个导航栏的View的添加，资源图片的加载，以及点击触摸事件的响应逻辑都讲了，其中还有一些细节，结合源码看应该不难，导航栏的讲解也就到此结束。