Android9.0输入法框架(1)
Android系统中，输入法可以是可以安装的，也就是说系统可以有多个输入法（(sougou输入法，百度输入法），但是只有一个是激活的，当然用户可以切换输入法。同时，输入法是以service的方式运行的，输入法同一时间只能服务一个程序，只有最顶层的可见的程序才能接收到输入法的输入数据。
输入法系统的整个框架
InputMethodManagerService（IMMS）负责管理系统的所有输入法，包括输入法service(InputMethodService简称IMS)加载及切换。程序获得焦点时，就会通过InputMethodManager向InputMethodManagerService通知自己获得焦点并请求绑定自己到当前输入法上。同时，当程序的某个需要输入法的view比如EditorView获得焦点时就会通过InputMethodManager向InputMethodManagerService请求显示输入法，而这时InputMethodManagerService收到请求后，会将请求的EditText的数据通信接口发送给当前输入法，并请求显输入法。输入法收到请求后，就显示自己的UI dialog,同时保存目标view的数据结构，当用户实现输入后，直接通过view的数据通信接口将字符传递到对应的View。接下来就来分析这些过程。
InputMethodManager创建
每个程序有一个InputMethodManager实例，这个是程序和InputMethodManagerService通信的接口，该实例在ViewRootImpl初始化的时候创建。
public ViewRootImpl(Context context, Display display) {
mContext = context;
GORDON
mWindowSession = WindowManagerGlobal.getWindowSession();
public static IWindowSession getWindowSession() {
synchronized (WindowManagerGlobal.class) {
if (sWindowSession == null) {
try {
GORDON 这个进程的InputMethodManager实例就生成了
InputMethodManager imm = InputMethodManager.getInstance();
IWindowManager windowManager = getWindowManagerService();
sWindowSession = windowManager.openSession(
new IWindowSessionCallback.Stub() {
@Override
public void onAnimatorScaleChanged(float scale) {
ValueAnimator.setDurationScale(scale);
}
},
imm.getClient(), imm.getInputContext());
} catch (RemoteException e) {
throw e.rethrowFromSystemServer();
}
}
return sWindowSession;
}
}
public static InputMethodManager getInstance() {
synchronized (InputMethodManager.class) {
if (sInstance == null) {
try {
sInstance = new InputMethodManager(Looper.getMainLooper());
} catch (ServiceNotFoundException e) {
throw new IllegalStateException(e);
}
}
return sInstance;
}
}
InputMethodManager(Looper looper) throws ServiceNotFoundException {
GORDON InputMethodManager其实就是一个Binder InputMethodManagerService的proxy
this(IInputMethodManager.Stub.asInterface(
ServiceManager.getServiceOrThrow(Context.INPUT_METHOD_SERVICE)), looper);
}
Client程序的Window获得焦点
时序图
系统WindowManagerService更新焦点window
哪个程序获得焦点是由系统决定的，是由WindowManagerService决定的，当系统的window状态发生变化时(比如window新增，删除）就会调用函数updateFocusedWindowLocked来更新焦点window。
WindowManagerService.java
// TODO: Move to DisplayContent
boolean updateFocusedWindowLocked(int mode, boolean updateInputWindows) {
GORDON 计算焦点
WindowState newFocus = mRoot.computeFocusedWindow();
if (mCurrentFocus != newFocus) {
Trace.traceBegin(TRACE_TAG_WINDOW_MANAGER, "wmUpdateFocus");
// This check makes sure that we don't already have the focus
// change message pending.
mH.removeMessages(H.REPORT_FOCUS_CHANGE);
GORDON 焦点发现改变时发送message REPORT_FOCUS_CHANGE
mH.sendEmptyMessage(H.REPORT_FOCUS_CHANGE);
WindowState computeFocusedWindow() {
// While the keyguard is showing, we must focus anything besides the main display.
// Otherwise we risk input not going to the keyguard when the user expects it to.
final boolean forceDefaultDisplay = mService.isKeyguardShowingAndNotOccluded();
for (int i = mChildren.size() - 1; i >= 0; i--) {
final DisplayContent dc = mChildren.get(i);
GORDON
final WindowState win = dc.findFocusedWindow();
if (win != null) {
if (forceDefaultDisplay && !dc.isDefaultDisplay) {
EventLog.writeEvent(0x534e4554, "71786287", win.mOwnerUid, "");
continue;
}
return win;
}
}
return null;
}
WindowState findFocusedWindow() {
mTmpWindow = null;
GORDON
forAllWindows(mFindFocusedWindow, true /* traverseTopToBottom */);
if (mTmpWindow == null) {
if (DEBUG_FOCUS_LIGHT) Slog.v(TAG_WM, "findFocusedWindow: No focusable windows.");
return null;
}
GORDON mTmpWindow为找到的焦点window
return mTmpWindow;
}
@Override
boolean forAllWindows(ToBooleanFunction callback, boolean traverseTopToBottom) {
// Special handling so we can process IME windows with #forAllImeWindows above their IME
// target, or here in order if there isn't an IME target.
if (traverseTopToBottom) {
for (int i = mChildren.size() - 1; i >= 0; --i) {
final DisplayChildWindowContainer child = mChildren.get(i);
if (skipTraverseChild(child)) {
continue;
}
if (child.forAllWindows(callback, traverseTopToBottom)) {
return true;
}
}
} else {
final int count = mChildren.size();
for (int i = 0; i < count; i++) {
final DisplayChildWindowContainer child = mChildren.get(i);
if (skipTraverseChild(child)) {
continue;
}
if (child.forAllWindows(callback, traverseTopToBottom)) {
return true;
}
}
}
return false;
}
系统通知程序端哪个window获得了焦点
final class H extends android.os.Handler {
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case REPORT_FOCUS_CHANGE: {
WindowState lastFocus;
WindowState newFocus;
AccessibilityController accessibilityController = null;
synchronized(mWindowMap) {
// TODO(multidisplay): Accessibility supported only of default desiplay.
if (mAccessibilityController != null && getDefaultDisplayContentLocked()
.getDisplayId() == DEFAULT_DISPLAY) {
accessibilityController = mAccessibilityController;
}
lastFocus = mLastFocus;
newFocus = mCurrentFocus;
// First notify the accessibility manager for the change so it has
// the windows before the newly focused one starts firing eventgs.
if (accessibilityController != null) {
accessibilityController.onWindowFocusChangedNotLocked();
}
//System.out.println("Changing focus from " + lastFocus + " to " + newFocus);
if (newFocus != null) {
if (DEBUG_FOCUS_LIGHT) Slog.i(TAG_WM, "Gaining focus: " + newFocus);
GORDON 通知新的焦点程序获得了焦点
newFocus.reportFocusChangedSerialized(true, mInTouchMode);
notifyFocusChanged();
}
if (lastFocus != null) {
if (DEBUG_FOCUS_LIGHT) Slog.i(TAG_WM, "Losing focus: " + lastFocus);
GORDON 通知旧的焦点程序失去了焦点
lastFocus.reportFocusChangedSerialized(false, mInTouchMode);
}
} break;
void reportFocusChangedSerialized(boolean focused, boolean inTouchMode) {
try {
GORDON 会调回到ViewRootImpl中的W实例
mClient.windowFocusChanged(focused, inTouchMode);
} catch (RemoteException e) {
}
if (mFocusCallbacks != null) {
final int N = mFocusCallbacks.beginBroadcast();
for (int i=0; iClient程序获得焦点改变事件
public void windowFocusChanged(boolean hasFocus, boolean inTouchMode) {
synchronized (this) {
mWindowFocusChanged = true;
mUpcomingWindowFocus = hasFocus;
mUpcomingInTouchMode = inTouchMode;
}
Message msg = Message.obtain();
msg.what = MSG_WINDOW_FOCUS_CHANGED;
mHandler.sendMessage(msg);
}
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
...
case MSG_WINDOW_FOCUS_CHANGED: {
handleWindowFocusChanged();
} break;
private void handleWindowFocusChanged() {
...
InputMethodManager imm = InputMethodManager.peekInstance();
if (imm != null && mLastWasImTarget && !isInLocalFocusMode()) {
imm.onPreWindowFocus(mView, hasWindowFocus);
}
if (mView != null) {
mAttachInfo.mKeyDispatchState.reset();
GORDON 通知view获得了焦点
mView.dispatchWindowFocusChanged(hasWindowFocus);
mAttachInfo.mTreeObserver.dispatchOnWindowFocusChange(hasWindowFocus);
if (mAttachInfo.mTooltipHost != null) {
mAttachInfo.mTooltipHost.hideTooltip();
}
}
// Note: must be done after the focus change callbacks,
// so all of the view state is set up correctly.
if (hasWindowFocus) {
if (imm != null && mLastWasImTarget && !isInLocalFocusMode()) {
GORDON 通知IMM该window获得了焦点
imm.onPostWindowFocus(mView, mView.findFocus(),
mWindowAttributes.softInputMode,
!mHasHadWindowFocus, mWindowAttributes.flags);
}
View.java
public void dispatchWindowFocusChanged(boolean hasFocus) {
onWindowFocusChanged(hasFocus);
}
public void onWindowFocusChanged(boolean hasWindowFocus) {
InputMethodManager imm = InputMethodManager.peekInstance();
if (!hasWindowFocus) {
if (isPressed()) {
setPressed(false);
}
mPrivateFlags3 &= ~PFLAG3_FINGER_DOWN;
if (imm != null && (mPrivateFlags & PFLAG_FOCUSED) != 0) {
imm.focusOut(this);
}
removeLongPressCallback();
removeTapCallback();
onFocusLost();
} else if (imm != null && (mPrivateFlags & PFLAG_FOCUSED) != 0) {
GORDON 获得焦点的view通过InputMethodManager通知IMMS自己获得了焦点
imm.focusIn(this);
}
refreshDrawableState();
}
焦点View向IMMS请求绑定输入法
InputMethodManager.java
public void focusIn(View view) {
synchronized (mH) {
focusInLocked(view);
}
}
void focusInLocked(View view) {
if (DEBUG) Log.v(TAG, "focusIn: " + dumpViewInfo(view));
if (view != null && view.isTemporarilyDetached()) {
// This is a request from a view that is temporarily detached from a window.
if (DEBUG) Log.v(TAG, "Temporarily detached view, ignoring");
return;
}
if (mCurRootView != view.getRootView()) {
// This is a request from a window that isn't in the window with
// IME focus, so ignore it.
if (DEBUG) Log.v(TAG, "Not IME target window, ignoring");
return;
}
GORDON 保存焦点view
mNextServedView = view;
scheduleCheckFocusLocked(view);
}
static void scheduleCheckFocusLocked(View view) {
ViewRootImpl viewRootImpl = view.getViewRootImpl();
if (viewRootImpl != null) {
viewRootImpl.dispatchCheckFocus();
}
}
检查焦点
public void dispatchCheckFocus() {
if (!mHandler.hasMessages(MSG_CHECK_FOCUS)) {
// This will result in a call to checkFocus() below.
mHandler.sendEmptyMessage(MSG_CHECK_FOCUS);
}
}
final class ViewRootHandler extends Handler {
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case MSG_CHECK_FOCUS: {
InputMethodManager imm = InputMethodManager.peekInstance();
if (imm != null) {
imm.checkFocus();
}
} break;
InputMethodManager.java
public void checkFocus() {
if (checkFocusNoStartInput(false)) {
startInputInner(InputMethodClient.START_INPUT_REASON_CHECK_FOCUS, null, 0, 0, 0);
}
}
boolean startInputInner(@InputMethodClient.StartInputReason final int startInputReason,
IBinder windowGainingFocus, int controlFlags, int softInputMode,
int windowFlags) {
final View view;
synchronized (mH) {
GORDON 之前保存的有焦点的view对象
view = mServedView;
// Make sure we have a window token for the served view.
if (DEBUG) {
Log.v(TAG, "Starting input: view=" + dumpViewInfo(view) +
" reason=" + InputMethodClient.getStartInputReason(startInputReason));
}
if (view == null) {
if (DEBUG) Log.v(TAG, "ABORT input: no served view!");
return false;
}
}
// Now we need to get an input connection from the served view.
// This is complicated in a couple ways: we can't be holding our lock
// when calling out to the view, and we need to make sure we call into
// the view on the same thread that is driving its view hierarchy.
Handler vh = view.getHandler();
if (vh == null) {
// If the view doesn't have a handler, something has changed out
// from under us, so just close the current input.
// If we don't close the current input, the current input method can remain on the
// screen without a connection.
if (DEBUG) Log.v(TAG, "ABORT input: no handler for view! Close current input.");
closeCurrentInput();
return false;
}
if (vh.getLooper() != Looper.myLooper()) {
// The view is running on a different thread than our own, so
// we need to reschedule our work for over there.
if (DEBUG) Log.v(TAG, "Starting input: reschedule to view thread");
vh.post(() -> startInputInner(startInputReason, null, 0, 0, 0));
return false;
}
// Okay we are now ready to call into the served view and have it
// do its stuff.
// Life is good: let's hook everything up!
EditorInfo tba = new EditorInfo();
// Note: Use Context#getOpPackageName() rather than Context#getPackageName() so that the
// system can verify the consistency between the uid of this process and package name passed
// from here. See comment of Context#getOpPackageName() for details.
tba.packageName = view.getContext().getOpPackageName();
tba.fieldId = view.getId();
GORDON 创建数据通信接口，这个接口connection会传递到InputMethodService，后面输入法也会将字符等通过这个接口传回给view
InputConnection ic = view.onCreateInputConnection(tba);
if (DEBUG) Log.v(TAG, "Starting input: tba=" + tba + " ic=" + ic);
synchronized (mH) {
// Now that we are locked again, validate that our state hasn't
// changed.
if (mServedView != view || !mServedConnecting) {
// Something else happened, so abort.
if (DEBUG) Log.v(TAG,
"Starting input: finished by someone else. view=" + dumpViewInfo(view)
+ " mServedView=" + dumpViewInfo(mServedView)
+ " mServedConnecting=" + mServedConnecting);
return false;
}
// If we already have a text box, then this view is already
// connected so we want to restart it.
if (mCurrentTextBoxAttribute == null) {
controlFlags |= CONTROL_START_INITIAL;
}
// Hook 'em up and let 'er rip.
mCurrentTextBoxAttribute = tba;
mServedConnecting = false;
if (mServedInputConnectionWrapper != null) {
mServedInputConnectionWrapper.deactivate();
mServedInputConnectionWrapper = null;
}
ControlledInputConnectionWrapper servedContext;
final int missingMethodFlags;
if (ic != null) {
mCursorSelStart = tba.initialSelStart;
mCursorSelEnd = tba.initialSelEnd;
mCursorCandStart = -1;
mCursorCandEnd = -1;
mCursorRect.setEmpty();
mCursorAnchorInfo = null;
final Handler icHandler;
missingMethodFlags = InputConnectionInspector.getMissingMethodFlags(ic);
if ((missingMethodFlags & InputConnectionInspector.MissingMethodFlags.GET_HANDLER)
!= 0) {
// InputConnection#getHandler() is not implemented.
icHandler = null;
} else {
icHandler = ic.getHandler();
}
GORDON ControlledInputConnectionWrapper是对InputConnection的进一步封装实现跨进程通信
servedContext = new ControlledInputConnectionWrapper(
icHandler != null ? icHandler.getLooper() : vh.getLooper(), ic, this);
} else {
servedContext = null;
missingMethodFlags = 0;
}
mServedInputConnectionWrapper = servedContext;
try {
if (DEBUG) Log.v(TAG, "START INPUT: view=" + dumpViewInfo(view) + " ic="
+ ic + " tba=" + tba + " controlFlags=#"
+ Integer.toHexString(controlFlags));
GORDON 通知IMMS 程序view获得了焦点，请求将view和输入法绑定
final InputBindResult res = mService.startInputOrWindowGainedFocus(
startInputReason, mClient, windowGainingFocus, controlFlags, softInputMode,
windowFlags, tba, servedContext, missingMethodFlags,
view.getContext().getApplicationInfo().targetSdkVersion);
if (DEBUG) Log.v(TAG, "Starting input: Bind result=" + res);
if (res == null) {
Log.wtf(TAG, "startInputOrWindowGainedFocus must not return"
+ " null. startInputReason="
+ InputMethodClient.getStartInputReason(startInputReason)
+ " editorInfo=" + tba
+ " controlFlags=#" + Integer.toHexString(controlFlags));
return false;
}
if (res.id != null) {
setInputChannelLocked(res.channel);
mBindSequence = res.sequence;
mCurMethod = res.method;
mCurId = res.id;
mNextUserActionNotificationSequenceNumber =
res.userActionNotificationSequenceNumber;
} else if (res.channel != null && res.channel != mCurChannel) {
res.channel.dispose();
}
switch (res.result) {
case InputBindResult.ResultCode.ERROR_NOT_IME_TARGET_WINDOW:
mRestartOnNextWindowFocus = true;
break;
}
if (mCurMethod != null && mCompletions != null) {
try {
mCurMethod.displayCompletions(mCompletions);
} catch (RemoteException e) {
}
}
} catch (RemoteException e) {
Log.w(TAG, "IME died: " + mCurId, e);
}
}
return true;
}
IMMS处理view绑定输入法事件
1、启动输入法service
2、绑定输入法window的token
3、请求输入法为焦点程序创建一个连接会话
4、将输入法的接口传递回程序client端
5、绑定输入法和焦点view
1-4是和程序相关的，而5是和view相关的。所以你可以说1~4是用来绑定程序window和输入法，而5是用来绑定程序view和输入法。
输入法还没启动：
弹出输入法会经过1-5
输入法已经启动：
1、但是焦点window发生变化时会经历3-5
2、焦点window没有变化，只是改变了焦点view,则只会经历5
InputMethodManagerService.java
@Override
public InputBindResult startInputOrWindowGainedFocus(
/* @InputMethodClient.StartInputReason */ final int startInputReason,
IInputMethodClient client, IBinder windowToken, int controlFlags, int softInputMode,
int windowFlags, @Nullable EditorInfo attribute, IInputContext inputContext,
/* @InputConnectionInspector.missingMethods */ final int missingMethods,
int unverifiedTargetSdkVersion) {
final InputBindResult result;
if (windowToken != null) {
result = windowGainedFocus(startInputReason, client, windowToken, controlFlags,
softInputMode, windowFlags, attribute, inputContext, missingMethods,
unverifiedTargetSdkVersion);
} else {
GORDON 执行view和输入法的绑定操作 执行步骤1、启动输入法service
result = startInput(startInputReason, client, inputContext, missingMethods, attribute,
controlFlags);
}
if (result == null) {
// This must never happen, but just in case.
Slog.wtf(TAG, "InputBindResult is @NonNull. startInputReason="
+ InputMethodClient.getStartInputReason(startInputReason)
+ " windowFlags=#" + Integer.toHexString(windowFlags)
+ " editorInfo=" + attribute);
return InputBindResult.NULL;
}
return result;
}
启动输入法service InputMethodService
@NonNull
private InputBindResult startInput(
/* @InputMethodClient.StartInputReason */ final int startInputReason,
IInputMethodClient client, IInputContext inputContext,
/* @InputConnectionInspector.missingMethods */ final int missingMethods,
@Nullable EditorInfo attribute, int controlFlags) {
if (!calledFromValidUser()) {
return InputBindResult.INVALID_USER;
}
synchronized (mMethodMap) {
if (DEBUG) {
Slog.v(TAG, "startInput: reason="
+ InputMethodClient.getStartInputReason(startInputReason)
+ " client = " + client.asBinder()
+ " inputContext=" + inputContext
+ " missingMethods="
+ InputConnectionInspector.getMissingMethodFlagsAsString(missingMethods)
+ " attribute=" + attribute
+ " controlFlags=#" + Integer.toHexString(controlFlags));
}
final long ident = Binder.clearCallingIdentity();
try {
return startInputLocked(startInputReason, client, inputContext, missingMethods,
attribute, controlFlags);
} finally {
Binder.restoreCallingIdentity(ident);
}
}
}
@GuardedBy("mMethodMap")
@NonNull
InputBindResult startInputLocked(
/* @InputMethodClient.StartInputReason */ final int startInputReason,
IInputMethodClient client, IInputContext inputContext,
/* @InputConnectionInspector.missingMethods */ final int missingMethods,
@Nullable EditorInfo attribute, int controlFlags) {
// If no method is currently selected, do nothing.
if (mCurMethodId == null) {
return InputBindResult.NO_IME;
}
GORDON client在service端对应的数据结构
ClientState cs = mClients.get(client.asBinder());
if (cs == null) {
throw new IllegalArgumentException("unknown client "
+ client.asBinder());
}
if (attribute == null) {
Slog.w(TAG, "Ignoring startInput with null EditorInfo."
+ " uid=" + cs.uid + " pid=" + cs.pid);
return InputBindResult.NULL_EDITOR_INFO;
}
try {
if (!mIWindowManager.inputMethodClientHasFocus(cs.client)) {
// Check with the window manager to make sure this client actually
// has a window with focus. If not, reject. This is thread safe
// because if the focus changes some time before or after, the
// next client receiving focus that has any interest in input will
// be calling through here after that change happens.
if (DEBUG) {
Slog.w(TAG, "Starting input on non-focused client " + cs.client
+ " (uid=" + cs.uid + " pid=" + cs.pid + ")");
}
return InputBindResult.NOT_IME_TARGET_WINDOW;
}
} catch (RemoteException e) {
}
return startInputUncheckedLocked(cs, inputContext, missingMethods, attribute,
controlFlags, startInputReason);
}
启动输入法前的一系列检查
@GuardedBy("mMethodMap")
@NonNull
InputBindResult startInputUncheckedLocked(@NonNull ClientState cs, IInputContext inputContext,
/* @InputConnectionInspector.missingMethods */ final int missingMethods,
@NonNull EditorInfo attribute, int controlFlags,
/* @InputMethodClient.StartInputReason */ final int startInputReason) {
// If no method is currently selected, do nothing.
if (mCurMethodId == null) {
return InputBindResult.NO_IME;
}
if (!InputMethodUtils.checkIfPackageBelongsToUid(mAppOpsManager, cs.uid,
attribute.packageName)) {
Slog.e(TAG, "Rejecting this client as it reported an invalid package name."
+ " uid=" + cs.uid + " package=" + attribute.packageName);
return InputBindResult.INVALID_PACKAGE_NAME;
}
GORDON 当前活动的程序和新的程序不同
if (mCurClient != cs) {
// Was the keyguard locked when switching over to the new client?
mCurClientInKeyguard = isKeyguardLocked();
// If the client is changing, we need to switch over to the new
// one.
unbindCurrentClientLocked(InputMethodClient.UNBIND_REASON_SWITCH_CLIENT);
if (DEBUG) Slog.v(TAG, "switching to client: client="
+ cs.client.asBinder() + " keyguard=" + mCurClientInKeyguard);
// If the screen is on, inform the new client it is active
if (mIsInteractive) {
executeOrSendMessage(cs.client, mCaller.obtainMessageIO(
MSG_SET_ACTIVE, mIsInteractive ? 1 : 0, cs));
}
}
// Bump up the sequence for this client and attach it.
mCurSeq++;
if (mCurSeq <= 0) mCurSeq = 1;
mCurClient = cs;
mCurInputContext = inputContext;
mCurInputContextMissingMethods = missingMethods;
mCurAttribute = attribute;
// Check if the input method is changing.
if (mCurId != null && mCurId.equals(mCurMethodId)) {
GORDON 连接是否建立，直接绑定
if (cs.curSession != null) {
// Fast case: if we are already connected to the input method,
// then just return it.
return attachNewInputLocked(startInputReason,
(controlFlags&InputMethodManager.CONTROL_START_INITIAL) != 0);
}
if (mHaveConnection) {
if (mCurMethod != null) {
// Return to client, and we will get back with it when
// we have had a session made for it.
GORDON 连接是否创建，如果创建了直接传递给client
requestClientSessionLocked(cs);
return new InputBindResult(
InputBindResult.ResultCode.SUCCESS_WAITING_IME_SESSION,
null, null, mCurId, mCurSeq,
mCurUserActionNotificationSequenceNumber);
} else if (SystemClock.uptimeMillis()
< (mLastBindTime+TIME_TO_RECONNECT)) {
// In this case we have connected to the service, but
// don't yet have its interface. If it hasn't been too
// long since we did the connection, we'll return to
// the client and wait to get the service interface so
// we can report back. If it has been too long, we want
// to fall through so we can try a disconnect/reconnect
// to see if we can get back in touch with the service.
return new InputBindResult(
InputBindResult.ResultCode.SUCCESS_WAITING_IME_BINDING,
null, null, mCurId, mCurSeq,
mCurUserActionNotificationSequenceNumber);
} else {
EventLog.writeEvent(EventLogTags.IMF_FORCE_RECONNECT_IME,
mCurMethodId, SystemClock.uptimeMillis()-mLastBindTime, 0);
}
}
}
GORDON 如果都没有则需要启动输入法并创建连接
return startInputInnerLocked();
}
InputBindResult startInputInnerLocked() {
if (mCurMethodId == null) {
return InputBindResult.NO_IME;
}
if (!mSystemReady) {
// If the system is not yet ready, we shouldn't be running third
// party code.
return new InputBindResult(
InputBindResult.ResultCode.ERROR_SYSTEM_NOT_READY,
null, null, mCurMethodId, mCurSeq,
mCurUserActionNotificationSequenceNumber);
}
InputMethodInfo info = mMethodMap.get(mCurMethodId);
if (info == null) {
throw new IllegalArgumentException("Unknown id: " + mCurMethodId);
}
unbindCurrentMethodLocked(true);
GORDON 1、启动输入法service
mCurIntent = new Intent(InputMethod.SERVICE_INTERFACE);
mCurIntent.setComponent(info.getComponent());
mCurIntent.putExtra(Intent.EXTRA_CLIENT_LABEL,
com.android.internal.R.string.input_method_binding_label);
mCurIntent.putExtra(Intent.EXTRA_CLIENT_INTENT, PendingIntent.getActivity(
mContext, 0, new Intent(Settings.ACTION_INPUT_METHOD_SETTINGS), 0));
GORDON bindService
if (bindCurrentInputMethodServiceLocked(mCurIntent, this, IME_CONNECTION_BIND_FLAGS)) {
mLastBindTime = SystemClock.uptimeMillis();
mHaveConnection = true;
mCurId = info.getId();
GORDON 2、绑定输入法window的token，这个token是给输入法service用来绑定输入法的window的，通过这个token
InputMethodManagerService可以直接管理输入法的window
mCurToken = new Binder();
try {
if (DEBUG) Slog.v(TAG, "Adding window token: " + mCurToken);
mIWindowManager.addWindowToken(mCurToken, TYPE_INPUT_METHOD, DEFAULT_DISPLAY);
} catch (RemoteException e) {
}
return new InputBindResult(
InputBindResult.ResultCode.SUCCESS_WAITING_IME_BINDING,
null, null, mCurId, mCurSeq,
mCurUserActionNotificationSequenceNumber);
}
mCurIntent = null;
Slog.w(TAG, "Failure connecting to input method service: " + mCurIntent);
return InputBindResult.IME_NOT_CONNECTED;
}
@GuardedBy("mMethodMap")
private boolean bindCurrentInputMethodServiceLocked(
Intent service, ServiceConnection conn, int flags) {
if (service == null || conn == null) {
Slog.e(TAG, "--- bind failed: service = " + service + ", conn = " + conn);
return false;
}
if (mBindInstantServiceAllowed) {
flags |= Context.BIND_ALLOW_INSTANT;
}
return mContext.bindServiceAsUser(service, conn, flags,
new UserHandle(mSettings.getCurrentUserId()));
}
输入法启动完成后就在函数onBind 传回一个binder接口
这个onBind在InputMethodService extends AbstractInputMethodService.java
@Override
final public IBinder onBind(Intent intent) {
if (mInputMethod == null) {
mInputMethod = onCreateInputMethodInterface();
}
GORDON IInputMethodWrapper只是一个wrapper，它负责将IMMS的调用转化为message
然后在message线程再调用mInputMethod对应的接口，这样输入法的处理就是异步的了，因此你说它就是mInputMethod
return new IInputMethodWrapper(this, mInputMethod);
}
public abstract AbstractInputMethodImpl onCreateInputMethodInterface();
GORDON InputMethodService.java
@Override
public AbstractInputMethodImpl onCreateInputMethodInterface() {
return new InputMethodImpl();
}
由于IMMS是以bindService的方式启动输入法service，所以当输入法service启动完成后它就会回调IMMS的onServiceConnected
@Override
public void onServiceConnected(ComponentName name, IBinder service) {
synchronized (mMethodMap) {
if (mCurIntent != null && name.equals(mCurIntent.getComponent())) {
GORDON 保存输入法service传递过来的接口
mCurMethod = IInputMethod.Stub.asInterface(service);
if (mCurToken == null) {
Slog.w(TAG, "Service connected without a token!");
unbindCurrentMethodLocked(false);
return;
}
if (DEBUG) Slog.v(TAG, "Initiating attach with token: " + mCurToken);
GORDON 将刚刚创建的window token传递给输入法service,然后输入法用这个token创建window,这样IMMS可以用根据这个token找到输入法在IMMS里
的数据及输入法window在WMS里的数据
executeOrSendMessage(mCurMethod, mCaller.obtainMessageOO(
MSG_ATTACH_TOKEN, mCurMethod, mCurToken));
if (mCurClient != null) {
clearClientSessionLocked(mCurClient);
requestClientSessionLocked(mCurClient);
}
}
}
}
输入法Window token的绑定及使用分析
输入法Window token绑定
IMMS在输入法启动完成并回调onServiceConnected时会将一个Window token传递给输入法。
case MSG_ATTACH_TOKEN:
args = (SomeArgs)msg.obj;
try {
if (DEBUG) Slog.v(TAG, "Sending attach of token: " + args.arg2);
GORDON 调用输入法方法
((IInputMethod)args.arg1).attachToken((IBinder)args.arg2);
} catch (RemoteException e) {
}
args.recycle();
return true;
public class InputMethodService extends AbstractInputMethodService {
public class InputMethodImpl extends AbstractInputMethodImpl {
@Override
public void attachToken(IBinder token) {
if (mToken == null) {
mToken = token;
GORDON 这样输入法的window就绑定这个window token
mWindow.setToken(token);
}
}
输入法Window token使用
系统存在多个输入法，所以输入法要和IMMS通信，必须要个机制来标示自己是哪个输入法，这个就是通过上面的输入法Window token来实现的,比如输入法自己关闭自己
InputMethodService.java
public void requestHideSelf(int flags) {
mImm.hideSoftInputFromInputMethodInternal(mToken, flags);
}
public void hideSoftInputFromInputMethodInternal(IBinder token, int flags) {
try {
mService.hideMySoftInput(token, flags);
} catch (RemoteException e) {
throw e.rethrowFromSystemServer();
}
}
IMMS
@Override
public void hideMySoftInput(IBinder token, int flags) {
if (!calledFromValidUser()) {
return;
}
synchronized (mMethodMap) {
if (!calledWithValidToken(token)) {
return;
}
long ident = Binder.clearCallingIdentity();
try {
hideCurrentInputLocked(flags, null);
} finally {
Binder.restoreCallingIdentity(ident);
}
}
}
输入法连接会话创建
回到IMMS onServiceConnected
@Override
public void onServiceConnected(ComponentName name, IBinder service) {
synchronized (mMethodMap) {
if (mCurIntent != null && name.equals(mCurIntent.getComponent())) {
mCurMethod = IInputMethod.Stub.asInterface(service);
if (mCurToken == null) {
Slog.w(TAG, "Service connected without a token!");
unbindCurrentMethodLocked(false);
return;
}
if (DEBUG) Slog.v(TAG, "Initiating attach with token: " + mCurToken);
executeOrSendMessage(mCurMethod, mCaller.obtainMessageOO(
MSG_ATTACH_TOKEN, mCurMethod, mCurToken));
if (mCurClient != null) {
clearClientSessionLocked(mCurClient);
GORDON
requestClientSessionLocked(mCurClient);
}
}
}
}
GORDON 创建view和输入法连接的session
void requestClientSessionLocked(ClientState cs) {
if (!cs.sessionRequested) {
if (DEBUG) Slog.v(TAG, "Creating new session for client " + cs);
InputChannel[] channels = InputChannel.openInputChannelPair(cs.toString());
cs.sessionRequested = true;
executeOrSendMessage(mCurMethod, mCaller.obtainMessageOOO(
MSG_CREATE_SESSION, mCurMethod, channels[1],
new MethodCallback(this, mCurMethod, channels[0])));
}
}
case MSG_CREATE_SESSION: {
args = (SomeArgs)msg.obj;
IInputMethod method = (IInputMethod)args.arg1;
InputChannel channel = (InputChannel)args.arg2;
try {
GORDON 输入法创建的session
method.createSession(channel, (IInputSessionCallback)args.arg3);
} catch (RemoteException e) {
} finally {
// Dispose the channel if the input method is not local to this process
// because the remote proxy will get its own copy when unparceled.
if (channel != null && Binder.isProxy(method)) {
channel.dispose();
}
}
args.recycle();
return true;
}
IMS -> createSession
public abstract class AbstractInputMethodImpl implements InputMethod {
/**
* Instantiate a new client session for the input method, by calling
* back to {@link AbstractInputMethodService#onCreateInputMethodSessionInterface()
* AbstractInputMethodService.onCreateInputMethodSessionInterface()}.
*/
@MainThread
public void createSession(SessionCallback callback) {
callback.sessionCreated(onCreateInputMethodSessionInterface());
}
最终调用IMMS 的onSessionCreated
void onSessionCreated(IInputMethod method, IInputMethodSession session,
InputChannel channel) {
synchronized (mMethodMap) {
if (mCurMethod != null && method != null
&& mCurMethod.asBinder() == method.asBinder()) {
if (mCurClient != null) {
clearClientSessionLocked(mCurClient);
mCurClient.curSession = new SessionState(mCurClient,
method, session, channel);
InputBindResult res = attachNewInputLocked(
InputMethodClient.START_INPUT_REASON_SESSION_CREATED_BY_IME, true);
if (res.method != null) {
executeOrSendMessage(mCurClient.client, mCaller.obtainMessageOO(
MSG_BIND_CLIENT, mCurClient.client, res));
}
return;
}
}
}
// Session abandoned. Close its associated input channel.
channel.dispose();
}
传递输入法接口给程序
case MSG_BIND_CLIENT: {
args = (SomeArgs)msg.obj;
IInputMethodClient client = (IInputMethodClient)args.arg1;
InputBindResult res = (InputBindResult)args.arg2;
try {
GORDON 回调到client端
client.onBindMethod(res);
} catch (RemoteException e) {
Slog.w(TAG, "Client died receiving input method " + args.arg2);
} finally {
// Dispose the channel if the input method is not local to this process
// because the remote proxy will get its own copy when unparceled.
if (res.channel != null && Binder.isProxy(client)) {
res.channel.dispose();
}
}
args.recycle();
return true;
}
输入法和view绑定
IMMS
创建完session后，回调onSessionCreated输入法和view绑定
void onSessionCreated(IInputMethod method, IInputMethodSession session,
InputChannel channel) {
synchronized (mMethodMap) {
if (mCurMethod != null && method != null
&& mCurMethod.asBinder() == method.asBinder()) {
if (mCurClient != null) {
clearClientSessionLocked(mCurClient);
mCurClient.curSession = new SessionState(mCurClient,
method, session, channel);
GORDON 绑定
InputBindResult res = attachNewInputLocked(
InputMethodClient.START_INPUT_REASON_SESSION_CREATED_BY_IME, true);
if (res.method != null) {
executeOrSendMessage(mCurClient.client, mCaller.obtainMessageOO(
MSG_BIND_CLIENT, mCurClient.client, res));
}
return;
}
}
}
// Session abandoned. Close its associated input channel.
channel.dispose();
}
@GuardedBy("mMethodMap")
@NonNull
InputBindResult attachNewInputLocked(
/* @InputMethodClient.StartInputReason */ final int startInputReason, boolean initial) {
if (!mBoundToMethod) {
GORDON 如果没有绑定则绑定，否则执行下面操作
executeOrSendMessage(mCurMethod, mCaller.obtainMessageOO(
MSG_BIND_INPUT, mCurMethod, mCurClient.binding));
mBoundToMethod = true;
}
final Binder startInputToken = new Binder();
final StartInputInfo info = new StartInputInfo(mCurToken, mCurId, startInputReason,
!initial, mCurFocusedWindow, mCurAttribute, mCurFocusedWindowSoftInputMode,
mCurSeq);
mStartInputMap.put(startInputToken, info);
mStartInputHistory.addEntry(info);
final SessionState session = mCurClient.curSession;
executeOrSendMessage(session.method, mCaller.obtainMessageIIOOOO(
MSG_START_INPUT, mCurInputContextMissingMethods, initial ? 0 : 1 /* restarting */,
startInputToken, session, mCurInputContext, mCurAttribute));
if (mShowRequested) {
if (DEBUG) Slog.v(TAG, "Attach new input asks to show input");
showCurrentInputLocked(getAppShowFlags(), null);
}
return new InputBindResult(InputBindResult.ResultCode.SUCCESS_WITH_IME_SESSION,
session.session, (session.channel != null ? session.channel.dup() : null),
mCurId, mCurSeq, mCurUserActionNotificationSequenceNumber);
}
GORDON 绑定输入法
case MSG_BIND_INPUT:
args = (SomeArgs)msg.obj;
try {
((IInputMethod)args.arg1).bindInput((InputBinding)args.arg2);
} catch (RemoteException e) {
}
args.recycle();
return true;
GORDON 启动输入法
case MSG_START_INPUT: {
final int missingMethods = msg.arg1;
final boolean restarting = msg.arg2 != 0;
args = (SomeArgs) msg.obj;
final IBinder startInputToken = (IBinder) args.arg1;
final SessionState session = (SessionState) args.arg2;
final IInputContext inputContext = (IInputContext) args.arg3;
final EditorInfo editorInfo = (EditorInfo) args.arg4;
try {
setEnabledSessionInMainThread(session);
session.method.startInput(startInputToken, inputContext, missingMethods,
editorInfo, restarting);
} catch (RemoteException e) {
}
args.recycle();
return true;
}
IMS
@Override
public void startInput(InputConnection ic, EditorInfo attribute) {
if (DEBUG) Log.v(TAG, "startInput(): editor=" + attribute);
doStartInput(ic, attribute, false);
}
void doStartInput(InputConnection ic, EditorInfo attribute, boolean restarting) {
if (!restarting) {
doFinishInput();
}
mInputStarted = true;
mStartedInputConnection = ic;
mInputEditorInfo = attribute;
initialize();
if (DEBUG) Log.v(TAG, "CALL: onStartInput");
onStartInput(attribute, restarting);
if (mWindowVisible) {
if (mShowInputRequested) {
if (DEBUG) Log.v(TAG, "CALL: onStartInputView");
mInputViewStarted = true;
GORDON 输入法需要在此实现view的内容
onStartInputView(mInputEditorInfo, restarting);
startExtractingText(true);
} else if (mCandidatesVisibility == View.VISIBLE) {
if (DEBUG) Log.v(TAG, "CALL: onStartCandidatesView");
mCandidatesViewStarted = true;
onStartCandidatesView(mInputEditorInfo, restarting);
}
}
}
绑定完成了但是还没有显示输入法，系统会调用windowGainFocus来显示输入法
程序焦点获取事件导致输入法显示
从上面可以知道程序获得焦点时，程序端会先间接的调用IMMS的startInput将焦点View绑定到输入法，然后会调用IMMS的windowGainFocus函数，这个函数就可能显示输入法, 是否显示输入法由焦点view的属性决定。过程流程图如下
