Add IMM#invalidateInput()

Historically TextView#setText() has internally called

  InputMethodManager#restartInput(View)

simply because the text seen from the IME is going to be out-of-sync.

Although this behavior is semantically helpful for IMEs, especially
after the initial surrounding text information became available in
EditorInfo, issuing a sync IPC from the calling thread (UI thread
actually) is not plausible from the performance perspective.

This CL fills this gap by adding a new API

  InputMethodManager#invalidateInput(View)

for the scenario where apps independently modify the text with keeping
other text metadata such as input-type to be the same.

All the observable behaviors from the IME remain to be the same as

  InputMethodManager#restartInput(View).

For instance, any pending tasks that are already issued with

  InputMethodService#getCurrentInputConnection()

will be effectively cancelled by using a recently added mechanism [1].

 [1]: I383c3958d2ac1a8d217706509fa12a92b381bbb3

Fix: 203086369
Test: atest -c CtsInputMethodTestCases:InputMethodStartInputLifecycleTest
Change-Id: I3161755779080f98bcef0e47dd0c5247d8a3a256

1 files changed, 10 insertions, 0 deletions

diff --git a/core/java/android/inputmethodservice/AbstractInputMethodService.java b/core/java/android/inputmethodservice/AbstractInputMethodService.java
index 4ecd15e002ef..75beacfb12f3 100644
--- a/core/java/android/inputmethodservice/AbstractInputMethodService.java
+++ b/core/java/android/inputmethodservice/AbstractInputMethodService.java
@@ -68,6 +68,16 @@ public abstract class AbstractInputMethodService extends WindowProviderService
     private InputMethod mInputMethod;
 
     /**
+     * @return {@link InputMethod} instance returned from {@link #onCreateInputMethodInterface()}.
+     *         {@code null} if {@link #onCreateInputMethodInterface()} is not yet called.
+     * @hide
+     */
+    @Nullable
+    protected final InputMethod getInputMethodInternal() {
+        return mInputMethod;
+    }
+
+    /**
      * Keep the strong reference to {@link InputMethodServiceInternal} to ensure that it will not be
      * garbage-collected until {@link AbstractInputMethodService} gets garbage-collected.
      *