commit 7bfdb29e53a0c7dacf093af8145434e2fbf5d047
author Jeff Brown <jeffbrown@google.com> Sun Oct 24 14:39:33 2010 -0700
committer Jeff Brown <jeffbrown@google.com> Tue Jan 11 20:56:04 2011 -0800
tree 85d881eaeb5d300bd3e858b7d23f4257c5fe439f
parent e9bef148d2f82bcb42d1a53731bd8c8de71cc083

Filter virtual keys after touches.  (DO NOT MERGE)

Adds a new virtualKeyQuietTimeMillis configuration resource that sets
the duration for which virtual keys will be dropped after recent touches
on screen.  The default value is 0; it is intended to be overridden
per device using a resource overlay.

This change is designed to help in two cases:

1. Swipes from touchscreen into virtual key area.
2. Accidental taps in virtual key area while using on-screen keyboard.

Bug: 3089163
Change-Id: Id6733c83c2e2bc8d9553aa0e5c1fd74b741bec6e

libs/ui/InputReader.cpp

diff --git a/libs/ui/InputReader.cpp b/libs/ui/InputReader.cpp
index 3197ab2..83b382b 100644
--- a/libs/ui/InputReader.cpp
+++ b/libs/ui/InputReader.cpp
@@ -198,7 +198,7 @@
         const sp<InputReaderPolicyInterface>& policy,
         const sp<InputDispatcherInterface>& dispatcher) :
         mEventHub(eventHub), mPolicy(policy), mDispatcher(dispatcher),
-        mGlobalMetaState(0) {
+        mGlobalMetaState(0), mDisableVirtualKeysTimeout(-1) {
     configureExcludedDevices();
     updateGlobalMetaState();
     updateInputConfiguration();
@@ -453,6 +453,24 @@
     } // release state lock
 }
 
+void InputReader::disableVirtualKeysUntil(nsecs_t time) {
+    mDisableVirtualKeysTimeout = time;
+}
+
+bool InputReader::shouldDropVirtualKey(nsecs_t now,
+        InputDevice* device, int32_t keyCode, int32_t scanCode) {
+    if (now < mDisableVirtualKeysTimeout) {
+        LOGI("Dropping virtual key from device %s because virtual keys are "
+                "temporarily disabled for the next %0.3fms.  keyCode=%d, scanCode=%d",
+                device->getName().string(),
+                (mDisableVirtualKeysTimeout - now) * 0.000001,
+                keyCode, scanCode);
+        return true;
+    } else {
+        return false;
+    }
+}
+
 void InputReader::getInputConfiguration(InputConfiguration* outConfiguration) {
     { // acquire state lock
         AutoMutex _l(mStateLock);
@@ -937,6 +955,11 @@
                 keyCode = mLocked.keyDowns.itemAt(keyDownIndex).keyCode;
             } else {
                 // key down
+                if ((policyFlags & POLICY_FLAG_VIRTUAL)
+                        && mContext->shouldDropVirtualKey(when, getDevice(), keyCode, scanCode)) {
+                    return;
+                }
+
                 mLocked.keyDowns.push();
                 KeyDown& keyDown = mLocked.keyDowns.editTop();
                 keyDown.keyCode = keyCode;
@@ -1340,6 +1363,7 @@
     mParameters.useBadTouchFilter = getPolicy()->filterTouchEvents();
     mParameters.useAveragingTouchFilter = getPolicy()->filterTouchEvents();
     mParameters.useJumpyTouchFilter = getPolicy()->filterJumpyTouchEvents();
+    mParameters.virtualKeyQuietTime = getPolicy()->getVirtualKeyQuietTime();
 }
 
 void TouchInputMapper::dumpParameters(String8& dump) {
@@ -2060,6 +2084,7 @@
 
     TouchResult touchResult = consumeOffScreenTouches(when, policyFlags);
     if (touchResult == DISPATCH_TOUCH) {
+        detectGestures(when);
         dispatchTouches(when, policyFlags);
     }
 
@@ -2145,6 +2170,11 @@
                     if (mCurrentTouch.pointerCount == 1) {
                         const VirtualKey* virtualKey = findVirtualKeyHitLocked(x, y);
                         if (virtualKey) {
+                            if (mContext->shouldDropVirtualKey(when, getDevice(),
+                                    virtualKey->keyCode, virtualKey->scanCode)) {
+                                return DROP_STROKE;
+                            }
+
                             mLocked.currentVirtualKey.down = true;
                             mLocked.currentVirtualKey.downTime = when;
                             mLocked.currentVirtualKey.keyCode = virtualKey->keyCode;
@@ -2182,6 +2212,26 @@
     return touchResult;
 }
 
+void TouchInputMapper::detectGestures(nsecs_t when) {
+    // Disable all virtual key touches that happen within a short time interval of the
+    // most recent touch.  The idea is to filter out stray virtual key presses when
+    // interacting with the touch screen.
+    //
+    // Problems we're trying to solve:
+    //
+    // 1. While scrolling a list or dragging the window shade, the user swipes down into a
+    //    virtual key area that is implemented by a separate touch panel and accidentally
+    //    triggers a virtual key.
+    //
+    // 2. While typing in the on screen keyboard, the user taps slightly outside the screen
+    //    area and accidentally triggers a virtual key.  This often happens when virtual keys
+    //    are layed out below the screen near to where the on screen keyboard's space bar
+    //    is displayed.
+    if (mParameters.virtualKeyQuietTime > 0 && mCurrentTouch.pointerCount != 0) {
+        mContext->disableVirtualKeysUntil(when + mParameters.virtualKeyQuietTime);
+    }
+}
+
 void TouchInputMapper::dispatchTouches(nsecs_t when, uint32_t policyFlags) {
     uint32_t currentPointerCount = mCurrentTouch.pointerCount;
     uint32_t lastPointerCount = mLastTouch.pointerCount;