Add panic detection to back button
Adds "panic" detection to the back button. Implemented solution
uses 4x button presses in a short duration to detect for "panic".
The value used to determine the duration between key up and key down
that still count as a multi-button press is configurable via the
Settings Provider.
BUG: 28027764
Change-Id: Ibf1370ff3cb539a9a54002a8704922744a3ca5d7
diff --git a/core/java/android/provider/Settings.java b/core/java/android/provider/Settings.java
index 5da55b1..f4c642f 100755
--- a/core/java/android/provider/Settings.java
+++ b/core/java/android/provider/Settings.java
@@ -5345,6 +5345,13 @@
public static final String LONG_PRESS_TIMEOUT = "long_press_timeout";
/**
+ * The duration in milliseconds between the first tap's up event and the second tap's
+ * down event for an interaction to be considered part of the same multi-press.
+ * @hide
+ */
+ public static final String MULTI_PRESS_TIMEOUT = "multi_press_timeout";
+
+ /**
* List of the enabled print services.
*
* N and beyond uses {@link #DISABLED_PRINT_SERVICES}. But this might be used in an upgrade
diff --git a/core/java/android/view/ViewConfiguration.java b/core/java/android/view/ViewConfiguration.java
index 4d584a3..9a73d0b 100644
--- a/core/java/android/view/ViewConfiguration.java
+++ b/core/java/android/view/ViewConfiguration.java
@@ -64,6 +64,12 @@
private static final int DEFAULT_LONG_PRESS_TIMEOUT = 500;
/**
+ * Defines the default duration in milliseconds between the first tap's up event and the second
+ * tap's down event for an interaction to be considered part of the same multi-press.
+ */
+ private static final int DEFAULT_MULTI_PRESS_TIMEOUT = 300;
+
+ /**
* Defines the time between successive key repeats in milliseconds.
*/
private static final int KEY_REPEAT_DELAY = 50;
@@ -441,6 +447,16 @@
}
/**
+ * @return the duration in milliseconds between the first tap's up event and the second tap's
+ * down event for an interaction to be considered part of the same multi-press.
+ * @hide
+ */
+ public static int getMultiPressTimeout() {
+ return AppGlobals.getIntCoreSetting(Settings.Secure.MULTI_PRESS_TIMEOUT,
+ DEFAULT_MULTI_PRESS_TIMEOUT);
+ }
+
+ /**
* @return the time before the first key repeat in milliseconds.
*/
public static int getKeyRepeatTimeout() {
diff --git a/core/res/res/values/config.xml b/core/res/res/values/config.xml
index 018072b..18a6a83 100644
--- a/core/res/res/values/config.xml
+++ b/core/res/res/values/config.xml
@@ -796,6 +796,12 @@
-->
<integer name="config_longPressOnBackBehavior">0</integer>
+ <!-- Control the behavior when the user panic presses the back button.
+ 0 - Nothing
+ 1 - Go to home
+ -->
+ <integer name="config_backPanicBehavior">0</integer>
+
<!-- Control the behavior when the user short presses the power button.
0 - Nothing
1 - Go to sleep (doze)
diff --git a/core/res/res/values/symbols.xml b/core/res/res/values/symbols.xml
index e97ee8e..45e4520 100644
--- a/core/res/res/values/symbols.xml
+++ b/core/res/res/values/symbols.xml
@@ -375,6 +375,7 @@
<java-symbol type="integer" name="config_immersive_mode_confirmation_panic" />
<java-symbol type="integer" name="config_longPressOnPowerBehavior" />
<java-symbol type="integer" name="config_longPressOnBackBehavior" />
+ <java-symbol type="integer" name="config_backPanicBehavior" />
<java-symbol type="integer" name="config_lowMemoryKillerMinFreeKbytesAdjust" />
<java-symbol type="integer" name="config_lowMemoryKillerMinFreeKbytesAbsolute" />
<java-symbol type="integer" name="config_max_pan_devices" />
diff --git a/packages/SettingsProvider/res/values/defaults.xml b/packages/SettingsProvider/res/values/defaults.xml
index f7e9541..fad102f 100644
--- a/packages/SettingsProvider/res/values/defaults.xml
+++ b/packages/SettingsProvider/res/values/defaults.xml
@@ -155,6 +155,9 @@
<!-- Default for Settings.Secure.LONG_PRESS_TIMEOUT_MILLIS -->
<integer name="def_long_press_timeout_millis">400</integer>
+ <!-- Default for Settings.Secure.MULTI_PRESS_TIMEOUT -->
+ <integer name="def_multi_press_timeout_millis">300</integer>
+
<!-- Default for Settings.Secure.SHOW_IME_WITH_HARD_KEYBOARD -->
<bool name="def_show_ime_with_hard_keyboard">false</bool>
diff --git a/packages/SettingsProvider/src/com/android/providers/settings/SettingsProvider.java b/packages/SettingsProvider/src/com/android/providers/settings/SettingsProvider.java
index d27f1f8..31c5b36 100644
--- a/packages/SettingsProvider/src/com/android/providers/settings/SettingsProvider.java
+++ b/packages/SettingsProvider/src/com/android/providers/settings/SettingsProvider.java
@@ -2090,7 +2090,7 @@
}
private final class UpgradeController {
- private static final int SETTINGS_VERSION = 130;
+ private static final int SETTINGS_VERSION = 131;
private final int mUserId;
@@ -2398,6 +2398,22 @@
currentVersion = 130;
}
+ if (currentVersion == 130) {
+ // Initialize new multi-press timeout to default value
+ final SettingsState systemSecureSettings = getSecureSettingsLocked(userId);
+ final String oldValue = systemSecureSettings.getSettingLocked(
+ Settings.Secure.MULTI_PRESS_TIMEOUT).getValue();
+ if (TextUtils.equals(null, oldValue)) {
+ systemSecureSettings.insertSettingLocked(
+ Settings.Secure.MULTI_PRESS_TIMEOUT,
+ String.valueOf(getContext().getResources().getInteger(
+ R.integer.def_multi_press_timeout_millis)),
+ SettingsState.SYSTEM_PACKAGE_NAME);
+ }
+
+ currentVersion = 131;
+ }
+
if (currentVersion != newVersion) {
Slog.w("SettingsProvider", "warning: upgrading settings database to version "
+ newVersion + " left it at "
diff --git a/services/core/java/com/android/server/am/CoreSettingsObserver.java b/services/core/java/com/android/server/am/CoreSettingsObserver.java
index 9dd07a9..73a17c6 100644
--- a/services/core/java/com/android/server/am/CoreSettingsObserver.java
+++ b/services/core/java/com/android/server/am/CoreSettingsObserver.java
@@ -42,6 +42,7 @@
String, Class<?>>();
static {
sSecureSettingToTypeMap.put(Settings.Secure.LONG_PRESS_TIMEOUT, int.class);
+ sSecureSettingToTypeMap.put(Settings.Secure.MULTI_PRESS_TIMEOUT, int.class);
// add other secure settings here...
sSystemSettingToTypeMap.put(Settings.System.TIME_12_24, String.class);
diff --git a/services/core/java/com/android/server/policy/PhoneWindowManager.java b/services/core/java/com/android/server/policy/PhoneWindowManager.java
index e502764..dcee44f 100644
--- a/services/core/java/com/android/server/policy/PhoneWindowManager.java
+++ b/services/core/java/com/android/server/policy/PhoneWindowManager.java
@@ -200,6 +200,11 @@
static final int MULTI_PRESS_POWER_THEATER_MODE = 1;
static final int MULTI_PRESS_POWER_BRIGHTNESS_BOOST = 2;
+ // Number of presses needed before we induce panic press behavior on the back button
+ static final int PANIC_PRESS_BACK_COUNT = 4;
+ static final int PANIC_PRESS_BACK_NOTHING = 0;
+ static final int PANIC_PRESS_BACK_HOME = 1;
+
// These need to match the documentation/constant in
// core/res/res/values/config.xml
static final int LONG_PRESS_HOME_NOTHING = 0;
@@ -406,6 +411,7 @@
volatile boolean mBackKeyHandled;
volatile boolean mBeganFromNonInteractive;
volatile int mPowerKeyPressCounter;
+ volatile int mBackKeyPressCounter;
volatile boolean mEndCallKeyHandled;
volatile boolean mCameraGestureTriggeredDuringGoingToSleep;
volatile boolean mGoingToSleep;
@@ -464,6 +470,7 @@
int mDoublePressOnPowerBehavior;
int mTriplePressOnPowerBehavior;
int mLongPressOnBackBehavior;
+ int mPanicPressOnBackBehavior;
int mShortPressOnSleepBehavior;
int mShortPressWindowBehavior;
boolean mAwake;
@@ -726,6 +733,7 @@
private static final int MSG_SHOW_TV_PICTURE_IN_PICTURE_MENU = 17;
private static final int MSG_BACK_LONG_PRESS = 18;
private static final int MSG_DISPOSE_INPUT_CONSUMER = 19;
+ private static final int MSG_BACK_DELAYED_PRESS = 20;
private static final int MSG_REQUEST_TRANSIENT_BARS_ARG_STATUS = 0;
private static final int MSG_REQUEST_TRANSIENT_BARS_ARG_NAVIGATION = 1;
@@ -792,10 +800,15 @@
break;
case MSG_BACK_LONG_PRESS:
backLongPress();
+ finishBackKeyPress();
break;
case MSG_DISPOSE_INPUT_CONSUMER:
disposeInputConsumer((InputConsumer) msg.obj);
break;
+ case MSG_BACK_DELAYED_PRESS:
+ backMultiPressAction((Long) msg.obj, msg.arg1);
+ finishBackKeyPress();
+ break;
}
}
}
@@ -1010,6 +1023,52 @@
}
}
+ private void interceptBackKeyDown() {
+ // Reset back key state for long press
+ mBackKeyHandled = false;
+
+ // Cancel multi-press detection timeout.
+ if (hasPanicPressOnBackBehavior()) {
+ if (mBackKeyPressCounter != 0
+ && mBackKeyPressCounter < PANIC_PRESS_BACK_COUNT) {
+ mHandler.removeMessages(MSG_BACK_DELAYED_PRESS);
+ }
+ }
+
+ if (hasLongPressOnBackBehavior()) {
+ Message msg = mHandler.obtainMessage(MSG_BACK_LONG_PRESS);
+ msg.setAsynchronous(true);
+ mHandler.sendMessageDelayed(msg,
+ ViewConfiguration.get(mContext).getDeviceGlobalActionKeyTimeout());
+ }
+ }
+
+ // returns true if the key was handled and should not be passed to the user
+ private boolean interceptBackKeyUp(KeyEvent event) {
+ // Cache handled state
+ boolean handled = mBackKeyHandled;
+
+ if (hasPanicPressOnBackBehavior()) {
+ // Check for back key panic press
+ ++mBackKeyPressCounter;
+
+ final long eventTime = event.getDownTime();
+
+ if (mBackKeyPressCounter <= PANIC_PRESS_BACK_COUNT) {
+ // This could be a multi-press. Wait a little bit longer to confirm.
+ Message msg = mHandler.obtainMessage(MSG_BACK_DELAYED_PRESS,
+ mBackKeyPressCounter, 0, eventTime);
+ msg.setAsynchronous(true);
+ mHandler.sendMessageDelayed(msg, ViewConfiguration.getMultiPressTimeout());
+ }
+ }
+
+ // Reset back long press state
+ cancelPendingBackKeyAction();
+
+ return handled;
+ }
+
private void interceptPowerKeyDown(KeyEvent event, boolean interactive) {
// Hold a wake lock until the power key is released.
if (!mPowerKeyWakeLock.isHeld()) {
@@ -1140,6 +1199,10 @@
}
}
+ private void finishBackKeyPress() {
+ mBackKeyPressCounter = 0;
+ }
+
private void cancelPendingPowerKeyAction() {
if (!mPowerKeyHandled) {
mPowerKeyHandled = true;
@@ -1154,6 +1217,18 @@
}
}
+ private void backMultiPressAction(long eventTime, int count) {
+ if (count >= PANIC_PRESS_BACK_COUNT) {
+ switch (mPanicPressOnBackBehavior) {
+ case PANIC_PRESS_BACK_NOTHING:
+ break;
+ case PANIC_PRESS_BACK_HOME:
+ launchHomeFromHotKey();
+ break;
+ }
+ }
+ }
+
private void powerPress(long eventTime, boolean interactive, int count) {
if (mScreenOnEarly && !mScreenOnFully) {
Slog.i(TAG, "Suppressed redundant power key press while "
@@ -1312,6 +1387,10 @@
return mLongPressOnBackBehavior != LONG_PRESS_BACK_NOTHING;
}
+ private boolean hasPanicPressOnBackBehavior() {
+ return mPanicPressOnBackBehavior != PANIC_PRESS_BACK_NOTHING;
+ }
+
private void interceptScreenshotChord() {
if (mScreenshotChordEnabled
&& mScreenshotChordVolumeDownKeyTriggered && mScreenshotChordPowerKeyTriggered
@@ -1639,6 +1718,8 @@
mLongPressOnBackBehavior = mContext.getResources().getInteger(
com.android.internal.R.integer.config_longPressOnBackBehavior);
+ mPanicPressOnBackBehavior = mContext.getResources().getInteger(
+ com.android.internal.R.integer.config_backPanicBehavior);
mShortPressOnPowerBehavior = mContext.getResources().getInteger(
com.android.internal.R.integer.config_shortPressOnPowerBehavior);
@@ -5607,20 +5688,11 @@
switch (keyCode) {
case KeyEvent.KEYCODE_BACK: {
if (down) {
- mBackKeyHandled = false;
- if (hasLongPressOnBackBehavior()) {
- Message msg = mHandler.obtainMessage(MSG_BACK_LONG_PRESS);
- msg.setAsynchronous(true);
- mHandler.sendMessageDelayed(msg,
- ViewConfiguration.get(mContext).getDeviceGlobalActionKeyTimeout());
- }
+ interceptBackKeyDown();
} else {
- boolean handled = mBackKeyHandled;
+ boolean handled = interceptBackKeyUp(event);
- // Reset back key state
- cancelPendingBackKeyAction();
-
- // Don't pass back press to app if we've already handled it
+ // Don't pass back press to app if we've already handled it via long press
if (handled) {
result &= ~ACTION_PASS_TO_USER;
}
