Make sticky modifiers an option, off by default.

Users with near-full-size keyboards (tablet docks/cases, or usb/bluetooth
keyboards) probably don't want sticky modifier keys. Make it an option
that's off by default (except on the Dream where it's likely desirable).
Also, include a third state to make only "alt" sticky, for the benefit of
the crazy keyboard driver on the TF101/201 that doesn't emit real key
events for alt+key pressed together.

Also, implement stickiness for the control key on physical keyboards that
have one, for consistency.

7 files changed, 67 insertions, 5 deletions

diff --git a/res/values/arrays.xml b/res/values/arrays.xml
index 00c92ba..4721490 100644
--- a/res/values/arrays.xml
+++ b/res/values/arrays.xml
@@ -71,6 +71,18 @@
 		<item>gray</item>
 	</string-array>
 
+	<string-array name="list_stickymodifiers" translatable="false">
+		<item>@string/no</item>
+		<item>@string/only_alt</item>
+		<item>@string/yes</item>
+	</string-array>
+
+	<string-array name="list_stickymodifiers_values" translatable="false">
+		<item>no</item>
+		<item>alt</item>
+		<item>yes</item>
+	</string-array>
+
 	<string-array name="list_keymode" translatable="false">
 		<item>@string/list_keymode_right</item>
 		<item>@string/list_keymode_left</item>
diff --git a/res/values/strings.xml b/res/values/strings.xml
index 273815b..e634385 100644
--- a/res/values/strings.xml
+++ b/res/values/strings.xml
@@ -196,6 +196,13 @@
 	<!-- Summary for the keyboard shortcuts preference -->
 	<string name="pref_keymode_summary">"Select how to use Alt for '/' and Shift for Tab"</string>
 
+	<!-- Name for the sticky modifiers preference -->
+	<string name="pref_stickymodifiers_title">"Sticky modifiers"</string>
+	<!-- Summary for the sticky modifiers preference -->
+	<string name="pref_stickymodifiers_summary">"Modifier keys remain enabled until another key is pressed"</string>
+
+	<string name="only_alt">"Only alt"</string>
+
 	<!-- Name for the camera shortcut usage preference -->
 	<string name="pref_camera_title">"Camera shortcut"</string>
 	<!-- Summary for the camera shortcut usage preference -->
diff --git a/res/xml/preferences.xml b/res/xml/preferences.xml
index 6d20a5d..a1b79ae 100644
--- a/res/xml/preferences.xml
+++ b/res/xml/preferences.xml
@@ -122,6 +122,15 @@
 			/>
 
 		<ListPreference
+			android:key="stickymodifiers"
+			android:title="@string/pref_stickymodifiers_title"
+			android:summary="@string/pref_stickymodifiers_summary"
+			android:entries="@array/list_stickymodifiers"
+			android:entryValues="@array/list_stickymodifiers_values"
+			android:defaultValue="no"
+			/>
+
+		<ListPreference
 			android:key="keymode"
 			android:title="@string/pref_keymode_title"
 			android:summary="@string/pref_keymode_summary"
diff --git a/src/org/connectbot/ConsoleActivity.java b/src/org/connectbot/ConsoleActivity.java
index 7aca08c..aeb0e67 100644
--- a/src/org/connectbot/ConsoleActivity.java
+++ b/src/org/connectbot/ConsoleActivity.java
@@ -422,7 +422,7 @@ public class ConsoleActivity extends Activity {
 				TerminalView terminal = (TerminalView)flip;
 
 				TerminalKeyListener handler = terminal.bridge.getKeyHandler();
-				handler.metaPress(TerminalKeyListener.OUR_CTRL_ON);
+				handler.metaPress(TerminalKeyListener.OUR_CTRL_ON, true);
 				hideEmulatedKeys();
 			}
 		});
diff --git a/src/org/connectbot/HostListActivity.java b/src/org/connectbot/HostListActivity.java
index 648b705..99c2a39 100644
--- a/src/org/connectbot/HostListActivity.java
+++ b/src/org/connectbot/HostListActivity.java
@@ -172,6 +172,11 @@ public class HostListActivity extends ListActivity {
 				editor.putBoolean(PreferenceConstants.CTRL_FKEYS, true);
 				editor.commit();
 			}
+			if (!prefs.contains(PreferenceConstants.STICKY_MODIFIERS)) {
+				SharedPreferences.Editor editor = prefs.edit();
+				editor.putString(PreferenceConstants.STICKY_MODIFIERS, PreferenceConstants.YES);
+				editor.commit();
+			}
 		}
 
 		// check for eula agreement
diff --git a/src/org/connectbot/service/TerminalKeyListener.java b/src/org/connectbot/service/TerminalKeyListener.java
index 43bd8e0..fc3413d 100644
--- a/src/org/connectbot/service/TerminalKeyListener.java
+++ b/src/org/connectbot/service/TerminalKeyListener.java
@@ -64,6 +64,8 @@ public class TerminalKeyListener implements OnKeyListener, OnSharedPreferenceCha
 
 	// backport constants from api level 11
 	private final static int KEYCODE_ESCAPE = 111;
+	private final static int KEYCODE_CTRL_LEFT = 113;
+	private final static int KEYCODE_CTRL_RIGHT = 114;
 	private final static int HC_META_CTRL_ON = 0x1000;
 	private final static int HC_META_CTRL_LEFT_ON = 0x2000;
 	private final static int HC_META_CTRL_RIGHT_ON = 0x4000;
@@ -81,6 +83,7 @@ public class TerminalKeyListener implements OnKeyListener, OnSharedPreferenceCha
 	private boolean shiftedNumbersAreFKeysOnHardKeyboard;
 	private boolean controlNumbersAreFKeysOnSoftKeyboard;
 	private boolean volumeKeysChangeFontSize;
+	private int stickyMetas;
 
 	private int ourMetaState = 0;
 
@@ -234,6 +237,10 @@ public class TerminalKeyListener implements OnKeyListener, OnSharedPreferenceCha
 						return true;
 					}
 				}
+				if (keyCode == KEYCODE_CTRL_LEFT || keyCode == KEYCODE_CTRL_RIGHT) {
+					metaPress(OUR_CTRL_ON);
+					return true;
+				}
 			}
 
 			if (keyCode == KeyEvent.KEYCODE_DPAD_CENTER) {
@@ -258,7 +265,7 @@ public class TerminalKeyListener implements OnKeyListener, OnSharedPreferenceCha
 						sendEscape();
 						ourMetaState &= ~OUR_CTRL_ON;
 					} else
-						metaPress(OUR_CTRL_ON);
+						metaPress(OUR_CTRL_ON, true);
 				}
 				bridge.redraw();
 				return true;
@@ -497,17 +504,25 @@ public class TerminalKeyListener implements OnKeyListener, OnSharedPreferenceCha
 	 *
 	 * @param code
 	 */
-	public void metaPress(int code) {
+	public void metaPress(int code, boolean forceSticky) {
 		if ((ourMetaState & (code << 1)) != 0) {
 			ourMetaState &= ~(code << 1);
 		} else if ((ourMetaState & code) != 0) {
 			ourMetaState &= ~code;
 			ourMetaState |= code << 1;
-		} else
+		} else if (forceSticky || (stickyMetas & code) != 0) {
 			ourMetaState |= code;
+		} else {
+			// skip redraw
+			return;
+		}
 		bridge.redraw();
 	}
 
+	public void metaPress(int code) {
+		metaPress(code, false);
+	}
+
 	public void setTerminalKeyMode(String keymode) {
 		this.keymode = keymode;
 	}
@@ -542,7 +557,8 @@ public class TerminalKeyListener implements OnKeyListener, OnSharedPreferenceCha
 		if (PreferenceConstants.KEYMODE.equals(key) ||
 		    PreferenceConstants.SHIFT_FKEYS.equals(key) ||
 		    PreferenceConstants.CTRL_FKEYS.equals(key) ||
-		    PreferenceConstants.VOLUME_FONT.equals(key)) {
+		    PreferenceConstants.VOLUME_FONT.equals(key) ||
+		    PreferenceConstants.STICKY_MODIFIERS.equals(key)) {
 			updatePrefs();
 		}
 	}
@@ -554,6 +570,15 @@ public class TerminalKeyListener implements OnKeyListener, OnSharedPreferenceCha
 		controlNumbersAreFKeysOnSoftKeyboard =
 				prefs.getBoolean(PreferenceConstants.CTRL_FKEYS, false);
 		volumeKeysChangeFontSize = prefs.getBoolean(PreferenceConstants.VOLUME_FONT, true);
+		String stickyModifiers = prefs.getString(PreferenceConstants.STICKY_MODIFIERS,
+		                                         PreferenceConstants.NO);
+		if (PreferenceConstants.ALT.equals(stickyModifiers)) {
+			stickyMetas = OUR_ALT_ON;
+		} else if (PreferenceConstants.YES.equals(stickyModifiers)) {
+			stickyMetas = OUR_SHIFT_ON | OUR_CTRL_ON | OUR_ALT_ON;
+		} else {
+			stickyMetas = 0;
+		}
 	}
 
 	public void setCharset(String encoding) {
diff --git a/src/org/connectbot/util/PreferenceConstants.java b/src/org/connectbot/util/PreferenceConstants.java
index ade1b35..ab5e4a9 100644
--- a/src/org/connectbot/util/PreferenceConstants.java
+++ b/src/org/connectbot/util/PreferenceConstants.java
@@ -80,6 +80,10 @@ public class PreferenceConstants {
 	public static final String SHIFT_FKEYS = "shiftfkeys";
 	public static final String CTRL_FKEYS = "ctrlfkeys";
 	public static final String VOLUME_FONT = "volumefont";
+	public static final String STICKY_MODIFIERS = "stickymodifiers";
+	public static final String YES = "yes";
+	public static final String NO = "no";
+	public static final String ALT = "alt";
 
 	/* Backup identifiers */
 	public static final String BACKUP_PREF_KEY = "prefs";