recovery: Implement sysbar

Add a system bar (navigation bar) similar to the main Android system
with back and home buttons.  This makes it easier for users to figure
out how to go back on devices that lack hardware buttons, and also
provides a quick way to get back to the main menu.

Note only buttons that do not have a hardware equivalent are shown, in
order to prevent redundancy and confusion.

Change-Id: I7538749978837571a8c250c3c8e54ac127b39d84

1 files changed, 28 insertions, 1 deletions

diff --git a/ui.cpp b/ui.cpp
index 1594580..14f92b4 100644
--- a/ui.cpp
+++ b/ui.cpp
@@ -144,7 +144,9 @@ RecoveryUI::RecoveryUI()
           last_key(-1),
           has_power_key(false),
           has_up_key(false),
-          has_down_key(false) {
+          has_down_key(false),
+          has_back_key(false),
+          has_home_key(false) {
     pthread_mutex_init(&key_queue_mutex, nullptr);
     pthread_cond_init(&key_queue_cond, nullptr);
     memset(key_pressed, 0, sizeof(key_pressed));
@@ -157,6 +159,12 @@ void RecoveryUI::OnKeyDetected(int key_code) {
         has_down_key = true;
     } else if (key_code == KEY_UP || key_code == KEY_VOLUMEUP) {
         has_up_key = true;
+    } else if (key_code == KEY_BACK) {
+        has_back_key = true;
+        LOGI("Detected back key, disabling virtual back button\n");
+    } else if (key_code == KEY_HOMEPAGE) {
+        has_home_key = true;
+        LOGI("Detected home key, disabling virtual home button\n");
     }
 }
 
@@ -566,6 +574,12 @@ void RecoveryUI::handle_press(input_device* dev) {
     dev->touch_start = dev->touch_track = dev->touch_pos;
     dev->in_touch = true;
     dev->in_swipe = false;
+    if (dev->touch_pos.y >= gr_fb_height() - GetSysbarHeight()) {
+        SetSysbarState(1 << (3 * dev->touch_pos.x / gr_fb_width()));
+    }
+    else {
+        SetSysbarState(0);
+    }
 }
 
 void RecoveryUI::handle_release(input_device* dev) {
@@ -588,6 +602,19 @@ void RecoveryUI::handle_release(input_device* dev) {
                 return;
             }
         }
+
+        int sysbar_state = GetSysbarState();
+        SetSysbarState(0);
+        if (sysbar_state == 0x01) {
+            ProcessKey(dev, KEY_BACK, 1);
+            ProcessKey(dev, KEY_BACK, 0);
+            return;
+        }
+        if (sysbar_state == 0x02) {
+            ProcessKey(dev, KEY_HOME, 1);
+            ProcessKey(dev, KEY_HOME, 0);
+            return;
+        }
     }
 
     if (DialogShowing()) {