added clear input pin button

src/trezor/ui/button.py

@@ -1,5 +1,5 @@
 from . import display, in_area, rotate_coords
-from trezor import ui, loop
+from trezor import ui, loop, res
 
 
 DEFAULT_BUTTON = {
@@ -41,6 +41,19 @@ CONFIRM_BUTTON_ACTIVE = {
     'border-color': ui.GREEN,
 }
 
+CLEAR_BUTTON = {
+    'bg-color': ui.BLACK,
+    'fg-color': ui.WHITE,
+    'text-style': ui.NORMAL,
+    'border-color': ui.BLACK,    
+}
+CLEAR_BUTTON_ACTIVE = {
+    'bg-color': ui.BLACK,
+    'fg-color': ui.WHITE,
+    'text-style': ui.NORMAL,
+    'border-color': ui.BLACK,
+}
+
 BTN_CLICKED = const(1)
 
 BTN_STARTED = const(1)
@@ -68,10 +81,16 @@ class Button():
         ty = ay + ah // 2 + 8
         display.bar(ax, ay, aw, ah, style['border-color'])
         display.bar(ax + 1, ay + 1, aw - 2, ah - 2, style['bg-color'])
-        display.text_center(tx, ty, self.text,
-                            style['text-style'],
-                            style['fg-color'],
-                            style['bg-color'])
+        # How to do this smarter way?
+        if self.text == 'CLEAR':
+            ui.display.icon(ax, ay, res.load('trezor/res/close-button.toig'),
+                                ui.blend(ui.BLACK, ui.WHITE, 0.95),
+                                ui.BLACK)
+        else:
+            display.text_center(tx, ty, self.text,
+                                style['text-style'],
+                                style['fg-color'],
+                                style['bg-color'])
         self.state = state
 
     def send(self, event, pos):

src/trezor/ui/pin.py

@@ -5,6 +5,7 @@ from .button import Button, BTN_CLICKED
 from .button import CONFIRM_BUTTON, CONFIRM_BUTTON_ACTIVE
 from .button import CANCEL_BUTTON, CANCEL_BUTTON_ACTIVE
 
+
 def digit_area(i):
     width = const(80)
     height = const(48)
@@ -24,7 +25,7 @@ class PinMatrix():
     def __init__(self, label='Enter PIN', pin=''):
         self.label = label
         self.pin = pin
-        self.clear_button = Button((240 - 48, 0, 48, 42), 'X')
+        self.clear_button = Button((240 - 35, 5, 30, 30), 'CLEAR')
         self.buttons = [Button(digit_area(i), str(d))
                         for i, d in enumerate(generate_digits())]
 
@@ -58,6 +59,7 @@ class PinMatrix():
         if self.clear_button.send(event, pos) == BTN_CLICKED:
             self.pin = ''
             self.label = 'Enter PIN'
+            display.bar(240 - 48, 0, 48, 42, ui.BLACK)
 
 
         for btn in self.buttons: