Allow to obtain virtual keyboard height

On mobile platforms virtual keyboards take up significant amount of
screen space and UI containing a text box may need to be adjusted
after the keyboard appears to keep the text box visible to user. This
commit adds a way to obtain virtual keyabord height so that controls
are aware of how much they need to move.

4 files changed, 55 insertions, 0 deletions

diff --git a/platform/iphone/gl_view.h b/platform/iphone/gl_view.h
index a9fd8d5711..f7309396c6 100644
--- a/platform/iphone/gl_view.h
+++ b/platform/iphone/gl_view.h
@@ -100,6 +100,8 @@
 - (void)destroyFramebuffer;
 
 - (void)audioRouteChangeListenerCallback:(NSNotification *)notification;
+- (void)keyboardOnScreen:(NSNotification *)notification;
+- (void)keyboardHidden:(NSNotification *)notification;
 
 @property NSTimeInterval animationInterval;
 @property(nonatomic, assign) BOOL useCADisplayLink;
diff --git a/platform/iphone/gl_view.mm b/platform/iphone/gl_view.mm
index 3e206c3a2c..02da706cc5 100644
--- a/platform/iphone/gl_view.mm
+++ b/platform/iphone/gl_view.mm
@@ -63,6 +63,7 @@ void _pause_video();
 void _focus_out_video();
 void _unpause_video();
 void _stop_video();
+CGFloat _points_to_pixels(CGFloat);
 
 void _show_keyboard(String p_existing) {
 	keyboard_text = p_existing;
@@ -174,6 +175,19 @@ void _stop_video() {
 	video_playing = false;
 }
 
+CGFloat _points_to_pixels(CGFloat points) {
+	float pixelPerInch;
+	if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad) {
+		pixelPerInch = 132;
+	} else if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPhone) {
+		pixelPerInch = 163;
+	} else {
+		pixelPerInch = 160;
+	}
+	CGFloat pointsPerInch = 72.0;
+	return (points / pointsPerInch * pixelPerInch);
+}
+
 @implementation GLView
 
 @synthesize animationInterval;
@@ -537,6 +551,20 @@ static void clear_touches() {
 	[self resignFirstResponder];
 };
 
+- (void)keyboardOnScreen:(NSNotification *)notification {
+	NSDictionary *info = notification.userInfo;
+	NSValue *value = info[UIKeyboardFrameEndUserInfoKey];
+
+	CGRect rawFrame = [value CGRectValue];
+	CGRect keyboardFrame = [self convertRect:rawFrame fromView:nil];
+
+	OSIPhone::get_singleton()->set_virtual_keyboard_height(_points_to_pixels(keyboardFrame.size.height));
+}
+
+- (void)keyboardHidden:(NSNotification *)notification {
+	OSIPhone::get_singleton()->set_virtual_keyboard_height(0);
+}
+
 - (void)deleteBackward {
 	if (keyboard_text.length())
 		keyboard_text.erase(keyboard_text.length() - 1, 1);
@@ -606,6 +634,18 @@ static void clear_touches() {
 				   name:AVAudioSessionRouteChangeNotification
 				 object:nil];
 
+	printf("******** adding observer for keyboard show/hide\n");
+	[[NSNotificationCenter defaultCenter]
+			addObserver:self
+			   selector:@selector(keyboardOnScreen:)
+				   name:UIKeyboardDidShowNotification
+				 object:nil];
+	[[NSNotificationCenter defaultCenter]
+			addObserver:self
+			   selector:@selector(keyboardHidden:)
+				   name:UIKeyboardDidHideNotification
+				 object:nil];
+
 	//self.autoresizesSubviews = YES;
 	//[self setAutoresizingMask:UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleWidth];
 
diff --git a/platform/iphone/os_iphone.cpp b/platform/iphone/os_iphone.cpp
index 5009f7d8ae..219e93facf 100644
--- a/platform/iphone/os_iphone.cpp
+++ b/platform/iphone/os_iphone.cpp
@@ -463,6 +463,14 @@ void OSIPhone::hide_virtual_keyboard() {
 	_hide_keyboard();
 };
 
+void OSIPhone::set_virtual_keyboard_height(int p_height) {
+	virtual_keyboard_height = p_height;
+}
+
+int OSIPhone::get_virtual_keyboard_height() const {
+	return virtual_keyboard_height;
+}
+
 Error OSIPhone::shell_open(String p_uri) {
 	return _shell_open(p_uri);
 };
@@ -576,6 +584,7 @@ OSIPhone::OSIPhone(int width, int height) {
 	vm.resizable = false;
 	set_video_mode(vm);
 	event_count = 0;
+	virtual_keyboard_height = 0;
 
 	_set_logger(memnew(SyslogLogger));
 };
diff --git a/platform/iphone/os_iphone.h b/platform/iphone/os_iphone.h
index 11f4eed5e7..cf2396e87b 100644
--- a/platform/iphone/os_iphone.h
+++ b/platform/iphone/os_iphone.h
@@ -124,6 +124,8 @@ private:
 
 	InputDefault *input;
 
+	int virtual_keyboard_height;
+
 public:
 	bool iterate();
 
@@ -133,6 +135,7 @@ public:
 	void mouse_move(int p_idx, int p_prev_x, int p_prev_y, int p_x, int p_y, bool p_use_as_mouse);
 	void touches_cancelled();
 	void key(uint32_t p_key, bool p_pressed);
+	void set_virtual_keyboard_height(int p_height);
 
 	int set_base_framebuffer(int p_fb);
 
@@ -168,6 +171,7 @@ public:
 	virtual bool has_virtual_keyboard() const;
 	virtual void show_virtual_keyboard(const String &p_existing_text, const Rect2 &p_screen_rect = Rect2());
 	virtual void hide_virtual_keyboard();
+	virtual int get_virtual_keyboard_height() const;
 
 	virtual void set_cursor_shape(CursorShape p_shape);