java: Refactor AltosFlightDisplay units and font update handling

Make AltosFlightDisplay explicitly implement AltosFontListener and
AltosUnitsListener interfaces to make everyone use the same API. Then,
actually go implement units listeners so that changing units updates
all of the active displays immediately

Signed-off-by: Keith Packard <keithp@keithp.com>

1 files changed, 1 insertions, 3 deletions

diff --git a/altosuilib/AltosFlightDisplay.java b/altosuilib/AltosFlightDisplay.java
index 5695a015..5fb0cab7 100644
--- a/altosuilib/AltosFlightDisplay.java
+++ b/altosuilib/AltosFlightDisplay.java
@@ -19,10 +19,8 @@ package org.altusmetrum.altosuilib_2;
 
 import org.altusmetrum.altoslib_4.*;
 
-public interface AltosFlightDisplay {
+public interface AltosFlightDisplay extends AltosUnitsListener, AltosFontListener {
 	void reset();
 
 	void show(AltosState state, AltosListenerState listener_state);
-
-	void set_font();
 }