altosui/telegps: Display error message when attempting to graph unknown files

Instead of presenting an empty graph window.

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

1 files changed, 4 insertions, 0 deletions

diff --git a/altoslib/AltosEepromFile.java b/altoslib/AltosEepromFile.java
index 839f0aa0..328a0fab 100644
--- a/altoslib/AltosEepromFile.java
+++ b/altoslib/AltosEepromFile.java
@@ -45,6 +45,10 @@ public class AltosEepromFile implements AltosRecordSet {
 		return set.cal_data();
 	}
 
+	public boolean valid() {
+		return set.valid();
+	}
+
 	public void capture_series(AltosDataListener series) {
 		set.capture_series(series);
 	}