Fix issue with duplicate messages in the console.

This started happening when I started piping the console streams to the original
standard out/error in fb4bceb. On my phone at least, it can get into a situation
where APDE restarts without, it seems, restarting the JVM. The result is that the
new console stream pipes into the old one and the messages show up twice. Repeat
and now they show up three times, etc. Fixed by disabling the old console streams
when the main activity is destroyed.

APDE/src/main/java/com/calsignlabs/apde/EditorActivity.java

@@ -187,8 +187,8 @@ public class EditorActivity extends AppCompatActivity {
 	private int message = -1;
 
 	//Custom output / error streams for printing to the console
-	private PrintStream outStream;
-	private PrintStream errStream;
+	private ConsoleStream outStream;
+	private ConsoleStream errStream;
 	protected AtomicBoolean FLAG_SUSPEND_OUT_STREAM = new AtomicBoolean(false);
 
 	//Recieve log / console output from sketches
@@ -274,12 +274,12 @@ public void onCreate(Bundle savedInstanceState) {
 		setSupportActionBar(toolbar);
 
 		// Create custom output / error streams for the console
-		outStream = new PrintStream(new ConsoleStream(System.out));
-		errStream = new PrintStream(new ConsoleStream(System.err));
+		outStream = new ConsoleStream(System.out);
+		errStream = new ConsoleStream(System.err);
 
 		// Set the custom output / error streams
-		System.setOut(outStream);
-		System.setErr(errStream);
+		System.setOut(new PrintStream(outStream));
+		System.setErr(new PrintStream(errStream));
 
 		// Initialize log / console receiver
 		consoleBroadcastReceiver = new BroadcastReceiver() {
@@ -1845,8 +1845,15 @@ public void onStop() {
 
 	@Override
 	public void onDestroy() {
-		//Unregister the log / console receiver
-    	unregisterReceiver(consoleBroadcastReceiver);
+		// Unregister the log / console receiver
+		unregisterReceiver(consoleBroadcastReceiver);
+
+		// Stop the print streams. It seems like sometimes the app gets destroyed without restarting
+		// the JVM, and in this situation we start piping the new console streams into the old one;
+		// the result is duplicated messages in the console. We avoid this by preventing console
+		// streams in destroyed activity from displaying their output.
+		outStream.disable();
+		errStream.disable();
 
 		getGlobalState().writeCodeDeletionDebugStatus("onDestroy()");
 
@@ -4809,9 +4816,15 @@ public boolean onLongClick(View view) {
 	private class ConsoleStream extends OutputStream {
 		final byte single[] = new byte[1];
 		private OutputStream pipeTo;
+		private boolean enabled;
 
 		public ConsoleStream(OutputStream pipeTo) {
 			this.pipeTo = pipeTo;
+			this.enabled = true;
+		}
+
+		public void disable() {
+			enabled = false;
 		}
 
 		public void close() { }
@@ -4824,23 +4837,25 @@ public void write(byte b[]) {
 
 		@Override
 		public void write(byte b[], int offset, int length) {
-			// Also pipe output
-			try {
-				pipeTo.write(b, offset, length);
-			} catch (IOException e) {
-				// shrug
-			}
-
-			final String value = new String(b, offset, length);
-
-			if (!(FLAG_SUSPEND_OUT_STREAM.get() &&
-					!PreferenceManager.getDefaultSharedPreferences(EditorActivity.this)
-							.getBoolean("pref_debug_global_verbose_output", false))) {
+			if (enabled) {
+				// Also pipe output
+				try {
+					pipeTo.write(b, offset, length);
+				} catch (IOException e) {
+					// shrug
+				}
 
-				runOnUiThread(() -> {
-					//	Write the value to the console
-					postConsole(value);
-				});
+				final String value = new String(b, offset, length);
+
+				if (!(FLAG_SUSPEND_OUT_STREAM.get() &&
+						!PreferenceManager.getDefaultSharedPreferences(EditorActivity.this)
+								.getBoolean("pref_debug_global_verbose_output", false))) {
+
+					runOnUiThread(() -> {
+						//Write the value to the console
+						postConsole(value);
+					});
+				}
 			}
 		}