use alerts, rather than toasts in FriendlyHttpResponseHandler

If notifications are disabled for an application, toasts are also
squelched, leaving important error messages on the floor.

One possible thing to look out for is that you currently pass a single
Context to the handler.  Previously, you could use the application's
context.  This meant if you got the async response when viewing another
activity, it could still be handled as the application Context still
existed.  Now, you have to use an activity's context, which means if the
response returns when viewing another activity, you'll get an exception.

A workaround would be to use 2 contexts, one for the application to
handle the response at all costs, and another for the activity to
display the error when possible (if the activity still exists).  We'll
see if that's necessary...

Author: jamur2

src/com/loopj/android/http/FriendlyHttpResponseHandler.java

@@ -4,8 +4,8 @@
  dispatches to appropriate success and failure handlers.
 
  Also, default error handlers provide noisy error messages to users by default,
- rather than doing nothing.  eg., if the server goes down, pop up a Toast saying
- as much rather than calling an empty error handler.
+ rather than doing nothing.  eg., if the server goes down, pop up a dialog
+ saying as much rather than calling an empty error handler.
 
  */
 
@@ -18,9 +18,9 @@
 import org.json.JSONObject;
 import org.json.JSONTokener;
 
+import android.app.AlertDialog;
 import android.content.Context;
-
-import android.widget.Toast;
+import android.content.DialogInterface;
 
 public class FriendlyHttpResponseHandler extends
         com.loopj.android.http.AsyncHttpResponseHandler {
@@ -35,9 +35,19 @@ public FriendlyHttpResponseHandler(Context startContext) {
     @Override
     public void onFailure(Throwable e) {
         String errorDescription = "An unknown error occurred.";
-        Toast toast = Toast.makeText(context, errorDescription,
-                Toast.LENGTH_SHORT);
-        toast.show();
+        AlertDialog.Builder builder = new AlertDialog.Builder(
+            context);
+        builder.setTitle("Alert");
+        builder.setMessage(errorDescription);
+        builder.setPositiveButton("OK",
+            new DialogInterface.OnClickListener() {
+                @Override
+                public void onClick(DialogInterface dialog,
+                        int which) {
+                    dialog.dismiss();
+                }
+            });
+        builder.create().show();
     }
 
     public void onFailure(Throwable e, JSONObject errorResponse) {
@@ -49,23 +59,53 @@ public void onFailure(Throwable e, JSONObject errorResponse) {
         } catch (JSONException e1) {
             e1.printStackTrace();
         }
-        Toast toast = Toast.makeText(context, errorDescription,
-                Toast.LENGTH_SHORT);
-        toast.show();
+        AlertDialog.Builder builder = new AlertDialog.Builder(
+            context);
+        builder.setTitle("Alert");
+        builder.setMessage(errorDescription);
+        builder.setPositiveButton("OK",
+            new DialogInterface.OnClickListener() {
+                @Override
+                public void onClick(DialogInterface dialog,
+                        int which) {
+                    dialog.dismiss();
+                }
+            });
+        builder.create().show();
     }
 
     @Override
     public void onFailure(Throwable e, String errorResponse) {
-        Toast toast = Toast
-                .makeText(context, errorResponse, Toast.LENGTH_SHORT);
-        toast.show();
+        AlertDialog.Builder builder = new AlertDialog.Builder(
+            context);
+        builder.setTitle("Alert");
+        builder.setMessage(errorResponse);
+        builder.setPositiveButton("OK",
+            new DialogInterface.OnClickListener() {
+                @Override
+                public void onClick(DialogInterface dialog,
+                        int which) {
+                    dialog.dismiss();
+                }
+            });
+        builder.create().show();
     }
 
     public void onFailure(Throwable e, JSONArray errorResponse) {
         String errorDescription = "An unknown error occurred.";
-        Toast toast = Toast.makeText(context, errorDescription,
-                Toast.LENGTH_SHORT);
-        toast.show();
+        AlertDialog.Builder builder = new AlertDialog.Builder(
+            context);
+        builder.setTitle("Alert");
+        builder.setMessage(errorDescription);
+        builder.setPositiveButton("OK",
+            new DialogInterface.OnClickListener() {
+                @Override
+                public void onClick(DialogInterface dialog,
+                        int which) {
+                    dialog.dismiss();
+                }
+            });
+        builder.create().show();
     }
 
     public void onSuccess(JSONObject response) {
@@ -161,3 +201,4 @@ protected Object parseResponse(String responseBody) throws JSONException {
         return result;
     }
 }
+