Adding a utility function to call external functions from gwt without writing jsni

3 files changed, 50 insertions, 5 deletions

diff --git a/gwtquery-core/src/main/java/com/google/gwt/query/client/js/JsObjectArray.java b/gwtquery-core/src/main/java/com/google/gwt/query/client/js/JsObjectArray.java
index 1e8cf6a6..9eac0d79 100644
--- a/gwtquery-core/src/main/java/com/google/gwt/query/client/js/JsObjectArray.java
+++ b/gwtquery-core/src/main/java/com/google/gwt/query/client/js/JsObjectArray.java
@@ -33,14 +33,22 @@ public final class JsObjectArray<T> extends JavaScriptObject {
     return cast();
   }
 
-  public void add(T...vals) {
+  public JsObjectArray<T> add(T...vals) {
     for (T t: vals) {
-      c().put(length(), t);
+      if (t instanceof Number) {
+        c().putNumber(length(), (((Number)t).doubleValue()));
+      } else if (t instanceof Boolean) {
+        c().putBoolean(length(), ((Boolean)t).booleanValue());
+      } else {
+        c().put(length(), t);
+      }
     }
+    return this;
   }
 
-  public void add(int i, T val) {
+  public JsObjectArray<T> add(int i, T val) {
     c().put(i, val);
+    return this;
   }
 
   @SuppressWarnings("unchecked")
diff --git a/gwtquery-core/src/main/java/com/google/gwt/query/client/js/JsUtils.java b/gwtquery-core/src/main/java/com/google/gwt/query/client/js/JsUtils.java
index b24fe2eb..974462db 100644
--- a/gwtquery-core/src/main/java/com/google/gwt/query/client/js/JsUtils.java
+++ b/gwtquery-core/src/main/java/com/google/gwt/query/client/js/JsUtils.java
@@ -18,6 +18,7 @@ package com.google.gwt.query.client.js;
 import com.google.gwt.core.client.GWT;
 import com.google.gwt.core.client.JavaScriptObject;
 import com.google.gwt.core.client.JsArray;
+import com.google.gwt.core.client.JsArrayMixed;
 import com.google.gwt.dom.client.Document;
 import com.google.gwt.dom.client.Element;
 import com.google.gwt.dom.client.Node;
@@ -316,8 +317,7 @@ public class JsUtils {
    * Check is a javascript object is a function
    */
   public static native boolean isFunction(JavaScriptObject o) /*-{
-    var r = Object.prototype.toString.call(o);
-    return r == '[object Function]';
+    return Object.prototype.toString.call(o) == '[object Function]';
   }-*/;
 
   /**
@@ -399,6 +399,33 @@ public class JsUtils {
   public static String text(Element e) {
     return utilsImpl.text(e);
   }
+  
+  /**
+   * Call via jsni any arbitrary function present in a Javascript object.
+   * 
+   * It's thought for avoiding to create jsni methods to call external functions and
+   * facilitate the writing of js wrappers.
+   * 
+   * Example
+   * <pre>
+   *  // Create a svg node in our document.
+   *  Element svg = runJavascriptFunction(document, "createElementNS", "http://www.w3.org/2000/svg", "svg");
+   *  // Append it to the dom
+   *  $(svg).appendTo(document);
+   * </pre>
+   * 
+   * @param o  the javascript object where the function is.
+   * @param meth the literal name of the function to call.
+   * @param args an array with the arguments to pass to the function.
+   * @return the javascript object returned by the jsni method or null.
+   */
+  public static <T> T runJavascriptFunction(JavaScriptObject o, String meth, Object... args) {
+    return runJavascriptFunctionImpl(o, meth, JsObjectArray.create().add(args).<JsArrayMixed>cast());
+  }
+  
+  private static native <T> T runJavascriptFunctionImpl(JavaScriptObject o, String meth, JsArrayMixed args) /*-{
+    return (f = o && o[meth]) && @com.google.gwt.query.client.js.JsUtils::isFunction(*)(f) && f.apply(o, args) || null;
+  }-*/;
 
   /**
    * Check if a number is true in the javascript scope.
diff --git a/gwtquery-core/src/test/java/com/google/gwt/query/client/GQueryCoreTestGwt.java b/gwtquery-core/src/test/java/com/google/gwt/query/client/GQueryCoreTestGwt.java
index 1180f5cc..eb61169f 100644
--- a/gwtquery-core/src/test/java/com/google/gwt/query/client/GQueryCoreTestGwt.java
+++ b/gwtquery-core/src/test/java/com/google/gwt/query/client/GQueryCoreTestGwt.java
@@ -28,6 +28,7 @@ import java.util.List;
 import com.google.gwt.query.client.GQuery.Offset;
 import junit.framework.Assert;
 
+import com.google.gwt.dev.jjs.impl.AssertionNormalizer;
 import com.google.gwt.dom.client.Document;
 import com.google.gwt.dom.client.Element;
 import com.google.gwt.dom.client.InputElement;
@@ -1002,6 +1003,15 @@ public class GQueryCoreTestGwt extends GWTTestCase {
     assertFalse(JsUtils.truth(null));
     assertFalse(JsUtils.truth(""));
   }
+  
+  public void testUtilsCallFunc() {
+    Element e = JsUtils.runJavascriptFunction(document, "createElement", "div");
+    assertNotNull(e);
+    assertEquals(e.getTagName().toLowerCase(), "div");
+    
+    e = JsUtils.runJavascriptFunction(document, "foo", "bar", 2, true);
+    assertNull(e);
+  }
 
   public void testVal_issue98() {
     $(e).html(""