GWT JSNI -如何使用jsni从java代码调用外部javascript

Question

我想在我的gwt应用程序中调用外部javascript函数。

当我使用这段代码时，它工作得很好:我已经导入了javaScript，我可以在客户端的firebug中看到它。

public static native void showOfflineMap(String pRegionId, String pMapServerHost, String pMapServerPath, String pMapTileLayers, String pFoiLayers,
            double pMapCenterLon, double pMapCenterLat, int pInitZoom, String pNavPanel, boolean pCustJsFunction, int pMapWidth, int pMapHeight,
            String pAdditional) /*-{
                                alert("ff");
                                                $wnd.createPluginMap(
                                                pRegionId,
                                                pMapServerHost,
                                                pMapServerPath,
                                                pMapTileLayers,
                                                pFoiLayers,
                                                pMapCenterLon,
                                                pMapCenterLat,
                                                pInitZoom,
                                                pNavPanel,
                                                pCustJsFunction,
                                                pMapWidth,
                                                pMapHeight,
                                                pAdditional
                                                )


                                                }-*/;

但当我想起

alert("ff");

它抛出此异常：

Sun Jul 06 16:36:49 GMT+03:30 2014 com.google.gwt.logging.client.LogConfiguration
SEVERE: (TypeError) @ir.dena.avl.client.offlinemap.MapUtil::showOfflineMap(Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;DDILjava/lang/String;ZIILjava/lang/String;)([string: 'offline_map', string: 'http://192.168.10.196:7001', string: '/mapviewer', string: 'mp.LINE_TILE', string: 'NONE', double: 56.0046, double: 32.629365, int: 3, string: 'WEST', bool: false, int: 1000, int: 800, string: 'OVER:MARQUEE:DISTANCE:REDLINE:FOISELECT']): $wnd.createPluginMap is not a functioncom.google.gwt.core.client.JavaScriptException: (TypeError) @ir.dena.avl.client.offlinemap.MapUtil::showOfflineMap(Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;DDILjava/lang/String;ZIILjava/lang/String;)([string: 'offline_map', string: 'http://192.168.10.196:7001', string: '/mapviewer', string: 'mp.LINE_TILE', string: 'NONE', double: 56.0046, double: 32.629365, int: 3, string: 'WEST', bool: false, int: 1000, int: 800, string: 'OVER:MARQUEE:DISTANCE:REDLINE:FOISELECT']): $wnd.createPluginMap is not a function
    at com.google.gwt.dev.shell.BrowserChannelServer.invokeJavascript(BrowserChannelServer.java:249)
    at com.google.gwt.dev.shell.ModuleSpaceOOPHM.doInvoke(ModuleSpaceOOPHM.java:136)
    at com.google.gwt.dev.shell.ModuleSpace.invokeNative(ModuleSpace.java:576)
    at com.google.gwt.dev.shell.ModuleSpace.invokeNativeVoid(ModuleSpace.java:304)
    at com.google.gwt.dev.shell.JavaScriptHost.invokeNativeVoid(JavaScriptHost.java:107)
    at ir.dena.avl.client.offlinemap.MapUtil$.showOfflineMap(MapUtil.java)
    at ir.dena.avl.client.offlinemap.OfflineMapView.createMainPanel(OfflineMapView.java:31)
    at ir.jalal.core.client.view.BaseView.<init>(BaseView.java:71)
    at ir.dena.avl.client.offlinemap.OfflineMapView.<init>(OfflineMapView.java:20)
    at ir.dena.avl.client.ViewFactory$32.onSuccess(ViewFactory.java:354)
    at com.google.gwt.core.client.GWT$1.execute(GWT.java:286)
    at com.google.gwt.core.client.impl.SchedulerImpl$Task$.executeScheduled$(SchedulerImpl.java:50)
    at com.google.gwt.core.client.impl.SchedulerImpl.runScheduledTasks(SchedulerImpl.java:180)
    at com.google.gwt.core.client.impl.SchedulerImpl.flushPostEventPumpCommands(SchedulerImpl.java:345)
    at com.google.gwt.core.client.impl.SchedulerImpl$Flusher.execute(SchedulerImpl.java:78)
    at com.google.gwt.core.client.impl.SchedulerImpl.execute(SchedulerImpl.java:138)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at com.google.gwt.dev.shell.MethodAdaptor.invoke(MethodAdaptor.java:103)
    at com.google.gwt.dev.shell.MethodDispatch.invoke(MethodDispatch.java:71)
    at com.google.gwt.dev.shell.OophmSessionHandler.invoke(OophmSessionHandler.java:172)
    at com.google.gwt.dev.shell.BrowserChannelServer.reactToMessagesWhileWaitingForReturn(BrowserChannelServer.java:338)
    at com.google.gwt.dev.shell.BrowserChannelServer.invokeJavascript(BrowserChannelServer.java:219)
    at com.google.gwt.dev.shell.ModuleSpaceOOPHM.doInvoke(ModuleSpaceOOPHM.java:136)
    at com.google.gwt.dev.shell.ModuleSpace.invokeNative(ModuleSpace.java:576)
    at com.google.gwt.dev.shell.ModuleSpace.invokeNativeObject(ModuleSpace.java:284)
    at com.google.gwt.dev.shell.JavaScriptHost.invokeNativeObject(JavaScriptHost.java:91)
    at com.google.gwt.core.client.impl.Impl.apply(Impl.java)
    at com.google.gwt.core.client.impl.Impl.entry0(Impl.java:356)
    at sun.reflect.GeneratedMethodAccessor88.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at com.google.gwt.dev.shell.MethodAdaptor.invoke(MethodAdaptor.java:103)
    at com.google.gwt.dev.shell.MethodDispatch.invoke(MethodDispatch.java:71)
    at com.google.gwt.dev.shell.OophmSessionHandler.invoke(OophmSessionHandler.java:172)
    at com.google.gwt.dev.shell.BrowserChannelServer.reactToMessages(BrowserChannelServer.java:293)
    at com.google.gwt.dev.shell.BrowserChannelServer.processConnection(BrowserChannelServer.java:547)
    at com.google.gwt.dev.shell.BrowserChannelServer.run(BrowserChannelServer.java:364)
    at java.lang.Thread.run(Unknown Source)

请帮帮我,

提前感谢

Answer 1

确保在createPluginMap函数之前将脚本链接到 .nocache.js之前，而不是异步链接它(我的意思是应该没有<script defer或<script async)

Answer 2

我假设这是一个竞赛条件，当您期望它存在时，函数createPluginMap就不存在了。

试着替换

alert("ff");

使用

alert(''+!!$wnd.createPluginMap);

如果你在警报中出现“假”，这就是原因。如果是真的，我会设法想出一个不同的答案;)