心有猛虎，细嗅蔷薇: ADF_229：ADF Mobile 11.1.2.4 Samples 介绍（15）：Weather3

2013年5月22日星期三

ADF_229：ADF Mobile 11.1.2.4 Samples 介绍（15）：Weather3

开发运行环境：JDeveloper 11.1.2.4 + Android SDK r21.1

Weather3与Weather2基本实现相同，除了点击查询按钮时，实现了异步调用。

知识点：

1. 新增ForecastWorker.java，作为多线程任务类

package mobile;

import oracle.adfmf.framework.api.AdfmfJavaUtilities;

public class ForecastWorker implements Runnable {
CityInformation ci = null;
String zip = "";

public ForecastWorker() {
super();
}

public ForecastWorker(CityInformation ci, String zip) {
this.ci = ci;
this.zip = zip;
}

public void run() {
ci.retrieveForecastAsync(zip);
AdfmfJavaUtilities.flushDataChangeEvent();
}
}

注意这行代码：AdfmfJavaUtilities.flushDataChangeEvent();，有了这行代码，界面才能刷新。

2. CityInformation.java中的相关方法

public synchronized boolean retrieveForecast(String zip) {
// First lets clear the cityForecast
cityForecast.setSuccess((Boolean)Boolean.FALSE);
cityForecast.setResponseText((String)"Running...");
cityForecast.setCity((String)"");
cityForecast.setState((String)"");
cityForecast.setWeatherStationCity((String)"");
cityForecast.clearForecast();

ForecastWorker fw = new ForecastWorker(this, zip);
Thread t = new Thread(fw);
t.start();

return true;
}

public synchronized boolean retrieveForecastAsync(String zip) {
// Before we get any forecast, we get the WeatherInfo if it's not retrieved yet
weatherInfo.retreiveWeatherInfo();

boolean ret = false;

List pnames = new ArrayList();
List params = new ArrayList();
List ptypes = new ArrayList();

pnames.add("ZIP");
ptypes.add(String.class);
params.add(zip);

try {
// This calls the DC method and gives us the Return
GenericType result =
(GenericType)AdfmfJavaUtilities.invokeDataControlMethod("WeatherDC", null, "GetCityForecastByZIP",
pnames, params, ptypes);

// This will give us the CityForeCast object from the result
GenericType cfgt = (GenericType)result.getAttribute(0);

// Read the attributes from the GenericType returend from the getCityForecastByZip call
cityForecast.setSuccess((Boolean)cfgt.getAttribute("Success"));
cityForecast.setResponseText((String)cfgt.getAttribute("ResponseText"));
cityForecast.setCity((String)cfgt.getAttribute("City"));
cityForecast.setState((String)cfgt.getAttribute("State"));
cityForecast.setWeatherStationCity((String)cfgt.getAttribute("WeatherStationCity"));

// This will give us the ForecastResult which is a collection of Forecast objects
GenericType frgt = (GenericType)cfgt.getAttribute("ForecastResult");

// fcgt is a collection of Forecast objects, get all those in a loop
int count = frgt.getAttributeCount();
for (int i = 0; i < count; i++) {
// Get each individual WeatherDescription object
GenericType fgt = (GenericType)frgt.getAttribute(i);

// Now make a real WeatherDescription java object out of this GenericType
Forecast f = (Forecast)GenericTypeBeanSerializationHelper.fromGenericType(Forecast.class, fgt);
f.weatherInfo = weatherInfo;

// Now get the Temperature subobject
GenericType tempgt = (GenericType)fgt.getAttribute("Temperatures");

// Now set the high and low temps
f.setDaytimeHigh((String)tempgt.getAttribute(0));
f.setMorningLow((String)tempgt.getAttribute(1));
// Now add this to our holder of all WeatherDescriptions
cityForecast.addForecast(f);

}
ret = true;
} catch (AdfInvocationException e) {
Trace.log(Utility.ApplicationLogger, Level.SEVERE, CityInformation.class, "retrieveForecastAsync",
">>>>>> AdfInvocationException=" + e.getMessage());
AdfException ex = new AdfException("Error Invoking Web Service. Please try later", AdfException.WARNING);
throw ex;

} catch (Exception e2) {
Trace.log(Utility.ApplicationLogger, Level.SEVERE, CityInformation.class, "retrieveForecastAsync",
">>>>>> Exception=" + e2.getMessage());
AdfException ex = new AdfException("Error Invoking Web Service. Please try later", AdfException.WARNING);
throw ex;
}
return ret;
}

3. 部署，运行
（1）可以看到点击查询按钮后，会马上进入到下一个页面，但是数据并没有完全得到。
这时，并不会Block用户可以做其他事情。