传递使用param的android函数

Question

我一直在使用Callable,但现在我需要在该call方法中使用param的函数.我知道这不是一种能力,call我怎么能这样做？

我目前有什么(错误的):

AsyncTask async = new MyAsyncTask();
async.finished(new Callable(param) {
    // the function called during async.onPostExecute;
    doSomething(param);
});
async.execute(url);

MyAsyncTask:

...
@Override
protected void onPostExecute(JSONObject result)  {
    //super.onPostExecute(result);
    if(result != null) {
        try {
            this._finished.call(result); // not valid because call accepts no params
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
}

public void finished(Callable<Void> func) {
    this._finished = func;
}
...

Answer 1

如果你创建param了一个最终变量,你可以从以下内容中引用它Callable:

final String param = ...;
async.finished(new Callable() {
    // the function called during async.onPostExecute;
    doSomething(param);
});

你创建的时候必须这样做Callable- 你以后不能给它值.如果由于某种原因需要它,你必须基本上使用共享状态 - 一些Callable有权访问的"持有者" ,并且可以在Callable执行之前将值设置到其中.这可能就是它MyAsyncTask本身:

final MyAsyncTask async = new MyAsyncTask();
async.finished(new Callable() {
    // the function called during async.onPostExecute;
    doSomething(async.getResult());
});
async.execute(url);

然后:

private JSONObject result;
public JSONObject getResult() {
    return result;
}

@Override
protected void onPostExecute(JSONObject result)  {
    this.result = result;
    if(result != null) {
        try {
            this._finished.call();
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
}