SWT异常: org.eclipse.swt.SWTException: Invalid thread access

最近在学习swt的东西，遇到一个问题，特转录如下。

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SWT异常: org.eclipse.swt.SWTException: Invalid thread access

在创建SWT界面的线程之外的线程中尝试去修改界面元素.将抛出以下异常

Exception in thread "Thread-0" org.eclipse.swt.SWTException: Invalid thread access
    at org.eclipse.swt.SWT.error(SWT.java:2942)
    at org.eclipse.swt.SWT.error(SWT.java:2865)
    at org.eclipse.swt.SWT.error(SWT.java:2836)

上述Thread-0是另外开启的一个线程.

【解析】:
在SWT程序中,
SWT会自动创建一个用户界面线程
非用户界面线程不能直接操作用户界面线程
要想在另外一个线程中尝试修改用户界面,应采用一下方法:

if (!this.display.isDisposed()) ...{
    Runnable runnable = new Runnable() ...{
        public void run() ...{
            // 你改界面的代码
        }
    };
    display.syncExec(runnable); // 关键在这一句上（同步调用，等待主界面线程处理完成之后）
}

swt-doc中的说明:

public void syncExec(java.lang.Runnable runnable)Causes the run() method of the runnable to be invoked by the user-interface thread at the next reasonable opportunity. The thread which calls this method is suspended until the runnable completes.
Parameters:
runnable - code to run on the user-interface thread. (同步调用,需要等待主界面处理完成之后，才能继续)
此外,与之对应的另一个方法:

public void asyncExec(java.lang.Runnable runnable)Causes the run() method of the runnable to be invoked by the user-interface thread at the next reasonable opportunity. The caller of this method continues to run in parallel, and is not notified when the runnable has completed.
Parameters:
runnable - code to run on the user-interface thread. (异步调用,不等待主界面线程处理结果)