java - 如何将消息发送到静态处理程序？

Question

我不得不声明一个静态处理程序，因为一些 Java 废话和泄漏。

static class ParsingCompleteHandler extends Handler {
    private final WeakReference<BackupActivity> mTargetActivity;
    ParsingCompleteHandler(BackupActivity targetActivity) {
        mTargetActivity = new WeakReference<BackupActivity>(targetActivity);
    }

    @Override
    public void handleMessage(Message msg) {
        BackupActivity targetActivity = mTargetActivity.get();
        targetActivity.updateDialog();
    }
};  

在代码的其他地方(在可运行的内部)我试图将 sendEmptyMessage() 发送给这个处理程序

    Runnable runnable = new Runnable() {
        @Override
        public void run() {
            lastBackupDataObject = getBackupDataObjectFromFile(file);   
            parsingCompleteHandler.sendEmptyMessage(0);
        }
    };
    Thread parsingThread = new Thread(runnable);
    parsingThread.start();

但由于 sendEmptyMessage() 方法不是静态的(现在的处理程序是静态的)，显然我不能这样做。我需要向处理程序发送一条消息，因为这就是它的用途。我该怎么做？

Answer 1

您可以通过将您的处理程序对象作为类全局对象来执行此操作，而不是调用此消息，这应该可以工作

eg.

public class SomeClass{

ParsingCompleteHandler  parsingCompleteHandler;


static class ParsingCompleteHandler extends Handler {
    private final WeakReference<BackupActivity> mTargetActivity;
    ParsingCompleteHandler(BackupActivity targetActivity) {
        mTargetActivity = new WeakReference<BackupActivity>(targetActivity);
    }

    @Override
    public void handleMessage(Message msg) {
        BackupActivity targetActivity = mTargetActivity.get();
        targetActivity.updateDialog();
    }
}; 

比做

    Runnable runnable = new Runnable() {
        @Override
        public void run() {
            lastBackupDataObject = getBackupDataObjectFromFile(file);   
            parsingCompleteHandler.sendEmptyMessage(0);
        }
    };
    Thread parsingThread = new Thread(runnable);
    parsingThread.start();