安卓獲取當前的Activity即CurrentActivity有兩種方法：

1.

在BaseActivity中 宣告一個 ：private static volatile Activity mCurrentActivity;

public static Activity getCurrentActivity() {
    return mCurrentActivity;
}

private void setCurrentActivity(Activity activity) {
    mCurrentActivity = activity;
}

在BaseActivity中的OnResume（）方法中：

setCurrentActivity(this);

這樣在外圍直接獲取就可以：

Activity currentActivity = BaseActivity.getCurrentActivity();

如果想判斷比如：MainActivity是不是CurrentActivity 使用方法：

BaseActivity.getCurrentActivity() instanceof MainActivity 使用 instanceof 進行判斷

第二種方法：

在CCApplication中定義一個：

private volatile Activity mCurrentActivity;並且新增get set方法

public synchronized Activity getCurrentActivity() {
    return mCurrentActivity;
}

public synchronized void setCurrentActivity(Activity activity) {
    mCurrentActivity = activity;
}

然後宣告一個類：

private class CCActivityLifecycleCallbacks implements ActivityLifecycleCallbacks {

    @Override
    public void onActivityCreated(Activity activity, Bundle savedInstanceState) {
    }

    @Override
    public void onActivityStarted(Activity activity) {
        MonkeyLog.d(TAG, "onActivityStarted :" + activity);
    }

    @Override
    public void onActivityResumed(Activity activity) {
        mIsInForeground = true;
        Adjust.onResume();
        setCurrentActivity(activity);
    }

    @Override
    public void onActivityPaused(Activity activity) {
        mIsInForeground = false;
        Adjust.onPause();
        setCurrentActivity(null);
    }

    @Override
    public void onActivityStopped(Activity activity) {

    }

    @Override
    public void onActivitySaveInstanceState(Activity activity, Bundle outState) {

    }

    @Override
    public void onActivityDestroyed(Activity activity) {

    }
}

在CCApplication的 onCreate()方法中呼叫：

registerActivityLifecycleCallbacks(new CCActivityLifecycleCallbacks());

在外圍用的時候直接呼叫Get方法即可:

ActivityUtil.runOnUiThread(new Runnable() {
    @Override
    public void run() {
        Activity currentActivity = CCApplication.getInstance().getCurrentActivity();
       if (currentActivity != null) {
           // TODO: 2018/8/15  
       }

    }
});

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