使用SnackBar实例再次显示

看到源代码,我可以看到“取消snackbar”将使当前的SnackBars无效。

源代码-SnackBar

public void dismiss(Callback callback, int event) {
    synchronized (mLock) {
        if (isCurrentSnackbarLocked(callback)) {
            cancelSnackbarLocked(mCurrentSnackbar, event);
        } else if (isNextSnackbarLocked(callback)) {
            cancelSnackbarLocked(mNextSnackbar, event);
        }
    }
}

/**
 * Should be called when a Snackbar is no longer displayed. This is after any exit
 * animation has finished.
 */
public void onDismissed(Callback callback) {
    synchronized (mLock) {
        if (isCurrentSnackbarLocked(callback)) {
            // If the callback is from a Snackbar currently show, remove it and show a new one
            mCurrentSnackbar = null;
            if (mNextSnackbar != null) {
                showNextSnackbarLocked();
            }
        }
    }
}

因此,当您在同一实例上进行显示时,此代码将运行

public void show(int duration, Callback callback) {
    synchronized (mLock) {
        if (isCurrentSnackbarLocked(callback)) {
            // Means that the callback is already in the queue. We'll just update the duration
            mCurrentSnackbar.duration = duration;

            // If this is the Snackbar currently being shown, call re-schedule it's
            // timeout
            mHandler.removeCallbacksAndMessages(mCurrentSnackbar);
            scheduleTimeoutLocked(mCurrentSnackbar);
            return;
        } else if (isNextSnackbarLocked(callback)) {
            // We'll just update the duration
            mNextSnackbar.duration = duration;
        } else {
            // Else, we need to create a new record and queue it
            mNextSnackbar = new SnackbarRecord(duration, callback);
        }

        if (mCurrentSnackbar != null && cancelSnackbarLocked(mCurrentSnackbar,
                Snackbar.Callback.DISMISS_EVENT_CONSECUTIVE)) {
            // If we currently have a Snackbar, try and cancel it and wait in line
            return;
        } else {
            // Clear out the current snackbar
            mCurrentSnackbar = null;
            // Otherwise, just show it now
            showNextSnackbarLocked();
        }
    }
}

如果snackbar为空,则不会显示snackbar。

解决方案

您不应该在SnackBar上调用discose,当持续时间到期或单击操作按钮时,它会自动隐藏。只需再次调用show方法,而不必首先调用discuss,即可再次显示SnackBar。