NSDocument 打开默认文档

NSDocument opening over a default document

我正在 Swift 中编写 NSDocument-based 应用程序。如果应用程序未使用文档参数启动,我将其设置为打开默认文档。

我注意到如果我启动应用程序然后立即打开另一个文档,比如使用“打开”或“最近”,“无标题”默认文档会保留,即使它没有被触及。

我的印象是,在此工作流程中,无标题文档被视为 "accidental" 并且应该被删除。这样对吗?如果是这样,我应该手动删除此 window,还是我忽略了某个设置?

您描述的行为不是自动的。有关如何处理这种情况的示例,请参阅 open-source TextEdit 示例代码。具体来说,take a look-[DocumentController replaceTransientDocument:] 实施。

- (void)replaceTransientDocument:(NSArray *)documents {
    // Transient document must be replaced on the main thread, since it may undergo automatic display on the main thread.
    if ([NSThread isMainThread]) {
        NSDocument *transientDoc = [documents objectAtIndex:0], *doc = [documents objectAtIndex:1];
        NSArray *controllersToTransfer = [[transientDoc windowControllers] copy];
        NSEnumerator *controllerEnum = [controllersToTransfer objectEnumerator];
        NSWindowController *controller;

        [controllersToTransfer makeObjectsPerformSelector:@selector(retain)];

        while (controller = [controllerEnum nextObject]) {
            [doc addWindowController:controller];
            [transientDoc removeWindowController:controller];
        }
        [transientDoc close];

        [controllersToTransfer makeObjectsPerformSelector:@selector(release)];
        [controllersToTransfer release];

    // We replaced the value of the transient document with opened document, need to notify accessibility clients.
    for (NSLayoutManager *layoutManager in [[(Document *)doc textStorage] layoutManagers]) {
        for (NSTextContainer *textContainer in [layoutManager textContainers]) {
        NSTextView *textView = [textContainer textView];
        if (textView) NSAccessibilityPostNotification(textView, NSAccessibilityValueChangedNotification);
        }
    }

    } else {
        [self performSelectorOnMainThread:_cmd withObject:documents waitUntilDone:YES];
    }
}

如果您还查看 -openDocumentWithContentsOfURL:display:error: 和其他一些调用上述方法的地方,您将很好地了解它们如何替换 "transient document"("Untitled" 文档)与打开的文档。

希望对您有所帮助。