带有外部源的贴纸扩展答案

【问题标题】：Sticker extension with external source带有外部源的贴纸扩展
【发布时间】：2017-01-24 09:21:15
【问题描述】：

我想在我现有的应用程序中添加一个 iMessage 扩展程序以提供自定义贴纸。首先我做了：

Xcode > 文件 > 添加目标 > IMessage 扩展

然后，我找到了一些可以用作测试贴纸的图片网址。

我的控制器看起来像这样：

import UIKit
import Messages

class MessagesViewController: MSMessagesAppViewController, MSStickerBrowserViewDataSource {

    var stickers = [MSSticker]();
    var url = ["http://iconizer.net/files/Brightmix/orig/monotone_close_exit_delete_small.png","https://upload.wikimedia.org/wikipedia/commons/d/d5/Japan_small_icon.png"];

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view.

        print(" ----- HERE");

        loadStickers();
        createStickerBrowser();
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

    // MARK: - Stickers Handling

    func loadStickers() {

        print(" ----- loadStickers");

        for i in 0...1 {
            do {
                let sticker = try MSSticker(contentsOfFileURL: URL(string: url[i])!, localizedDescription: "\(i)")
                print(" \(i) : \(sticker)");
                stickers.append(sticker)
            } catch {
                print("error \(error)");
            }
        }
    }

    func createStickerBrowser() {

        print(" ----- createStickerBrowser");

        let controller = MSStickerBrowserViewController(stickerSize: .large)

        addChildViewController(controller)
        view.addSubview(controller.view)

        controller.stickerBrowserView.backgroundColor = UIColor.gray
        controller.stickerBrowserView.dataSource = self;

        view.topAnchor.constraint(equalTo: controller.view.topAnchor).isActive = true
        view.bottomAnchor.constraint(equalTo: controller.view.bottomAnchor).isActive = true
        view.leftAnchor.constraint(equalTo: controller.view.leftAnchor).isActive = true
        view.rightAnchor.constraint(equalTo: controller.view.rightAnchor).isActive = true
    }

    // MARK: - MSStickerBrowserViewDataSource

    func numberOfStickers(in stickerBrowserView: MSStickerBrowserView) -> Int {
        return stickers.count
    }

    func stickerBrowserView(_ stickerBrowserView: MSStickerBrowserView, stickerAt index: Int) -> MSSticker {
        return stickers[index]
    }

    // MARK: - Conversation Handling

    override func willBecomeActive(with conversation: MSConversation) {
        // Called when the extension is about to move from the inactive to active state.
        // This will happen when the extension is about to present UI.

        // Use this method to configure the extension and restore previously stored state.
        print("----- willBecomeActive");
    }

    override func didResignActive(with conversation: MSConversation) {
        // Called when the extension is about to move from the active to inactive state.
        // This will happen when the user dissmises the extension, changes to a different
        // conversation or quits Messages.

        // Use this method to release shared resources, save user data, invalidate timers,
        // and store enough state information to restore your extension to its current state
        // in case it is terminated later.
        print("----- didResignActive");
    }

    override func didReceive(_ message: MSMessage, conversation: MSConversation) {
        // Called when a message arrives that was generated by another instance of this
        // extension on a remote device.

        // Use this method to trigger UI updates in response to the message.
    }

    override func didStartSending(_ message: MSMessage, conversation: MSConversation) {
        // Called when the user taps the send button.
    }

    override func didCancelSending(_ message: MSMessage, conversation: MSConversation) {
        // Called when the user deletes the message without sending it.

        // Use this to clean up state related to the deleted message.
    }

    override func willTransition(to presentationStyle: MSMessagesAppPresentationStyle) {
        // Called before the extension transitions to a new presentation style.

        // Use this method to prepare for the change in presentation style.
    }

    override func didTransition(to presentationStyle: MSMessagesAppPresentationStyle) {
        // Called after the extension transitions to a new presentation style.

        // Use this method to finalize any behaviors associated with the change in presentation style.
    }

}

我没有看到我的任何印刷品，背景颜色还可以，但我看不到我的贴纸。苹果文档这样说：

fileURL 此标签显示的图像的 URL。此网址必须参考保存在设备上的文件。文件必须是 PNG、APNG、 GIF 或 JPEG，并且必须小于 500 KB。为了获得最佳结果，图像不应小于 100 x 100 点或大于 206 x 206 分。始终提供@3x 图像（300 x 300 像素到 618 x 618 像素）。系统通过降尺度生成@2x 和@1x 版本运行时的@3x 图像。

那么你知道一种保存从服务器下载的图片到本地的方法吗？

【问题讨论】：

标签： ios swift ios10 imessage

【解决方案1】：

只需使用扩展名（png 或 jpg）保存下载的图像。在我的示例中，我将 png 文件保存在可丢弃缓存文件（库/缓存）的位置

[...]/Library/Caches/StickerCache/Pack_1188767/image_166176391.png

【讨论】：

【解决方案2】：

您可以轻松地将普通和动画贴纸添加到现有应用中。

添加新目标并选择“贴纸应用扩展”。不幸的是，您必须滚动才能看到此选项。 ?

“iMessage 扩展”是正确的选择，如果您想要的不仅仅是贴纸，例如交互式 iMessage 应用程序。

【讨论】：