如何在开发 Harmony 应用程序时将图像作为图标添加到选项卡内？

Question

我想在选项卡中添加图片，我有图片资源 ID，但 tab.setIconElement(Element) 需要元素。
目前，我正在尝试这样

tabList = (TabList) findComponentById(ResourceTable.Id_TabList);
TabList.Tab tab = tabList.new Tab(this);
tab.setIconElement(Element); // want the image as an element
tabList.addTab(tab);

如何在选项卡中添加图像或仅使用图像资源 ID 创建其元素？或者还有其他方法吗？

Answer 1

首先，您必须使用 ImageSource.DecodingOptions 解码图像资源，然后从 PixelMap 创建 PixelMapElement 。最后使用 set PixelMapElement to Tab using setIconElement API,

    public static void createIcons(AbilitySlice abilitySlice, TabList.Tab tab, int id) {
        if (tab == null) {
            LogUtil.error(TAG, "createTabIcon failed");
            return;
        }
        try {
            PixelMap pixelMap = createByResourceId(abilitySlice, id, "image/png");
            PixelMapElement pixelMapElement = new PixelMapElement(pixelMap);
            pixelMapElement.setBounds(0, 0, 70, 70);
            tab.setIconElement(pixelMapElement);
            tab.setPadding(5, 5, 5, 5);
        } catch (NotExistException | IOException e) {
            LogUtil.error(TAG, "createTabIcon " + e.getLocalizedMessage());
        }
    }

    
    public static PixelMap createByResourceId(AbilitySlice abilitySlice, int id, String str)
            throws IOException, NotExistException {
        if (abilitySlice == null) {
            LogUtil.error(TAG, "createByResourceId but slice is null");
            throw new IOException();
        } else {
            ResourceManager resourceManager = abilitySlice.getResourceManager();
            if (resourceManager != null) {
                Resource resource = resourceManager.getResource(id);
                if (resource != null) {
                    ImageSource.SourceOptions sourceOptions = new ImageSource.SourceOptions();
                    sourceOptions.formatHint = str;
                    ImageSource create = ImageSource.create(readResource(resource), sourceOptions);
                    resource.close();
                    if (create != null) {
                        ImageSource.DecodingOptions decodingOptions = new ImageSource.DecodingOptions();
                        decodingOptions.desiredSize = new Size(0, 0);
                        decodingOptions.desiredRegion = new ohos.media.image.common.Rect(0, 0, 0, 0);
                        decodingOptions.desiredPixelFormat = PixelFormat.ARGB_8888;
                        PixelMap pixelMap = create.createPixelmap(decodingOptions);
                        return pixelMap;
                    }
                    LogUtil.error(TAG, "imageSource is null");
                    throw new FileNotFoundException();
                }
                LogUtil.error(TAG, "get resource failed");
                throw new IOException();
            }
            LogUtil.error(TAG, "get resource manager failed");
            throw new IOException();
        }
    }

    private static byte[] readResource(Resource resource) throws IOException {
        ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
        byte[] bArr = new byte[1024];
        while (true) {
            try {
                int read = resource.read(bArr, 0, 1024);
                if (read == -1) {
                    break;
                }
                byteArrayOutputStream.write(bArr, 0, read);
            } catch (IOException e) {
                LogUtil.error(TAG, "readResource failed " + e.getLocalizedMessage());
            }finally {
                byteArrayOutputStream.close();
            }
        }
        LogUtil.debug(TAG, "readResource finish");
        LogUtil.debug(TAG, "readResource len: " + byteArrayOutputStream.size());
        return byteArrayOutputStream.toByteArray();
    }

如何在开发 Harmony 应用程序时将图像作为图标添加到选项卡内？

How to add image inside a tab as a icon while developing Harmony application?

java

android

huawei-mobile-services

huawei-developers

harmonyos