Question

您好我使用下面的代码在widget listview项目上加载图片。

Map<Integer, Boolean> flags = Collections.synchronizedMap(new HashMap<Integer, Boolean>());
    Bitmap mBitmap;
    Handler handler = new Handler(Looper.getMainLooper());


 flags.put(position, false);
            handler.post(new Runnable() {
                @Override
                public void run() {
                    ImageLoader imageLoader = ImageLoader.getInstance();
                    DisplayImageOptions options = new DisplayImageOptions.Builder().cacheInMemory(true)
                            .cacheOnDisc(true).resetViewBeforeLoading(true)
                            .build();
                    imageLoader.loadImage(item.mTooteet.getThumbUrl1() + "&userToken=" + userPreference.getUserToken(), options,
                            new SimpleImageLoadingListener() {
                                @Override
                                public void onLoadingStarted(String imageUri, View view) {
                                    Log.d(TAG,"onLoadingStarted  "+position);
                                }

                                @Override
                                public void onLoadingFailed(String imageUri, View view, FailReason failReason) {
                                    Log.d(TAG,"onLoadingFailed  "+position);
                                    flags.put(position, true);
                                }

                                @Override
                                public void onLoadingCancelled(String imageUri, View view) {
                                    Log.d(TAG,"onLoadingCancelled  "+position);
                                    flags.put(position, true);
                                }

                                @Override
                                public void onLoadingComplete(String arg0, View arg1, Bitmap bitmap) {
                                    Log.d(TAG,"onLoadingComplete  "+position);
                                    mBitmap = bitmap;
                                    flags.put(position, true);
                                }
                            });
                }
            });

            while (!flags.get(position)) {
                try {
                    Thread.sleep(100);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
            flags.put(position, false);
            if (mBitmap != null) {
                Log.d(TAG,"onLoadingComplete mBitmap not null "+position);
                remoteView.setImageViewBitmap(R.id.feed_image, mBitmap);
            } else {
                Log.d(TAG,"onLoadingComplete mBitmap null "+position);
                remoteView.setImageViewResource(R.id.feed_image, R.drawable.app_icon);
            }
            mBitmap = null;

在我的应用程序文件中，我使用了以下代码，

 // UNIVERSAL IMAGE LOADER SETUP
        DisplayImageOptions defaultOptions = new DisplayImageOptions.Builder()
                .cacheOnDisc(true).cacheInMemory(true)
                .imageScaleType(ImageScaleType.EXACTLY)
                .displayer(new FadeInBitmapDisplayer(300)).build();

        ImageLoaderConfiguration uilConfig = new ImageLoaderConfiguration.Builder(
                getApplicationContext())
                .defaultDisplayImageOptions(defaultOptions)
                .memoryCache(new WeakMemoryCache())
                .discCacheSize(100 * 1024 * 1024).build();

        ImageLoader.getInstance().init(uilConfig);
        // END - UNIVERSAL IMAGE LOADER SETUP

但是这段代码每次都会从url下载图片。每次滚动我的应用程序小部件列表视图时，我都不想重新加载它。首次下载后应将其保留在缓存中。你能建议我这么做吗？

Answer 1

从您的代码中，您每次都在创建DisplayImageOptions。我认为这是制作DisplayImageOptions一次的原因（在你的Runnable对象之外）使用方式如下：

ImageLoader imageLoader = ImageLoader.getInstance();
DisplayImageOptions options = new DisplayImageOptions.Builder().cacheInMemory(true)
                        .cacheOnDisc(true).resetViewBeforeLoading(true)
                        .build()

然后在runnable中运行其他代码

   handler.post(new Runnable() {
            @Override
            public void run() {
                 imageLoader.loadImage(..........)///same code you written

}

}）;

请让我知道结果。

如何在Universal Image Loader android

1 个答案: