间隔一段时间后从Arraylist获取并定期更新Imageview

时间:2019-06-24 09:23:41

标签: android arraylist imageview

我准备好一个arraylist(字符串),其中包含一些图像的Web链接。现在,我想在一段时间间隔(例如4秒)后使用Glide使用图像链接定期更新imageview。 在使用新图像更新imageview之前,设置暂停时遇到了问题。

我的代码:

//i is the count initially set to 0. StringLink is the arraylist 
//StatusImage is the imageview


//first I set the first link from StringLink to StatusImage

Glide.with(ShowStatusPostActivity.this).setDefaultRequestOptions(placeholderRequest).load(StringLink.get(i)).into(StatusImage);



//next I try to set the next links from StringLink to StatusImage
//I try to keep one image for 4 seconds and then change it. Here I use Handler to do so

 for(; i< StringLink.size();i++ )
        {


            try{


                new Handler().postDelayed(new Runnable() {
                    @Override
                    public void run() {
                        StatusImage.post(new Runnable() {
                            @Override
                            public void run() {

                                Glide.with(ShowStatusPostActivity.this).setDefaultRequestOptions(placeholderRequest).load(StringLink.get(i))
                                        .listener(new RequestListener<Drawable>() {
                                            @Override
                                            public boolean onLoadFailed(@Nullable GlideException e, Object model, Target<Drawable> target, boolean isFirstResource) {
                                                return false;
                                            }

                                            @Override
                                            public boolean onResourceReady(Drawable resource, Object model, Target<Drawable> target, DataSource dataSource, boolean isFirstResource) {



                                                return false;
                                            }
                                        })
                                        .into(StatusImage);



                            }
                        });
                    }
                }, 4000);


            }
            catch (Exception e){}




        }

但是我在第二个Glide中遇到了ArrayIndexOutofBound的错误。

我不认为在for循环内使用Handler是使周期性成为一个很好的主意,我也尝试了Thread.sleep但它也没有起作用。

在这里我能做些什么吗?

1 个答案:

答案 0 :(得分:2)

我希望以下功能会有所帮助。每隔4秒钟将触发一次,并显示吐司消息。您可以调用函数以基于I计数器加载图像。

int i = 0;
int length = 5;
private Handler mHandler;
private Runnable mRunnable;  

public void startPeriodicFunciton() {

    mHandler = new Handler();
    mRunnable = new Runnable() {
        @Override
        public void run() {
            // Do some task on delay
            //   doTask();

            // You can add your fuction to load image here
            i++;
            if (i == length)
                i = 0;
            Toast.makeText(MainActivity.this, "value : " + i, 
Toast.LENGTH_SHORT).show();
            mHandler.postDelayed(mRunnable, 4000);

        }
    };
    mHandler.postDelayed(mRunnable, (4000));
}