Question

我正在尝试为Android编写一个简单的应用程序。我正在尝试加载7个jpg图像。如何在每个图像视图中加载图像时显示动画循环进度条。我使用两个进度条来执行此操作。我已尝试下面给出的代码。

            if (mainImageURl.startsWith("http://")) {
                //resultp   =   arraylist.get(0);
                //Picasso.with(getActivity()).load(mainImageURl).into(mainImageView);
            //imageLoader.DisplayImage((mainImageURl), mainImageView);
            Picasso.with(getActivity())
            .load(mainImageURl)
           .into(mainImageViewnew Callback() {

                    @Override
                    public void onSuccess() {
                        // TODO Auto-generated method stub
                        progress1.setVisibility(View.GONE);
                    }

                    @Override
                    public void onError() {
                        // TODO Auto-generated method stub

                    }
                });

            }
            else if (stage1ImageURL.startsWith("http://")) {
                //resultp   =   arraylist.get(0);
                //Picasso.with(getActivity()).load(mainImageURl).into(mainImageView);
            //imageLoader.DisplayImage((mainImageURl), mainImageView);
            Picasso.with(getActivity())
            .load(mainImageURl)
            .into(mainImageViewCallback() {

                    @Override
                    public void onSuccess() {
                        // TODO Auto-generated method stub
                        progress2.setVisibility(View.GONE);
                    }

                    @Override
                    public void onError() {
                        // TODO Auto-generated method stub

                    }
                });

            }

Answer 1

我创建了一个asynctask＆＃34; ImageLoading＆＃34;。这将加载＆＃34; loadingimg＆＃34; gif on pre方法..并尝试从web-service（在php中构建）获取背景方法上的图像。当图像背景返回时，它将使加载gif不可见，并在返回true时加载图像。

确保启动xampp服务器（apache以及mysql）

xampp-＆GT; MySQL的

xampp-＆gt; [内部htdocs-＆gt; imgloading文件夹]

＆＃34; showLoading.php＆＃34;

<?php
$id=$_GET["id"];

$con=mysqli_connect("localhost","root","","imgloading");
$query_result=mysqli_query($con,"select img from img where id=1");
//since id=1 contain the loading gif image...which shows until original image loaded
while($row=mysqli_fetch_row($query_result))
{
   $img=$row[0];
}
echo '<img src="data:image/*;base64,'.base64_encode($img).'" width="32" heigth="32"/>';?>

＆＃34; getImage.php＆＃34;

<?php
$id=$_GET["id"];

$con=mysqli_connect("localhost","root","","imgloading");
$query_result=mysqli_query($con,"select img from img where id=".$id);
while($row=mysqli_fetch_row($query_result))
{
   $img=$row[0];
}
echo $img;
?>

MainActivity.java

公共类MainActivity扩展了ActionBarActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) 
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        loadingImg=(WebView)findViewById(R.id.imageView1);
        img=(ImageView)findViewById(R.id.imageView2);

        loadingImg.setVisibility(View.VISIBLE);
        img.setVisibility(View.GONE);

        ImageLoading imgLoading=new ImageLoading();
        imgLoading.execute();
    }

    private class ImageLoading extends AsyncTask<Void, Void, Boolean>
    {
        @Override
        protected void onPreExecute() 
        {
            super.onPreExecute();
            loadingImg.getSettings().setJavaScriptEnabled(true);
            loadingImg.loadUrl("http://10.0.2.2/imgloading/showLoading.php");
            Log.i("img","pre");
        }

        @Override
        protected Boolean doInBackground(Void... params) 
        {
            Log.i("img","background");
            try
            {
                HttpClient client=new DefaultHttpClient();
                HttpGet request=new HttpGet("http://10.0.2.2/imgloading/getImage.php?id=2");
                HttpResponse response=client.execute(request);

                HttpEntity responseEntity=response.getEntity();
                final byte[] imgByteArray=EntityUtils.toByteArray(responseEntity);
                bitmap=BitmapFactory.decodeByteArray(imgByteArray, 0, imgByteArray.length);

                responseEntity.consumeContent();
                Log.i("img","inside try");

                return true;
            }
            catch(Exception e)
            {
                e.printStackTrace();
                Log.i("img","inside catch");
                Log.i("img", e.toString());
                return false;
            }
        }

        @Override
        protected void onPostExecute(Boolean result) 
        {
            super.onPostExecute(result);

            Log.i("img","post");
            if(result==true)
            {
                img.setVisibility(View.GONE);img.setVisibility(View.VISIBLE);
                Log.i("img","result true");
                img.setImageBitmap(bitmap);
            }
            else
            {
                img.setVisibility(View.GONE);img.setVisibility(View.GONE);
                Log.i("img","result false");
            }
        }
    }
}

activity_main.xml中

<WebView
    android:id="@+id/imageView1"
    android:layout_width="40dp"
    android:layout_height="40dp"
    android:layout_centerInParent="true"
    android:background="#f4f4f4" />

<ImageView
    android:id="@+id/imageView2"
    android:layout_width="100dp"
    android:layout_height="100dp"
    android:layout_centerInParent="true"
    android:visibility="invisible" />

在每个imageview中加载图像时加载进度条

1 个答案: