将网址中的图片添加到自定义InfoWindow谷歌地图v2中

Question

我正在使用Android应用程序.用户在谷歌地图上搜索餐馆.在谷歌地图显示所有邻居的餐厅标记.如果他点击标记,它会显示自定义InfoWindow.我的问题是我无法加载返回谷歌的图像.我正确的图像的网址,但我不能在窗口显示它.

信息窗口

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
android:background="@color/bg_color" >

<ImageView
        android:id="@+id/place_icon"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:focusable="false"" />

<TextView
    android:id="@+id/place_title"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content" />

<TextView
    android:id="@+id/place_vicinity"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content" />

<LinearLayout 
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:orientation="horizontal"
    android:background="@color/bg_color" >

    <RatingBar
         android:id="@+id/place_rating"
         style="?android:attr/ratingBarStyleSmall"
         android:numStars="5"
         android:rating="0"
         android:isIndicator="false"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="5dip" />

    <ImageView
        android:id="@+id/navigate_icon"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:focusable="false"
        android:src="@drawable/navigate" />

</LinearLayout>

在创造我有这个

mGoogleMap.setInfoWindowAdapter(new InfoWindowAdapter() {

            // Use default InfoWindow frame
            @Override
            public View getInfoWindow(Marker arg0) {
                return null;
            }

            // Defines the contents of the InfoWindow
            @Override
            public View getInfoContents(Marker arg0) {

                // Getting view from the layout file info_window_layout
                View v = getLayoutInflater().inflate(R.layout.info_window_layout, null);

                // Getting the snippet from the marker
                String snippet = arg0.getSnippet();

                // Getting the snippet from the marker
                String titlestr = arg0.getTitle();

                String cutchar1= "%#";
                String cutchar2= "%##";
                String ratingstr = snippet.substring(0,snippet.indexOf( cutchar1 ));
                String vicinitystr = snippet.substring(snippet.indexOf( cutchar1 )+2, snippet.indexOf( cutchar2 ) );
                String iconurl= snippet.substring(snippet.indexOf( cutchar2 )+3);

                // Getting reference to the TextView to set latitude
                TextView title = (TextView) v.findViewById(R.id.place_title);

                TextView vicinity = (TextView) v.findViewById(R.id.place_vicinity);

                ImageView image = (ImageView) v.findViewById(R.id.navigate_icon);

                // Setting the latitude
                title.setText(titlestr);

                // declare RatingBar object
                RatingBar rating=(RatingBar) v.findViewById(R.id.place_rating);// create RatingBar object
                if( !(ratingstr.equals("null")) ){
                    rating.setRating(Float.parseFloat(ratingstr));
                }
                vicinity.setText(vicinitystr);                  

                final DownloadImageTask download = new DownloadImageTask((ImageView) v.findViewById(R.id.place_icon) ,arg0);
                download.execute(iconurl);
                // Returning the view containing InfoWindow contents
                return v;

            }

});

而DownloadImage代码是:

private class DownloadImageTask extends AsyncTask<String, Void, Bitmap> {
      ImageView bmImage;
      Marker marker;
      boolean refresh;

      public DownloadImageTask(final ImageView bmImage, final Marker marker) {
          this.bmImage = bmImage;
          this.marker=marker;
          this.refresh=false;
      }

     public void SetRefresh(boolean refresh ){
         this.refresh=true;

     }

    /*  @Override
      protected void onPreExecute() 
      {
          super.onPreExecute();
          bmImage.setImageBitmap(null);
      }*/

      @Override
      protected Bitmap doInBackground(String... urls) {
          String urldisplay = urls[0];
          Bitmap mIcon11 = null;
          try {
            InputStream in = new java.net.URL(urldisplay).openStream();
            mIcon11 = BitmapFactory.decodeStream(in);
          } catch (Exception e) {
              Log.e("Error", e.getMessage());
              e.printStackTrace();
          }
          return mIcon11;
      }
      @Override
      protected void onPostExecute(Bitmap result) {
          if(!refresh){
              SetRefresh(refresh);
              bmImage.setImageBitmap(result);
              marker.showInfoWindow();
          }
      }
    }

最后,当我执行代码并点击标记时,getInfoContents不会停止执行,并且不会出现图标.

为什么会这样？

Answer 1

我一直在构建一个类似的应用程序.

首先,InfoWindow没有显示下载图像的原因是因为MapFragment将视图呈现为a Canvas,然后绘制它.您在信息窗口中看到的不是您创建的视图,而是它们的"图片"或"屏幕截图".你基本上需要showInfoWindow()再次调用该Marker对象,这将重新渲染,Canvas现在你的图像可见.

然而,话虽如此,根据我的经验,Bitmap从URL 加载然后设置它不是最好的解决方案.Android不能Bitmap很好地处理.加载几个位图后,OutOfMemoryError异常只是时间问题,具体取决于您拥有的系统内存量.

我建议使用Picasso库来处理异步下载和缓存(在内存和磁盘中),并使实际图像只加载一行(Picasso.with(context).load("http://i.imgur.com/DvpvklR.png").into(imageView);).(更多信息请访问http://square.github.io/picasso/)

之前的答案很好,除了正如他所说的那样,"延迟"对我来说有点太神奇了.Picasso可以选择使用回调,我建议使用它(我在我的应用程序中使用它).

首先创建一个实现Picasso Callback接口的类(它可以在您的活动内部),并Marker在构造函数中接收一个(因此您可以showInfoWindow()再次调用该标记).

private class InfoWindowRefresher implements Callback {
   private Marker markerToRefresh;

   private InfoWindowRefresher(Marker markerToRefresh) {
        this.markerToRefresh = markerToRefresh;
    }

    @Override
    public void onSuccess() {
        markerToRefresh.showInfoWindow();
    }

    @Override
    public void onError() {}
}

信息窗口如下所示:

mMap.setInfoWindowAdapter(new GoogleMap.InfoWindowAdapter() {
    @Override
    public View getInfoWindow(Marker marker) {
        // inflate view window

        // set other views content

        // set image view like this:
        if (not_first_time_showing_info_window) {
            Picasso.with(ActivityClass.this).load(restaurantPictureURL).into(imgInfoWindowPicture);
        } else { // if it's the first time, load the image with the callback set
            not_first_time_showing_info_window=true;
            Picasso.with(ActivityClass.this).load(restaurantPictureURL).into(imgInfoWindowPicture,new InfoWindowRefresher(marker));
        }

        return v;
    }

    @Override
    public View getInfoContents(Marker marker) {
        return null;
    }
});

你可以看到,回调非常简单.但是,当使用这种方法时,你必须小心只在第一次调用中使用回调,而不是在后续调用中使用(我只是not_first_time_showing_info_window为了反映这个想法而设置...你必须看看如何将它包含在你的程序逻辑.如果你不这样做,Picasso回调将调用showInfoWindow(),这将重新调用回调,这将召回showInfoWindow()......好吧,你可以看到递归的去向.:)

主要的是让Picasso加载回调只运行一次,然后在后续调用中没有回调.

Answer 2

我使用黑魔法(也就是设置延迟)解决了这个问题.我利用了Picasso的缓存,并在初始加载开始后几毫秒刚刚调用了showInfoWindow.

这是我的CustomWindowAdapter.

class CustomWindowAdapter implements InfoWindowAdapter{
   LayoutInflater mInflater;
   Map<Marker, String> imageStringMapMarker;
   Context context;

   public CustomWindowAdapter(LayoutInflater i,  Map<Marker, String> imageStringMapMarker2, Context context ){
      mInflater = i;
      imageStringMapMarker = imageStringMapMarker2;
   }

   @Override
   public View getInfoContents(final Marker marker) {

      View v = mInflater.inflate(R.layout.custom_info_window, null);

      ImageView ivThumbnail = (ImageView) v.findViewById(R.id.ivThumbnail);
      String urlImage = imageStringMapMarker.get(marker).toString();
      Picasso.with(context).load(Uri.parse(urlImage)).resize(250,250).into(ivThumbnail);

      return v;

   }

   @Override
   public View getInfoWindow(Marker marker) {
    // TODO Auto-generated method stub
     return null;
   }
}

这是在我的主要活动中调用信息窗口的方法,我实现了延迟.

myMap.setInfoWindowAdapter(new CustomWindowAdapter(this.getLayoutInflater(),
imageStringMapMarker, getApplicationContext()));
myMap.setOnMarkerClickListener(new OnMarkerClickListener() {

    @Override
    public boolean onMarkerClick(final Marker mark) {


    mark.showInfoWindow();

        final Handler handler = new Handler();
        handler.postDelayed(new Runnable() {
            @Override
            public void run() {
                mark.showInfoWindow();

            }
        }, 200);

        return true;
    }
});

Answer 3

无论你从getInfoContents()哪里返回,都会被转换为a Bitmap并用于显示结果.直到稍后,下载完成时,您才会显示图像,此时Bitmap已经创建并使用了该图像.

您需要getInfoContents()在调用之前下载图像.