TextView加载Html时使用ImageGetter加载图片缓慢

G.Gentle 2016-03-22 10:21:15

最近在做一个论坛，每个帖子回复的内容为html，我用TextView加载，但是图片很慢，需要等很久才会出来，求大神帮忙看看代码是否有问题。

首先是ImageGetter的代码：



import java.io.IOException;

import java.io.InputStream;

import java.net.MalformedURLException;



import org.apache.http.HttpResponse;

import org.apache.http.client.methods.HttpGet;

import org.apache.http.impl.client.DefaultHttpClient;



import android.content.Context;

import android.graphics.drawable.Drawable;

import android.os.AsyncTask;

import android.text.Html.ImageGetter;

import android.view.View;

import android.widget.TextView;



public class URLImageParser implements ImageGetter {

	Context c;

	View container;

	TextView mTextView;



	/***

	 * Construct the URLImageParser which will execute AsyncTask and refresh the

	 * container

	 * 

	 * @param t

	 * @param c

	 */

	public URLImageParser(View t, Context c,TextView textView) {

		this.mTextView = textView;

		this.c = c;

		this.container = t;

	}



	public Drawable getDrawable(String source) {

		URLDrawable urlDrawable = new URLDrawable(c);



		// get the actual source

		ImageGetterAsyncTask asyncTask = new ImageGetterAsyncTask(urlDrawable);



		asyncTask.execute(source);



		// return reference to URLDrawable where I will change with actual image

		// from

		// the src tag

		return urlDrawable;

	}



	public class ImageGetterAsyncTask extends AsyncTask<String, Void, Drawable> {

		URLDrawable urlDrawable;



		public ImageGetterAsyncTask(URLDrawable d) {

			this.urlDrawable = d;

		}



		@Override

		protected Drawable doInBackground(String... params) {

			String source = params[0];

			return fetchDrawable(source);

		}



		@Override

		protected void onPostExecute(Drawable result) {

			// set the correct bound according to the result from HTTP call

			try {

				urlDrawable.setBounds(0, 0, 0 + result.getIntrinsicWidth() * 3,

						0 + result.getIntrinsicHeight() * 3);



				// change the reference of the current drawable to the result

				// from the HTTP call

				urlDrawable.drawable = result;



				// redraw the image by invalidating the container

				URLImageParser.this.container.invalidate();

//				mTextView.invalidate();

				mTextView.setText(mTextView.getText());

			} catch (Exception e) {

				// TODO: handle exception

			}

		}



		/***

		 * Get the Drawable from URL

		 * 

		 * @param urlString

		 * @return

		 */

		public Drawable fetchDrawable(String urlString) {

			try {

				InputStream is = fetch(urlString);

				Drawable drawable = Drawable.createFromStream(is, "src");

				drawable.setBounds(0, 0, 0 + drawable.getIntrinsicWidth() * 3,

						0 + drawable.getIntrinsicHeight() * 3);

				return drawable;

			} catch (Exception e) {

				return null;

			}

		}



		private InputStream fetch(String urlString)

				throws MalformedURLException, IOException {

			DefaultHttpClient httpClient = new DefaultHttpClient();

			HttpGet request = new HttpGet(urlString);

			HttpResponse response = httpClient.execute(request);

			return response.getEntity().getContent();

		}

	}

}

然后URLDrawable类的代码：



import com.yifang.house.R;



import android.app.Activity;

import android.content.Context;

import android.graphics.Canvas;

import android.graphics.Rect;

import android.graphics.drawable.BitmapDrawable;

import android.graphics.drawable.Drawable;

import android.view.Display;



public class URLDrawable extends BitmapDrawable {

	// the drawable that you need to set, you could set the initial drawing

	// with the loading image if you need to

	protected Drawable drawable;



	@SuppressWarnings("deprecation")

	public URLDrawable(Context context) {

		this.setBounds(getDefaultImageBounds(context));

		drawable = context.getResources().getDrawable(R.drawable.ic_launcher);

		drawable.setBounds(getDefaultImageBounds(context));

	}



	@Override

	public void draw(Canvas canvas) {

		// override the draw to facilitate refresh function later

		if (drawable != null) {

			drawable.draw(canvas);

		}

	}



	@SuppressWarnings("deprecation")

	public Rect getDefaultImageBounds(Context context) {

		Display display = ((Activity) context).getWindowManager()

				.getDefaultDisplay();

		int width = display.getWidth();

		int height = (int) (width * 3 / 4);

		Rect bounds = new Rect(0, 0, width, height);

		return bounds;

	}

}

最后是在adapter里面调用的代码：

URLImageParser p = new URLImageParser(h.subjectTv, mContext,

					h.subjectTv);

			Spanned htmlSpan = Html.fromHtml(content, p, null);

			h.subjectTv.setText(htmlSpan);

每个回帖的图片加载太慢了，一分钟左右才会出来，求大神帮忙解决，感激不尽