如何在Android中通过URL加载ImageView?
无论如何,人们会问我的意见,并将其发布为答案。我张贴。
URL newurl = new URL(photo_url_str);
mIcon_val = BitmapFactory.decodeStream(newurl.openConnection() .getInputStream());
profile_photo.setImageBitmap(mIcon_val);
谢谢。
你必须下载图像首先
public static Bitmap loadBitmap(String url) {
Bitmap bitmap = null;
InputStream in = null;
BufferedOutputStream out = null;
try {
in = new BufferedInputStream(new URL(url).openStream(), IO_BUFFER_SIZE);
final ByteArrayOutputStream dataStream = new ByteArrayOutputStream();
out = new BufferedOutputStream(dataStream, IO_BUFFER_SIZE);
copy(in, out);
out.flush();
final byte[] data = dataStream.toByteArray();
BitmapFactory.Options options = new BitmapFactory.Options();
//options.inSampleSize = 1;
bitmap = BitmapFactory.decodeByteArray(data, 0, data.length,options);
} catch (IOException e) {
Log.e(TAG, "Could not load Bitmap from: " + url);
} finally {
closeStream(in);
closeStream(out);
}
return bitmap;
}
然后使用Imageview.setImageBitmap设置位图到ImageView的
你说得对。但只有这三条线有助于解决问题。 URL newurl = new URL(photo_url_str); mIcon_val = BitmapFactory.decodeStream(newurl.openConnection() \t \t \t \t \t .getInputStream()); profile_photo.setImageBitmap(mIcon_val);感谢你的回复。 – Praveen 2010-03-19 08:57:04
对于URL - 导入java.net.URL; private static final int IO_BUFFER_SIZE = 4 * 1024; 最后一个是什么? – Steve 2010-03-19 12:07:29
看到这里的代码:http://stackoverflow.com/questions/3118691/android-make-an-image-at-a-url-equal-to-imageviews-image – OneWorld 2010-09-24 08:36:10
你也可以使用此LoadingImageView视图从URL中加载图像:
http://blog.blundellapps.com/imageview-with-loading-spinner/
一旦你添加了从该链接可以实例化一个URL图像视图类文件:
在XML:
<com.blundell.tut.LoaderImageView
android:id="@+id/loaderImageView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
image="http://developer.android.com/images/dialog_buttons.png"
/>
在代码:使用
final LoaderImageView image = new LoaderImageView(this, "http://developer.android.com/images/dialog_buttons.png");
和更新:
image.setImageDrawable("http://java.sogeti.nl/JavaBlog/wp-content/uploads/2009/04/android_icon_256.png");
public class LoadWebImg extends Activity {
String image_URL=
"http://java.sogeti.nl/JavaBlog/wp-content/uploads/2009/04/android_icon_256.png";
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
ImageView bmImage = (ImageView)findViewById(R.id.image);
BitmapFactory.Options bmOptions;
bmOptions = new BitmapFactory.Options();
bmOptions.inSampleSize = 1;
Bitmap bm = LoadImage(image_URL, bmOptions);
bmImage.setImageBitmap(bm);
}
private Bitmap LoadImage(String URL, BitmapFactory.Options options)
{
Bitmap bitmap = null;
InputStream in = null;
try {
in = OpenHttpConnection(URL);
bitmap = BitmapFactory.decodeStream(in, null, options);
in.close();
} catch (IOException e1) {
}
return bitmap;
}
private InputStream OpenHttpConnection(String strURL) throws IOException{
InputStream inputStream = null;
URL url = new URL(strURL);
URLConnection conn = url.openConnection();
try{
HttpURLConnection httpConn = (HttpURLConnection)conn;
httpConn.setRequestMethod("GET");
httpConn.connect();
if (httpConn.getResponseCode() == HttpURLConnection.HTTP_OK) {
inputStream = httpConn.getInputStream();
}
}
catch (Exception ex)
{
}
return inputStream;
}
}
非常感谢,我一直在寻找的完美例子................, 但错误主题这应该在这里==> [如何设置imageView的图像从一个字符串?](http://stackoverflow.com/questions/5254100/how-to-set-an-imageviews-image-from-a-string) – VenomVendor 2012-01-14 17:52:21
我写了一个类来处理这个问题,因为它似乎在我的各种项目中经常需要:
https://github.com/koush/UrlImageViewHelper
UrlImageViewHelper将填补 ImageView的与搜索 在URL的图像。
该示例将执行Google Image 异步搜索并加载/显示结果 。
UrlImageViewHelper将自动下载,保存并缓存所有的 图片,并将其映射到BitmapDrawables。 重复的网址不会被加载到 内存两次。通过使用弱基准散列表 来管理位图存储器 ,因此只要图像不再使用 ,它就会自动收集垃圾 。
这是什么牌子,顺便说一下? – 2012-04-13 17:21:15
@Shurane - Apache。我会在稍后记下它。 – koush 2012-04-16 17:48:25
看来我们需要使用这个,而不是https://github.com/koush/ion,因为UrlImageViewHelper已被弃用,如在github项目的页面上显示的https://github.com/koush/UrlImageViewHelper。 – 2015-01-12 15:34:08
我最近发现一个线程here,因为我必须做类似的事情与图像的列表视图,但原理很简单,你可以在那里所示(由jleedev)第一样品课堂上阅读。 你获得图像的输入流(来自网络)
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();
}
然后您存储图像绘制对象,你可以将它传递给ImageView的(通过setImageDrawable)。再次从上面的代码片段看看整个线程。
InputStream is = fetch(urlString);
Drawable drawable = Drawable.createFromStream(is, "src");
我的项目中没有DefaultHttpClient。 – 2015-11-28 08:16:34
您好我有最简单的代码试试这个
public class ImageFromUrlExample extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
ImageView imgView =(ImageView)findViewById(R.id.ImageView01);
Drawable drawable = LoadImageFromWebOperations("http://www.androidpeople.com/wp-content/uploads/2010/03/android.png");
imgView.setImageDrawable(drawable);
}
private Drawable LoadImageFromWebOperations(String url)
{
try{
InputStream is = (InputStream) new URL(url).getContent();
Drawable d = Drawable.createFromStream(is, "src name");
return d;
}catch (Exception e) {
System.out.println("Exc="+e);
return null;
}
}
}
为主。XML
<LinearLayout
android:id="@+id/LinearLayout01"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
xmlns:android="http://schemas.android.com/apk/res/android">
<ImageView
android:id="@+id/ImageView01"
android:layout_height="wrap_content"
android:layout_width="wrap_content"/>
试试这个
imageView.setImageBitmap(BitmapFactory.decodeStream(imageUrl.openStream()));//try/catch IOException and MalformedURLException outside
private Bitmap getImageBitmap(String url) {
Bitmap bm = null;
try {
URL aURL = new URL(url);
URLConnection conn = aURL.openConnection();
conn.connect();
InputStream is = conn.getInputStream();
BufferedInputStream bis = new BufferedInputStream(is);
bm = BitmapFactory.decodeStream(bis);
bis.close();
is.close();
} catch (IOException e) {
Log.e(TAG, "Error getting bitmap", e);
}
return bm;
}
// show The Image in a ImageView
new DownloadImageTask((ImageView) findViewById(R.id.imageView1))
.execute("http://java.sogeti.nl/JavaBlog/wp-content/uploads/2009/04/android_icon_256.png");
public void onClick(View v) {
startActivity(new Intent(this, IndexActivity.class));
finish();
}
private class DownloadImageTask extends AsyncTask<String, Void, Bitmap> {
ImageView bmImage;
public DownloadImageTask(ImageView bmImage) {
this.bmImage = bmImage;
}
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;
}
protected void onPostExecute(Bitmap result) {
bmImage.setImageBitmap(result);
}
}
确保您已在AndroidManifest.xml
设置以下的权限来访问ŧ他互联网。
<uses-permission android:name="android.permission.INTERNET" />
如果您是通过单击按钮加载图像,上述接受的答案是非常好的,但是如果您在新活动中进行加载,则会冻结UI一两秒。环顾四周,我发现一个简单的asynctask消除了这个问题。
要使用的AsyncTask在你活动的末尾添加这个类:
private class DownloadImageTask extends AsyncTask<String, Void, Bitmap> {
ImageView bmImage;
public DownloadImageTask(ImageView bmImage) {
this.bmImage = bmImage;
}
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;
}
protected void onPostExecute(Bitmap result) {
bmImage.setImageBitmap(result);
}
}
并使用来自您的onCreate()方法调用:
new DownloadImageTask((ImageView) findViewById(R.id.imageView1))
.execute(MY_URL_STRING);
结果是一个快速加载活动,根据用户的网络速度,稍后显示一秒的图像视图。
这是快速和紧凑。很好地满足了我的需求!谢谢! – 2013-01-17 01:25:07
真棒@凯尔。我喜欢你的榜样。 – 2013-05-28 05:13:20
太棒了。谢谢!!!! – 2013-08-16 00:53:37
String img_url= //url of the image
URL url=new URL(img_url);
Bitmap bmp;
bmp=BitmapFactory.decodeStream(url.openConnection().getInputStream());
ImageView iv=(ImageView)findviewById(R.id.imageview);
iv.setImageBitmap(bmp);
此代码已经过测试,它完全正常工作。
URL req = new URL(
"http://java.sogeti.nl/JavaBlog/wp-content/uploads/2009/04/android_icon_256.png"
);
Bitmap mIcon_val = BitmapFactory.decodeStream(req.openConnection()
.getInputStream());
很多很好的信息在这里......我最近发现了一个名为SmartImageView的类,它似乎目前工作得很好。非常容易并入和使用。
http://loopj.com/android-smart-image-view/
https://github.com/loopj/android-smart-image-view
更新:我最后写一个blog post about this,所以检查它使用SmartImageView帮助。
2ND UPDATE:我现在总是使用毕加索(见上),并强烈推荐它。 :)
这是一个较晚的答复,如上面建议AsyncTask
将会和谷歌搜索后有点我找到了一个更多的方式来解决这个问题。
my_image_view.setImageDrawable(Drawable.createFromStream((InputStream)new
URL(<String_url>).getContent(), "src"));
我自己试过,我还没有面对任何问题。
这实际上是非常好的极简主义!请记住,由于UI线程不允许网络操作,因此需要在额外的'Thread'中运行。 – creativecreatorormaybenot 2018-03-08 13:02:31
这将帮助你......
定义的ImageView和加载图像到它.....
Imageview i = (ImageView) vv.findViewById(R.id.img_country);
i.setImageBitmap(DownloadFullFromUrl(url));
然后定义这个方法:
public Bitmap DownloadFullFromUrl(String imageFullURL) {
Bitmap bm = null;
try {
URL url = new URL(imageFullURL);
URLConnection ucon = url.openConnection();
InputStream is = ucon.getInputStream();
BufferedInputStream bis = new BufferedInputStream(is);
ByteArrayBuffer baf = new ByteArrayBuffer(50);
int current = 0;
while ((current = bis.read()) != -1) {
baf.append((byte) current);
}
bm = BitmapFactory.decodeByteArray(baf.toByteArray(), 0,
baf.toByteArray().length);
} catch (IOException e) {
Log.d("ImageManager", "Error: " + e);
}
return bm;
}
任何容器中工作ImageView的,像列表视图网格视图,正常布局
private class LoadImagefromUrl extends AsyncTask< Object, Void, Bitmap > {
ImageView ivPreview = null;
@Override
protected Bitmap doInBackground(Object... params) {
this.ivPreview = (ImageView) params[0];
String url = (String) params[1];
System.out.println(url);
return loadBitmap(url);
}
@Override
protected void onPostExecute(Bitmap result) {
super.onPostExecute(result);
ivPreview.setImageBitmap(result);
}
}
public Bitmap loadBitmap(String url) {
URL newurl = null;
Bitmap bitmap = null;
try {
newurl = new URL(url);
bitmap = BitmapFactory.decodeStream(newurl.openConnection().getInputStream());
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return bitmap;
}
/** Usage **/
new LoadImagefromUrl().execute(imageView, url);
+1感谢您提供完整,简单的解决方案。 – PeteH 2014-03-02 21:00:05
版本与异常处理和异步任务:
AsyncTask<URL, Void, Boolean> asyncTask = new AsyncTask<URL, Void, Boolean>() {
public Bitmap mIcon_val;
public IOException error;
@Override
protected Boolean doInBackground(URL... params) {
try {
mIcon_val = BitmapFactory.decodeStream(params[0].openConnection().getInputStream());
} catch (IOException e) {
this.error = e;
return false;
}
return true;
}
@Override
protected void onPostExecute(Boolean success) {
super.onPostExecute(success);
if (success) {
image.setImageBitmap(mIcon_val);
} else {
image.setImageBitmap(defaultImage);
}
}
};
try {
URL url = new URL(url);
asyncTask.execute(url);
} catch (MalformedURLException e) {
e.printStackTrace();
}
对于这样的任务最好的现代化图书馆我的意见是Picasso由广场。它允许图像通过URL用一行代码加载到ImageView的:
Picasso.with(context).load("http://i.imgur.com/DvpvklR.png").into(imageView);
Picasso允许无障碍的图像加载在你的应用程序经常在一行代码!
使用摇篮:
compile 'com.squareup.picasso:picasso:2.5.2'
的代码只是一条线!图像加载Android上
Picasso.with(context).load("http://i.imgur.com/DvpvklR.png").into(imageView);
许多常见的陷阱是由Picasso
- 处理ImageView的回收和下载取消在适配器自动处理。
- 复杂的图像转换与最小的内存使用。
- 自动内存和磁盘缓存。
2。Glide图像加载和缓存库为Android专注于平滑滚动
使用摇篮:
repositories {
mavenCentral() // jcenter() works as well because it pulls from Maven Central
}
dependencies {
compile 'com.github.bumptech.glide:glide:3.7.0'
compile 'com.android.support:support-v4:19.1.0'
}
//对于一个简单的观点:
@Override public void onCreate(Bundle savedInstanceState) {
...
ImageView imageView = (ImageView) findViewById(R.id.my_image_view);
Glide.with(this).load("http://i.imgur.com/DvpvklR.png").into(imageView);
}
//对于一个简单的图片列表:
@Override public View getView(int position, View recycled, ViewGroup container) {
final ImageView myImageView;
if (recycled == null) {
myImageView = (ImageView) inflater.inflate(R.layout.my_image_view, container, false);
} else {
myImageView = (ImageView) recycled;
}
String url = myUrls.get(position);
Glide
.with(myFragment)
.load(url)
.centerCrop()
.placeholder(R.drawable.loading_spinner)
.crossFade()
.into(myImageView);
return myImageView;
}
因此,如果url是localhost,意味着图像在像xampp这样的开发系统本地服务器数据库中,我仍然可以从url =获取图像。 – blackjack 2014-06-09 10:31:22
这太棒了! – nemesisfixx 2014-08-13 11:08:25
@blackjack - 从应用程序本地主机将是智能手机本身。要访问开发中的系统,智能手机和开发系统必须位于同一网络中,并且您必须使用该网络中开发系统的IP地址。 – Ridcully 2015-02-15 07:02:35
试试这种方式,希望这会帮助你解决你的问题。
这里我将解释如何使用“AndroidQuery”外部库以asyncTask的方式从url/server加载图像,并将加载的图像缓存到设备文件或缓存区域。
- 下载“AndroidQuery”库from here
- 复制/粘贴这个罐子项目的lib文件夹并添加这个库项目构建路径
- 现在我展示演示,如何使用它。
activity_main.xml中
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center">
<FrameLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<ImageView
android:id="@+id/imageFromUrl"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:adjustViewBounds="true"/>
<ProgressBar
android:id="@+id/pbrLoadImage"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"/>
</FrameLayout>
</LinearLayout>
MainActivity.java
public class MainActivity extends Activity {
private AQuery aQuery;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
aQuery = new AQuery(this);
aQuery.id(R.id.imageFromUrl).progress(R.id.pbrLoadImage).image("http://itechthereforeiam.com/wp-content/uploads/2013/11/android-gone-packing.jpg",true,true);
}
}
Note : Here I just implemented common method to load image from url/server but you can use various types of method which can be provided by "AndroidQuery"to load your image easily.
试试这一个http://stackoverflow.com/questions/14332296/how-to-set图片来自网址使用asynctask/15797963#15797963 – comeGetSome 2013-04-07 16:27:17
使用毕加索... http://stackoverflow.com/a/23865531/3535286 – chiragkyada 2014-05-26 08:12:47
使用Glide http://www.gadgetsaint.com /android/circular-images-glide-library-android/#.WEj42rJ96Hs – ASP 2016-12-08 06:10:37