获取网络图片

<img src="https://img-blog.youkuaiyun.com/20150703195239222?watermark/2/text/aHR0cDovL2Jsb2cuY3Nkbi5uZXQv/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70/gravity/Center" width="300" height="500" alt="" />

1.访问网络要注意加上访问权限

<uses-permission android:name="android.permission.INTERNET"/>

2.将图片转化为流

public class MainActivity extends Activity {
    private EditText etImageUrl;
    private ImageView ivImage;
    public static final int SHOWIMAGE=1;
    private Handler handler=new Handler(){
    	public void handleMessage(android.os.Message msg) {
    		switch (msg.what) {
			case SHOWIMAGE:
				Bitmap bitmap=(Bitmap) msg.obj;
				ivImage.setImageBitmap(bitmap);
				break;

			default:
				break;
			}
    	};
    };

3.主要代码

public void viewImage(View view){
		final String imageUrl=etImageUrl.getText().toString();
		if(TextUtils.isEmpty(imageUrl)){
			Toast.makeText(this, "图片路径不能为空", Toast.LENGTH_LONG).show();
		}else{
			new Thread(){
				
					public void run() {
						try {
							URL url=new URL(imageUrl);
							HttpURLConnection httpURLConnection=(HttpURLConnection) url.openConnection();
						    httpURLConnection.setRequestMethod("GET");
						    httpURLConnection.setConnectTimeout(5000);
						    int responseCode=httpURLConnection.getResponseCode();
						    if(responseCode==200){
						    	InputStream inputStream=httpURLConnection.getInputStream();
						    	Bitmap bitmap=BitmapFactory.decodeStream(inputStream);
						    	Message message=new Message();
						    	message.what=SHOWIMAGE;
						    	message.obj=bitmap;
						    	//ivImage.setImageBitmap(bitmap);
						    	handler.sendMessage(message);
						    }else{
						    	Toast.makeText(MainActivity.this, "显示图片失败", Toast.LENGTH_LONG).show();
						    }
						} catch (MalformedURLException e) {
							e.printStackTrace();
						} catch (IOException e) {
							e.printStackTrace();
						}
					
				}
			}.start();
			
		}
	}

}