开启新线程获取网络图片并显示到ImageView中

偏执的太偏执、 2022-08-19 13:20 173阅读 0赞

1、布局文件

<?xml version="1.0" encoding="utf-8"?>
    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent" >
    
        <ImageView
            android:id="@+id/imageView1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:padding="10dp"
            android:src="@drawable/hint" />
    </LinearLayout>

2、MainActivity

public class MainActivity extends Activity {
    
    	private ImageView iv;//声明ImageView组件的对象
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
            iv = (ImageView)findViewById(R.id.imageView1);//获取布局管理器中添加的ImageView
            //创建一个新线程，用于从网络上获取图片
            new Thread(new Runnable() {
    			@Override
    			public void run() {
    				//从网络上获取图片
    				final Bitmap bitmap = getPicture("http://img.woyaogexing.com/2014/08/15/0e0875831a1790e3!200x200.jpg");
    				try {
    					Thread.sleep(2000);//线程休眠2秒钟
    				} catch (InterruptedException e) {
    					e.printStackTrace();
    				}
    				//发送一个对象
    				iv.post(new Runnable() {
    					@Override
    					public void run() {
    						iv.setImageBitmap(bitmap);//在ImageView中显示从网络上获取到的图片
    					}
    				});
    			}
    		}).start();//开启线程
        }
        /**
         * 根据网址获取图片对应的Bitmap对象
         */
        public Bitmap getPicture(String path){
        	Bitmap bm = null;
        	try {
    			URL url = new URL(path);//创建URL对象
    			URLConnection conn = url.openConnection();//获取URL对象对应的连接
    			conn.connect();//打开连接
    			InputStream is = conn.getInputStream();//获取输入流对象
    			bm = BitmapFactory.decodeStream(is);//根据输入流对象创建bitmap对象
    		} catch (MalformedURLException e1) {
    			e1.printStackTrace();
    		}catch (IOException e) {
    			e.printStackTrace();
    		}
        	return bm;
        }
    }

3、权限

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

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[Center 1]: /images/20220731/91f5b99f56a440d28337ae327a266cca.png