[连载 7/15] Android 从入门到精通Example 之 URL Image Display

本文介绍了一个Android应用示例，该应用分为两部分：一是从网络获取并显示一张图片；二是通过ACTION_VIEW标准活动操作来启动浏览器访问指定网址。示例中详细展示了如何通过Intent实现上述功能。

显示一副图片，使用标准activity action ACTION_VIEW 调用browser打开一个网页的例子。

irst part of this example shows how to display an image on the screen. The image is retrieved from a web location. The second part of this example shows how to create an intent using one of the standard activity action (ACTION_VIEW) to view a web page using the browser.

1. DowloadEx.java

public class DownloadEX extends Activity { private static final String TAG = "DownloadEx"; private ImageView photo; private EditText urlBox; private EditText webPageBox; private Button showButton, goButton; /** Called when the activity is first created. */ @Override public void onCreate(Bundle icicle) { super.onCreate(icicle); setContentView(R.layout.main); webPageBox = (EditText) findViewById(R.id.webpage); webPageBox.setText("http://www.cs.clemson.edu/~pargas"); urlBox = (EditText) findViewById(R.id.url); urlBox.setText("http://www.cs.clemson.edu/~pargas/pargas.jpg"); photo = (ImageView) findViewById(R.id.image1); showButton = (Button) findViewById(R.id.showButton); goButton = (Button) findViewById(R.id.goButton); showButton.setOnClickListener(new View.OnClickListener() { public void onClick(View v) { try { /* get the picture from the web */ URL imageURL = new URL(urlBox.getText().toString()); Drawable urlImage = Drawable.createFromStream(imageURL.openStream(), ""); photo.setImageDrawable(urlImage); } catch (Exception e) { Log.e(TAG, "Error found: "+e); } } }); goButton.setOnClickListener(new View.OnClickListener() { public void onClick(View v) { Intent visitWeb = new Intent (Intent.ACTION_VIEW, Uri.parse (webPageBox.getText().toString())); startActivity (visitWeb); } }); } }