学习Android之SimpleAdapter显示网络图片

效果图：

此程序主要的知识点是：SimpleAdapter本身是不支持网络图片的， 如果在Map.put（a，b）中 b为一个Bitmap，程序不会报红色字体，而是在控制台输出绿色的字体，如下

05-10 15:46:45.474: I/System.out(846): resolveUri failed on bad bitmap uri: android.graphics.Bitmap@43e40c08

要想实现显示网络图片其实很简单，使用SimpleAdapter中的方法simpleAdapter.setViewBinder（）。

simpleAdapter.setViewBinder(new ViewBinder() {

			@Override
			public boolean setViewValue(View view, Object data,
					String textRepresentation) {
				if (view instanceof ImageView && data instanceof Bitmap) {
					ImageView iv = (ImageView) view;
					iv.setImageBitmap((Bitmap) data);
					return true;
				}
				return false;
			}
		});

new SimpleAdapter(MainActivity.this,getData(), R.layout.t, new String[] { "images" },new int[] { R.id.ImageVIew_main });

list>（如上getData()方法，返回一个list>），程序会遍历每一项数据。接下来用if（）语句筛选就可以了。

既然是网络图片，那就需要权限

代码如下：

MainActivity.java

public class MainActivity extends ActionBarActivity {


	ListView listView;
	List> data;

	String str[] = { "",       //自己添加图片网址 h  t  t  p ://
			"",
			"",
			"" };

	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		listView = (ListView) findViewById(R.id.LV_main);

		SimpleAdapter simpleAdapter = new SimpleAdapter(MainActivity.this,
				getData(), R.layout.t, new String[] { "images" },
				new int[] { R.id.ImageVIew_main });
		simpleAdapter.setViewBinder(new ViewBinder() {

			@Override
			public boolean setViewValue(View view, Object data,
					String textRepresentation) {
				if (view instanceof ImageView && data instanceof Bitmap) {
					ImageView iv = (ImageView) view;
					iv.setImageBitmap((Bitmap) data);
					return true;
				}
				return false;
			}
		});

		listView.setAdapter(simpleAdapter);
	}

	public List> getData() {
		data = new ArrayList>();
		for (int i = 0; i  map = new HashMap();

			map.put("images", returnBitMap(str[i]));
			data.add(map);
		}
		return data;

	}

	public Bitmap returnBitMap(String url) {
		URL myFileUrl = null;
		Bitmap bitmap = null;
		try {
			myFileUrl = new URL(url);
		} catch (MalformedURLException e) {
			e.printStackTrace();
		}
		try {
			HttpURLConnection cOnn= (HttpURLConnection) myFileUrl
					.openConnection();
			conn.setDoInput(true);
			conn.connect();
			InputStream is = conn.getInputStream();
			bitmap = BitmapFactory.decodeStream(is);
			is.close();
		} catch (IOException e) {
			e.printStackTrace();
		}
		return bitmap;
	}
}

t.xml

学习Android之SimpleAdapter显示网络图片,,

学习Android之SimpleAdapter显示网络图片