来源: 互联网  发布时间: 2014-02-18

ndroid显示在线图片

import java.io.ByteArrayOutputStream;  
import java.io.InputStream;  
import java.net.HttpURLConnection;  
import java.net.URL;  
  
import android.app.Activity;  
import android.graphics.Bitmap;  
import android.graphics.BitmapFactory;  
import android.os.Bundle;  
import android.view.View;  
import android.widget.Button;  
import android.widget.EditText;  
import android.widget.ImageView;  
import android.widget.Toast;  
  
public class AndroidTest extends Activity {  
    private static final String URL = "http://avatar.csdn.net/3/2/4/2_ameyume.jpg";  
    private EditText pathText;  
    private ImageView imageView;  
  
    /** Called when the activity is first created. */  
    @Override  
    public void onCreate(Bundle savedInstanceState) {  
        super.onCreate(savedInstanceState);  
        setContentView(R.layout.main);  
          
        pathText = (EditText) this.findViewById(R.id.path);  
        pathText.setText(URL);  
        imageView = (ImageView) this.findViewById(R.id.imageView);  
        Button button = (Button) this.findViewById(R.id.button);  
        button.setOnClickListener(new View.OnClickListener() {  
              
            public void onClick(View v) {  
                String path = pathText.getText().toString();  
                try {  
                    byte[] data = getImage(path);  
                    if(data!=null){  
                        Bitmap bitmap = BitmapFactory.decodeByteArray(data, 0, data.length);// bitmap  
                        imageView.setImageBitmap(bitmap);// display image  
                    }else{  
                        Toast.makeText(AndroidTest.this, "Image error!", 1).show();  
                    }  
                } catch (Exception e) {  
                    Toast.makeText(AndroidTest.this,"Newwork error!", 1).show();  
                    e.printStackTrace();  
                }  
            }  
        });  
  
    }  
  
    /** 
     * Get image from newwork 
     * @param path The path of image 
     * @return 
     * @throws Exception 
     */  
    public static byte[] getImage(String path) throws Exception{  
        URL url = new URL(/blog_article/path/index.html);  
        HttpURLConnection conn = (HttpURLConnection) url.openConnection();  
        conn.setConnectTimeout(5 * 1000);  
        conn.setRequestMethod("GET");  
        InputStream inStream = conn.getInputStream();  
        if(conn.getResponseCode()==200){  
            return readStream(inStream);  
        }  
        return null;  
    }  
  
    /** 
     * Get data from stream 
     * @param inStream 
     * @return 
     * @throws Exception 
     */  
    public static byte[] readStream(InputStream inStream) throws Exception{  
        ByteArrayOutputStream outStream = new ByteArrayOutputStream();  
        byte[] buffer = new byte[1024];  
        int len = 0;  
        while( (len=inStream.read(buffer)) != -1){  
            outStream.write(buffer, 0, len);  
        }  
        outStream.close();  
        inStream.close();  
        return outStream.toByteArray();  
    }  
  
}  

manifest.xml中增加网络权限

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

    

    来源: 互联网  发布时间: 2014-02-18

利用ScrollView实现布局自动滚动
首先1，获得ScrollView sc = (ScrollView) findViewById(R.id.scroll);//scroll对象
     LinearLayout mlayout = (LinearLayout) findViewById(R.id.mlayout);//scrollView中包含的布局对象
2，定义一个Handler
private final Handler mHandler = new Handler();
3,实现一个线程

        private Runnable ScrollRunnable= new Runnable() {
                @Override
                public void run() {
                         int off = mlayout.getMeasuredHeight() - sc.getHeight();//判断高度      
 if (off > 0) {
                                sc.scrollBy(0, 30);
                                if (sc.getScrollY() == off) {
                                        Thread.currentThread().interrupt();
                                } else {
                                        mHandler.postDelayed(this, 1000);
                                }
                        }
                }
        };

4，开始滚动
mHandler.post(ScrollRunnable);

5，暂停滚动
mHandler.removeCallbacks(ScrollRunnable);

ScrollView强制滑到底部
scroll.fullScroll(View.FOCUS_DOWN)

    

    来源: 互联网  发布时间: 2014-02-18

layout中设置图片自适应大小，并且设置最大宽高
ayout中设置图片自适应大小，并且设置最大宽高，当图片的宽高大于设置的最大值时，宽高值为设置的最大值。

<ImageView android:id="@+id/image_view"    
      android:layout_width="wrap_content"  
      android:layout_height="wrap_content"  
      android:adjustViewBounds="true"  
      android:maxWidth="42dp"  
      android:maxHeight="42dp"  
      android:scaleType="fitCenter"  
      android:layout_marginLeft="3dp"  
      android:src="/blog_article/@drawable/icon/index.html"  
      />  

关键代码：

        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:adjustViewBounds="true"
        android:maxWidth="42dp"
        android:maxHeight="42dp"