Android如何從網址加載圖片並將其放在頂部

Question

其實我已經完成了「從網址加載」部分，但結果並不令人滿意。

我將圖像放置在頂部。但是，當它加載圖像時，它會自動對齊到中心，但我已聲明android:layout_alignParentTop="true"。

此外，我想有形象上的一些文本，但文本總是在左上角..........

這裏是我的代碼： （XML）

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" 
    xmlns:tools="http://schemas.android.com/tools" 
    android:id="@+id/list_detail" 
    android:layout_width="match_parent" 
    android:layout_height="match_parent"  
    > 


    <ImageView 
     android:id="@+id/product_image" 
     android:layout_width="match_parent" 
     android:layout_height="wrap_content" 
     android:layout_alignParentTop="true" 
     android:src="@drawable/white" /> 


    <TextView 
     android:id="@+id/product_price" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:layout_below="@+id/product_image" 
     android:text="@string/hello_world" /> 

    <TextView 
     android:id="@+id/product_title" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:layout_below="@+id/product_price" 
     android:text="@string/hello_world" /> 


</RelativeLayout> 

活動：

import java.io.IOException; 
import java.io.InputStream; 

import org.apache.http.HttpEntity; 
import org.apache.http.HttpResponse; 
import org.apache.http.client.ClientProtocolException; 
import org.apache.http.client.HttpClient; 
import org.apache.http.client.methods.HttpGet; 
import org.apache.http.entity.BufferedHttpEntity; 
import org.apache.http.impl.client.DefaultHttpClient; 

import android.app.Activity; 
import android.content.Intent; 
import android.database.Cursor; 
import android.database.sqlite.SQLiteDatabase; 
import android.graphics.Bitmap; 
import android.graphics.BitmapFactory; 
import android.os.AsyncTask; 
import android.os.Bundle; 
import android.support.v4.app.NavUtils; 
import android.text.Html; 
import android.util.Log; 
import android.view.Menu; 
import android.view.MenuItem; 
import android.widget.ImageView; 
import android.widget.TextView; 

public class PostDetail extends Activity{ 
    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.list_detail); 

     getActionBar().setDisplayHomeAsUpEnabled(true); 

     WPTemplateDB dpOpener = new WPTemplateDB(this); 
     SQLiteDatabase db = dpOpener.getReadableDatabase(); 
     //Log.d("passed pid", getIntent().getStringExtra("pid")+""); 
     Cursor cursor = db.query(WPTemplateDB.PRODUCT_TABLE, 
           new String[]{WPTemplateDB.TITLE, WPTemplateDB.IMAGE, WPTemplateDB.PRICE}, 
           WPTemplateDB.PRODUCT_ID+"=?", 
           new String[]{getIntent().getStringExtra("pid")}, 
           null, null, null); 
     String title = "", price = "", img = ""; 
     while (cursor.moveToNext()){ 
      title = cursor.getString(0);    
      img = cursor.getString(1); 
      price = cursor.getString(2); 
     } 
     Log.d("title", title); 
     Log.d("img_src", img); 
     TextView productTitle = (TextView)findViewById(R.id.product_title); 
     ImageView productImage = (ImageView)findViewById(R.id.product_image); 
     TextView productPrice = (TextView)findViewById(R.id.product_price); 

     new LoadImageFromURL(productImage).execute(img); 
     productTitle.setText(Html.fromHtml(title),TextView.BufferType.SPANNABLE);  
     productPrice.setText(price); 
    } 

    private class LoadImageFromURL extends AsyncTask<String, Void, Bitmap>{ 
     ImageView bitmapImgView; 
     public LoadImageFromURL(ImageView bmImgView){ 
      bitmapImgView = bmImgView; 
     } 

     @Override 
     protected Bitmap doInBackground(String... params) { 
      // TODO Auto-generated method stub 
      String urlStr = params[0]; 
      Bitmap img = null; 

      HttpClient client = new DefaultHttpClient(); 
      HttpGet request = new HttpGet(urlStr); 
      HttpResponse response; 
      try { 
       response = (HttpResponse)client.execute(request);   
       HttpEntity entity = response.getEntity(); 
       BufferedHttpEntity bufferedEntity = new BufferedHttpEntity(entity); 
       InputStream inputStream = bufferedEntity.getContent(); 
       img = BitmapFactory.decodeStream(inputStream); 
      } catch (ClientProtocolException e) { 
       // TODO Auto-generated catch block 
       e.printStackTrace(); 
      } catch (IOException e) { 
       // TODO Auto-generated catch block 
       e.printStackTrace(); 
      } 
      return img; 
     } 

     @Override 
     protected void onPostExecute(Bitmap bitmap){ 
      bitmapImgView.setImageBitmap(bitmap); 
     } 
    } 

    @Override 
    public boolean onCreateOptionsMenu(Menu menu) { 

     // Inflate the menu; this adds items to the action bar if it is present. 
     getMenuInflater().inflate(R.menu.list_post, menu); 
     return true; 
    } 

    @Override 
    public boolean onOptionsItemSelected(MenuItem item) { 
     int id = item.getItemId(); 
     if (id == android.R.id.home) { 
      // This ID represents the Home or Up button. In the case of this 
      // activity, the Up button is shown. Use NavUtils to allow users 
      // to navigate up one level in the application structure. For 
      // more details, see the Navigation pattern on Android Design: 
      // 
      // http://developer.android.com/design/patterns/navigation.html#up-vs-back 
      // 
      NavUtils.navigateUpTo(this, 
        new Intent(this, ListPost.class)); 
      return true; 
     } 
     return super.onOptionsItemSelected(item); 
    } 
} 

Answer 1

您應該使用WRAP_CONTENT代替match_parent爲product_image的android：layout_width，你應該使用FrameLayout裏，如果你想將文本上的Imag EVIEW。如：

 <FrameLayout 
      android:layout_width="wrap_content" 
      android:layout_height="wrap_content"> 

      <ImageView 
       android:layout_width="wrap_content" 
       android:src="@drawable/ic_launcher" 
       android:layout_height="wrap_content" /> 

      <TextView 
       android:layout_width="wrap_content" 
       android:text="test" 
       android:layout_height="wrap_content" /> 

     </FrameLayout>