2012-01-12 93 views
8

如何從InputStream(資產,文件系統)加載drawable並基於屏幕分辨率hdpi,mdpi或ldpi動態調整其大小?Android負載以編程方式繪製並調整大小

原始圖像是在hdpi中,我只需要調整大小爲mdpi和ldpi。

有誰知道Android如何動態調整/ res中的drawables的大小?

+0

出於好奇,有什麼理由不預上漿它(爲'mdpi'和'ldpi')並在'res'目錄中鏈接到它? – 2012-01-12 15:45:58

+0

從網絡下載的圖像。我可以在服務器上執行預處理,但下載速度會變慢。 – peceps 2012-01-12 15:48:42

回答

4

發現:

/** 
    * Loads image from file system. 
    * 
    * @param context the application context 
    * @param filename the filename of the image 
    * @param originalDensity the density of the image, it will be automatically 
    * resized to the device density 
    * @return image drawable or null if the image is not found or IO error occurs 
    */ 
    public static Drawable loadImageFromFilesystem(Context context, String filename, int originalDensity) { 
    Drawable drawable = null; 
    InputStream is = null; 

    // set options to resize the image 
    Options opts = new BitmapFactory.Options(); 
    opts.inDensity = originalDensity; 

    try { 
     is = context.openFileInput(filename); 
     drawable = Drawable.createFromResourceStream(context.getResources(), null, is, filename, opts);   
    } catch (Throwable e) { 
     // handle 
    } finally { 
     if (is != null) { 
     try { 
      is.close(); 
     } catch (Throwable e1) { 
      // ingore 
     } 
     } 
    } 
    return drawable; 
    } 

使用這樣的:

loadImageFromFilesystem(context, filename, DisplayMetrics.DENSITY_MEDIUM); 
+1

Unfortunatley此代碼不適用於HTC Desire HD和HTC Evo。在此處查看解決方案:http://stackoverflow.com/questions/7747089/exception-in-drawable-createfromresourcestream-htc-only/9195531#9195531 – peceps 2012-02-08 14:46:47

1

如果你想顯示的圖像,但不幸的是這個形象是大尺寸的,讓例子,你要顯示的圖像以30乘30的格式,然後檢查它的大小,如果它大於你的要求大小,然後除以你的數量(在這裏是30 * 30),然後你再次拿到並用來再次分割圖像區域。

drawable = this.getResources().getDrawable(R.drawable.pirImg); 
int width = drawable.getIntrinsicWidth(); 
int height = drawable.getIntrinsicHeight(); 
if (width > 30)//means if the size of an image is greater than 30*30 
{ 
    width = drawable.getIntrinsicWidth()/30; 
    height = drawable.getIntrinsicWidth()/30; 
} 

drawable.setBounds(
    0, 0, 
    drawable.getIntrinsicWidth()/width, 
    drawable.getIntrinsicHeight()/height); 

//and now add the modified image in your overlay 
overlayitem[i].setMarker(drawable) 
8

這是很好的和容易(其他的答案沒有工作對我來說),發現here

ImageView iv = (ImageView) findViewById(R.id.imageView); 
    Bitmap bMap = BitmapFactory.decodeResource(getResources(), R.drawable.picture); 
    Bitmap bMapScaled = Bitmap.createScaledBitmap(bMap, newWidth, newHeight, true); 
    iv.setImageBitmap(bMapScaled); 

Android文檔可here

0

後加載您的圖片,並將其設置爲imageview的 你可以使用layoutparamsto大小的圖像match_parent

這樣

android.view.ViewGroup.LayoutParams layoutParams = imageView.getLayoutParams(); 
layoutParams.width =MATCH_PARENT; 
layoutParams.height =MATCH_PARENT; 
imageView.setLayoutParams(layoutParams); 
相關問題