Android的 - 位圖轉換從SD卡

Question

到繪製

嘿有一些奇怪的顯示出來，當我將位圖轉換從SD卡的可繪製至於調整：

String sdDir = Environment.getExternalStorageDirectory().getPath(); 
String filename = "test.png"; //420px X 420px 
Drawable tmpDraw; 
Bitmap tmpBit = BitmapFactory.decodeFile(sdDir+filename); 

Log.e("BAH","Bitmap height:"+tmpBit.getHeight()); //420 

tmpDraw = (Drawable) new BitmapDrawable(getResources(),tmpBit); 
int height = tmpDraw.getMinimumHeight(); 

Log.e("BAH","Drawable height:"+height); //420 

我假設我需要一個參照點從縮放？如果從SDCard讀取一個文件，它被歸類爲MDPI，這就是它被重新調整的原因？我目前正在使用Nexus 7來測試哪種TVDPI。我希望縮放發生，就好像位圖是在HDPI中一樣。

任何建議將不勝感激！

想我已經破解了：

String sdDir = Environment.getExternalStorageDirectory().getPath(); 
String filename = "test.png"; //420px X 420px 
Drawable tmpDraw; 

BitmapFactory.Options options = new BitmapFactory.Options(); 
DisplayMetrics metrics = getApplicationContext().getResources().getDisplayMetrics(); 
options.inDensity = 240; //Being DPI for HDPI 
options.inTargetDensity=metrics.densityDpi; //Being current DPI 
//inDensity/inTargetDensity are a ratio 

Bitmap tmpBit = BitmapFactory.decodeFile(sdDir+filename,options); 

Log.e("BAH","Bitmap height:"+tmpBit.getHeight()); //373 Correct for TVDPI 

tmpDraw = (Drawable) new BitmapDrawable(getResources(),tmpBit); 
int height = tmpDraw.getMinimumHeight(); 

Log.e("BAH","Drawable height:"+height); //373 Correct for TVDPI 

這是做一個可以接受的方式？

Answer 1

是的，你應該通過一個Resources到BitmapDrawable構造函數，所以它不會搞砸了。