用黑色保留區域問題創建新的位圖

Question

我必須從用原始圖像創建新的位圖後用戶做一些事情，像放大，旋轉，拖動。我有一個框架邊框，只有部分原始圖像躺在框架上被挑選出來。問題是幀的剩餘區域是黑色的，我希望它可以是透明或白色的。怎麼做？提前致謝。

public Bitmap createBitmap(final Matrix pMatrix, final Bitmap pSourceBitmap){ 

    Bitmap bmp = Bitmap.createBitmap(width, height, pSourceBitmap.getConfig()); 

Canvas canvas = new Canvas(bmp); 
    canvas.drawBitmap(pSourceBitmap, pMatrix, new Paint()); 

    return bmp; 
} 

Answer 1

爲了使剩餘部分透明

使用下面的代碼

public Bitmap createBitmap(final Matrix pMatrix, final Bitmap pSourceBitmap) 
{ 
    Bitmap.Config conf = Bitmap.Config.ARGB_8888; 
    Bitmap bmp= Bitmap.createBitmap(width, height, conf); 
    Canvas canvas = new Canvas(bmp); 
    canvas.drawBitmap(pSourceBitmap, pMatrix, new Paint()); 

    return bmp; 
}