Android BitmapFactory.decodeResource() 为 xml drawable 中定义的形状返回 null
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BitmapFactory.decodeResource() returns null for shape defined in xml drawable
提问by mol
I looked through multiple similar questions, although I haven't found proper answer on my query.
我浏览了多个类似的问题，但我的查询没有找到正确的答案。
I have a drawable, defined in shape.xml
我有一个 drawable，在 shape.xml 中定义
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="rectangle" >
<solid android:color="@color/bg_color" />
</shape>
I want to convert it to Bitmap object in order to perform some operations, but BitmapFactory.decodeResource()returns null.
我想将其转换为 Bitmap 对象以执行某些操作，但BitmapFactory.decodeResource()返回 null。
This is how I'm doing it:
这就是我的做法：
Bitmap bmp = BitmapFactory.decodeResource(getResources(), R.drawable.shape);
What am I doing wrong? Is BitmapFactory.decodeResource()applicable for xml defined drawables?
我究竟做错了什么？是BitmapFactory.decodeResource()适用于XML定义可绘制？
回答by Philipp Jahoda
Since you want to load a Drawable, not a Bitmap, use this:
由于您要加载 a Drawable，而不是 a Bitmap，请使用以下命令：
Drawable d = getResources().getDrawable(R.drawable.your_drawable, your_app_theme);
To turn it into a Bitmap:
把它变成一个Bitmap：
public static Bitmap drawableToBitmap (Drawable drawable) {
if (drawable instanceof BitmapDrawable) {
return ((BitmapDrawable)drawable).getBitmap();
}
Bitmap bitmap = Bitmap.createBitmap(drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight(), Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);
drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());
drawable.draw(canvas);
return bitmap;
}
Taken from: How to convert a Drawable to a Bitmap?
回答by Ali Bagheri
public static Bitmap convertDrawableResToBitmap(@DrawableRes int drawableId, Integer width, Integer height) {
Drawable d = getResources().getDrawable(drawableId);
if (d instanceof BitmapDrawable) {
return ((BitmapDrawable) d).getBitmap();
}
if (d instanceof GradientDrawable) {
GradientDrawable g = (GradientDrawable) d;
int w = d.getIntrinsicWidth() > 0 ? d.getIntrinsicWidth() : width;
int h = d.getIntrinsicHeight() > 0 ? d.getIntrinsicHeight() : height;
Bitmap bitmap = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);
g.setBounds(0, 0, w, h);
g.setStroke(1, Color.BLACK);
g.setFilterBitmap(true);
g.draw(canvas);
return bitmap;
}
Bitmap bit = BitmapFactory.decodeResource(getResources(), drawableId);
return bit.copy(Bitmap.Config.ARGB_8888, true);
}
//------------------------
Bitmap b = convertDrawableResToBitmap(R.drawable.myDraw , 50, 50);
回答by Raindeavor
You may have put .xmlinto directory:.../drawable-24, and try to put it into .../drawableinstead.
您可能已放入.xmldirectory:... /drawable-24，并尝试将其放入 ... /drawable。
it works for me, hope this can help someone.
它对我有用，希望这可以帮助某人。
回答by Blackbelt
it is a drawable, not a bitmap. You should use getDrawableinstead
它是可绘制的，而不是位图。你应该getDrawable改用
