使用布局膨胀器将外部 XML 布局转换为位图

Question

所以我有以下布局称为demo_text.xml

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/screen">
<TextView
android:id="@+id/textToDisplay"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:text="Hello World"
</FrameLayout>

我正在尝试将此demo_text转换为位图。这是我的onCreate：

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
View inflatedFrame = getLayoutInflater().inflate(R.layout.demo_text, null);
FrameLayout frameLayout = (FrameLayout) inflatedFrame.findViewById(R.id.screen) ;
frameLayout.setDrawingCacheEnabled(true);
frameLayout.buildDrawingCache();
Bitmap bm = frameLayout.getDrawingCache();
}

我希望位图是整个布局，但位图总是返回 null。

Answer 1

以下代码有效：

View inflatedFrame = getLayoutInflater().inflate(R.layout.demo_text, null);
FrameLayout frameLayout = (FrameLayout) inflatedFrame.findViewById(R.id.screen) ;
frameLayout.setDrawingCacheEnabled(true);
frameLayout.measure(View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED),
View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED));
frameLayout.layout(0, 0, frameLayout.getMeasuredWidth(), frameLayout.getMeasuredHeight());
frameLayout.buildDrawingCache(true);
final Bitmap bm = frameLayout.getDrawingCache();

Answer 2

你可以试试下面的代码

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
FrameLayout frameLayout = (FrameLayout) inflatedFrame.findViewById(R.id.screen);  
Bitmap b  = loadBitmapFromView(frameLayout);
}

使用 Belolw 方法获取位图。

public  Bitmap loadBitmapFromView(View v) {
Bitmap b = Bitmap.createBitmap( v.getLayoutParams().width, 
v.getLayoutParams().height, Bitmap.Config.ARGB_8888);                
Canvas c = new Canvas(b);
v.layout(v.getLeft(), v.getTop(), v.getRight(), v.getBottom());
v.draw(c);
return b;
}