java - 为什么gradientdrawable.setBackground会让我的应用程序崩溃？

Question

public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {


        GradientDrawable drawable = new GradientDrawable();
        drawable.setShape(GradientDrawable.RECTANGLE);
        drawable.setStroke(3, Color.GREEN);

        View view = inflater.inflate(R.layout.primary, container, false);
        LinearLayout layout = (LinearLayout ) view.findViewById(R.layout.primary);
        // 1 layout.setBackground(fragmentBorder); <----
                // ^ above line causes the crash ^

        layout.setBackgroundDrawable(drawable); 
        return view; 
    }

没有编译错误，只是在测试时崩溃了

Answer 1

LinearLayout layout = (LinearLayout ) view.findViewById(R.layout.primary);

请将上面的行更改为

 LinearLayout layout = (LinearLayout ) view.findViewById(R.id.primary);

你的线性布局仍然为空，这就是它崩溃的原因