Java JFrame菜单隐藏

Java JFrame菜单隐藏,java,swing,Java,Swing,在JFrame菜单中添加画布时,为什么我的菜单总是隐藏在画布后面 canvas = new MyCanvas(); canvas.setBackground(Color.lightGray); contain.add(canvas, BorderLayout.CENTER); 将画布添加到contentpane中 this.getContentPane().add(canvas,BorderLayout.CENTER);

在JFrame菜单中添加画布时,为什么我的菜单总是隐藏在画布后面

    canvas = new MyCanvas();
    canvas.setBackground(Color.lightGray);

    contain.add(canvas, BorderLayout.CENTER);

将画布添加到contentpane中

this.getContentPane().add(canvas,BorderLayout.CENTER);