android,点击返回按钮回到主菜单

只需在你当前的activity的Java文件中重写onKeyDown方法

@Override
    public boolean onKeyDown(int keyCode, KeyEvent event)
    {
        if(keyCode == KeyEvent.KEYCODE_BACK){
            Intent myIntent = new Intent();
            myIntent = new Intent(当前Activity的名称.this, 主页面Activity.class);
            startActivity(myIntent);
            this.finish();
        }
        return super.onKeyDown(keyCode, event);
    }