Android 使alertDialog.builder不会点击外面和按返回键消失

    public void showNoProject(){
        Builder builder = new AlertDialog.Builder(MainActivity.this)
        .setMessage("您还没有项目，请先添加项目")
        .setPositiveButton("去添加项目", new OnClickListener() {
            
            @Override
            public void onClick(DialogInterface dialog, int which) {
                dialog.dismiss();
                
            }
        })
        .setNegativeButton("关闭", new OnClickListener() {
            
            @Override
            public void onClick(DialogInterface dialog, int which) {
                dialog.dismiss();
                
            }
        });
        builder.setCancelable(false);
        builder.show();
    }