SystemWindow的初始位置（Cuis Smalltalk）

Question

我已經做了一個子類＃Mosaic1的#SystemWindow，我想控制窗口的初始位置。我怎麼做？類#RealEstateAgent涉及但如何？班級評論說

Responsible for real-estate management on the screen, 
which is to say, controlling where new windows appear, 
with what sizes, etc. 5/20/96 sw 

所以我要求解釋如何配置和使用類#RealEstateAgent。

注：

• #RealEstateAgent是一個單。它只有類端方法
• 它僅由#SystemWindow
• 新SystemWindow從RealEstateAgent類獲取其初始程度引用>> standardWindowExtent

Answer 1

一種解決方案是繞過類＃ RealEstateAgent並編寫自己的代碼來處理SystemWindow的新實例的初始大小和位置。

這可以通過重寫SystemWindow >> openInWorld完成：程度：

openInWorld: aWorld extent: extent 
"This msg and its callees result in the window being activeOnlyOnTop" 
aWorld addMorph: self. 

self morphPosition: 
     (RealEstateAgent initialFrameFor: self world: aWorld) topLeft; 
     morphExtent: extent. 

aWorld startSteppingSubmorphsOf: self. 


"Do it deferred. Was needed for text cursor to start blinking 
    if (Preferences disable: #focusFollowsMouse) " 

WorldState addDeferredUIMessage: [ self activate ] 

替換

self morphPosition: 
     (RealEstateAgent initialFrameFor: self world: aWorld) topLeft; 
     morphExtent: extent. 

計算

• thePositionOfTheWindow
• theExtentOfTheWindow

然後做

self morphPosition: thePositionOfTheWindow morphExtent: theExtentOfTheWindow.