Difference between revisions of "Win32/64 Interface"
| Line 3: | Line 3: | ||
The scrolling is currently done by moving the childs instead of the client area as the LCL expects. For example in some cases it looks as if the childs are scrolled in reverse direction. The truth is that the scrolling is pretty much broken. Scrolling the childs is incompatible to the other widgetsets and has a drawback: Moving one child after the other generates several move messages. The LCL receives the messages and each time it has to react. For example it has to realign all anchored childs. You can control this trouble for one widgetset but it will never work well for all. So this works for Delphi VCL, but not for the LCL. Therefore another approach must be implemented: | The scrolling is currently done by moving the childs instead of the client area as the LCL expects. For example in some cases it looks as if the childs are scrolled in reverse direction. The truth is that the scrolling is pretty much broken. Scrolling the childs is incompatible to the other widgetsets and has a drawback: Moving one child after the other generates several move messages. The LCL receives the messages and each time it has to react. For example it has to realign all anchored childs. You can control this trouble for one widgetset but it will never work well for all. So this works for Delphi VCL, but not for the LCL. Therefore another approach must be implemented: | ||
| + | ===Solution=== | ||
Between child windows and parent window a 'client area' window will be inserted. The child windows are put onto the 'client area' window and when the childs are scrolled the 'client area' window is moved instead. This is already done by the other widgetsets. | Between child windows and parent window a 'client area' window will be inserted. The child windows are put onto the 'client area' window and when the childs are scrolled the 'client area' window is moved instead. This is already done by the other widgetsets. | ||
Mattias: I will implement this eventually, but my winapi interface knowledge is little and I have a lot of other lazarus tasks already, so I can't say when I implement it. | Mattias: I will implement this eventually, but my winapi interface knowledge is little and I have a lot of other lazarus tasks already, so I can't say when I implement it. | ||
Revision as of 19:53, 30 January 2008
Scrolling
The scrolling is currently done by moving the childs instead of the client area as the LCL expects. For example in some cases it looks as if the childs are scrolled in reverse direction. The truth is that the scrolling is pretty much broken. Scrolling the childs is incompatible to the other widgetsets and has a drawback: Moving one child after the other generates several move messages. The LCL receives the messages and each time it has to react. For example it has to realign all anchored childs. You can control this trouble for one widgetset but it will never work well for all. So this works for Delphi VCL, but not for the LCL. Therefore another approach must be implemented:
Solution
Between child windows and parent window a 'client area' window will be inserted. The child windows are put onto the 'client area' window and when the childs are scrolled the 'client area' window is moved instead. This is already done by the other widgetsets.
Mattias: I will implement this eventually, but my winapi interface knowledge is little and I have a lot of other lazarus tasks already, so I can't say when I implement it.
