Bug report #18770
[Layout] Using an item variable to change its own properties dynamically does not work
| Status: | Open | ||
|---|---|---|---|
| Priority: | Normal | ||
| Assignee: | - | ||
| Category: | Map Composer/Printing | ||
| Affected QGIS version: | 3.5(master) | Regression?: | No |
| Operating System: | Easy fix?: | No | |
| Pull Request or Patch supplied: | No | Resolution: | |
| Crashes QGIS or corrupts data: | No | Copied to github as #: | 26657 |
Description
Let's add a map item and try to change its position using data-defined properties.
If I write expression like case when @layout_pageheight >210 then 10 else 40 end for the X position data-defined button, then anytime i change the page size crossing the 210, I can see the map item moving in the layout. Great!
Now if i write case when @map_scale >5000 then 10 else 40 end for the same property and change the scale of the map item, it does not move... until something else triggers its displacement ie:
- I use the select/move item button to move the item
- I manually change the X position spinbox value
- or I have another call (let's say the one with layout_pageheight) that triggers a movement
In all these case, it will move to the data-defined position.
I checked with other internal variable of the map item (map_rotation, eg) and other items (eg, label item with its rotation data-defined button using item_id variable) and anytime I use an interval variable to set a property of the item, no change occurs dynamically.
This makes the layout item's variables a bit useless (as you can not even call them from another item properties in 2.18).
Affects both 2.18 and 3.1 (master)
History
#1
Updated by Nyall Dawson about 6 years ago
Other actions trigger a refresh too - e.g. clicking refresh, changing to a new atlas feature, exporting the layout.
#2
Updated by Harrissou Santanna about 6 years ago
I could have bet that I tried the refresh button unsuccessfully but i'd have lost... So yes, my list was not complete.
Anyway, good to see that when output time comes, the expressions are applied.
#3
Updated by Jürgen Fischer over 5 years ago
- Status changed from Open to Feedback
Please test with QGIS 3.4 - QGIS 2.18 reached it's end of life.
#4
Updated by Harrissou Santanna over 5 years ago
- Affected QGIS version changed from 2.18.18 to 3.5(master)
- Status changed from Feedback to Open
Confirmed on master 3.5. Using @map_scale does not visually trigger the map item placement in my example; you may need to eg refresh the dialog beforehand.