Steps to be followed for conditional formatting:
1. Open Allitems.aspx page of the respective list from SharePoint designer.
2. Right click on list view web part and click convert to xslt data view.
3. You need to add one temporary record before applying conditional formatting.
4. After that select any row Right click and click on conditional formatting.
5. In the window opened for conditional formatting click on Create a Apply formatting (As shown in figure below)
6. One window will appear for giving condition. Click on new clause
And give the condition as per shown in the image below and then click on ok.
7. There will appear a new window asking for modify styles give the styles as per the requirement e.g.
And Click Ok
8. Let the row remain selected again go to create in conditional formatting window follow same procedure listed above in points[5-7] . Give the condition as Task status Equal Completed and select background colour as green/ Task status equal Inprogress and Due date is less than current date select colour as red etc.
9. Save the page and check with browser.
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