Dynamic visibility of Gallery Items based on previous item data in Canvas PowerApps
Introduction
Let’s say you come across a scenario where you want to show dynamic records for your gallery items based on previous record details.
For example: Let’s say a basic Q&A where the User should input data and then proceed.
So, I have created something similar that will help in developing such a design quickly and efficiently.
Steps to implement in Canvas PowerApps
Step 1: Create a collection that will store data of the gallery. (You can use Dataverse records here with the unique identifier in the collection.)
Note: Collection is better to use if you are referring to the same table. If you use Gallery.AllItems then you will encounter errors and circular reference issues.
//A Button to execute a collection of records. (You can trigger onLoad of screen as well)
ClearCollect(
    colAnswers,
    {
        ID: 1,
        Question: "This is 1st Question (always visible)",
        isVisible: true
    },
    {
        ID: 2,
        Question: "This is 2nd Question",
        isVisible: false
    },
    {
        ID: 3,
        Question: "This is 3rd Question",
        isVisible: false
    },
    {
        ID: 4,
        Question: "This is 4th Question",
        isVisible: false
    }
)Set a Blank Vertical Gallery where Items property is as follows:
//Items property on Gallery
Filter(colAnswers,isVisible = true)Step 2: Add a Text Input in Gallery that will accept the User’s Input Along with Questions.

//OnChange of Text-Input
If(
    IsBlank(TxtAnswer.Text),
    UpdateIf(
        colAnswers,
        ID > ThisItem.ID,
        {
            isVisible: !IsBlank(TxtAnswer.Text)
        }
    ),
    UpdateIf(
        colAnswers,
        ID = ThisItem.ID + 1,
        {
            isVisible: !IsBlank(TxtAnswer.Text)
        }
    )
)Conclusion
That’s all. You got dynamic content based on previous values. 
I hope this helps!
 
								 
								