> For the complete documentation index, see [llms.txt](https://docs.thunkable.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.thunkable.com/~/changes/wHhkjLVeheBnfbpghRnw/stack-navigator.md).
# Stack Navigator
## Stack Navigator Properties
### Set Your Screen Transitions
To enable a Stack transition, you will have to add a Screen navigation block like the one below. You can find the Screen navigation block in the pre-built Control category:
Screens can Stack from left to right or from top to bottom. You can set the transition style with the Stack property below:
| Property | Description | Data Type |
| -------- | ----------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------- |
| Mode | Define how your screens will stack. | Select from list:
card - stacks screens from left to right
modal - stacks screens from top to bottom
|
{% hint style="warning" %}
It is not possible to use blocks to navigate from a screen **outside** of your Stack Navigator to a screen **inside** your Stack Navigator
{% endhint %}
### Hide Your Header
It is possible to hide the Header bar and maintain the Stacking transition by using the Stack property below. Hiding the Header bar will also hide the back button that makes it easier to transition to your original screen
| Property | Description | Data Type |
| ---------- | ------------------------------------------ | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| HeaderMode | Define how the header appears in your app. | Select from list:
float - header floats at the top of the screen and the app content scrolls underneath the header
screen - header scrolls with the page
none - hide header
|
---
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