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# DisplayHandler (interface)
Implement this interface to handle events related to browser display
state. The methods of this class will be called on the UI thread.
Table of contents:
* [Callbacks](#callbacks)
* [OnAddressChange](#onaddresschange)
* [OnAutoResize](#onautoresize)
* [OnConsoleMessage](#onconsolemessage)
* [OnLoadingProgressChange](#onloadingprogresschange)
* [OnStatusMessage](#onstatusmessage)
* [OnTitleChange](#ontitlechange)
* [OnTooltip](#ontooltip)
## Callbacks
### OnAddressChange
| Parameter | Type |
| --- | --- |
| browser | [Browser](Browser.md) |
| frame | [Frame](Frame.md) |
| url | string |
| __Return__ | void |
Called when a frame's address has changed.
### OnAutoResize
| Parameter | Type |
| --- | --- |
| browser | [Browser](Browser.md) |
| new_size | list[width, height] |
| __Return__ | bool |
Description from upstream CEF:
> Called when auto-resize is enabled via CefBrowserHost::SetAutoResizeEnabled
> and the contents have auto-resized. |new_size| will be the desired size in
> view coordinates. Return true if the resize was handled or false for
> default handling.
### OnConsoleMessage
| Parameter | Type |
| --- | --- |
| browser | [Browser](Browser.md) |
| level | int |
| message | string |
| source | string |
| line | int |
| __Return__ | bool |
Called to display a console message. Return true to stop the message from
being output to the console.
|level| can be one of the same values as in ApplicationSettings.[log_severity](ApplicationSettings.md#log_severity).
### OnLoadingProgressChange
| Parameter | Type |
| --- | --- |
| browser | [Browser](Browser.md) |
| progress | double |
| __Return__ | void |
Description from upstream CEF:
> Called when the overall page loading progress has changed. |progress|
> ranges from 0.0 to 1.0.
### OnStatusMessage
| Parameter | Type |
| --- | --- |
| browser | [Browser](Browser.md) |
| value | string |
| __Return__ | void |
Called when the browser receives a status message.
### OnTitleChange
| Parameter | Type |
| --- | --- |
| browser | [Browser](Browser.md) |
| title | string |
| __Return__ | void |
Called when the page title changes.
### OnTooltip
| Parameter | Type |
| --- | --- |
| browser | [Browser](Browser.md) |
| text_out | list |
| __Return__ | bool |
Called when the browser is about to display a tooltip. `text_out[0]` contains the
text that will be displayed in the tooltip. To handle the display of the
tooltip yourself return true. Otherwise, you can optionally modify `text_out[0]`
and then return false to allow the browser to display the tooltip.
When window rendering is disabled the application is responsible for
drawing tooltips and the return value is ignored.