#UITree

This page documents the UITree CDP domain supported by Lynx DevTool.

#Overview

• Scope: instance
• CDP domain: Lynx-specific

#Lynx Extensions

#UITree.disable

Disables Lynx UI tree inspection methods on the current target.

• Origin: lynx-extension
• Source: devtool/lynx_devtool/agent/domain_agent/inspector_ui_tree_agent.cc

#Parameters

No parameters.

#Returns

No return fields.

#Notes

• Dispatches through LynxDevToolMediator to InspectorUIExecutor on the UI thread.
• Clears the UI tree enabled flag used by UITree.getLynxUITree, UITree.getUIInfoForNode, and UITree.setUIStyle.
• Returns an empty result object.
• The native implementation does not read request params.
• If the mediator has no UI task runner, the current handler does not send an explicit CDP response.

#Examples

Disable UI tree inspection

Request:

{
  "id": 1,
  "method": "UITree.disable"
}

Response:

{
  "id": 1,
  "result": {}
}

#UITree.enable

Enables Lynx UI tree inspection methods on the current target.

• Origin: lynx-extension
• Source: devtool/lynx_devtool/agent/domain_agent/inspector_ui_tree_agent.cc

#Parameters

#Returns

No return fields.

#Notes

• Dispatches through LynxDevToolMediator to InspectorUIExecutor on the UI thread.
• Sets the UI tree enabled flag used by UITree.getLynxUITree, UITree.getUIInfoForNode, and UITree.setUIStyle.
• Returns an empty result object.
• The default compression threshold before this method changes it is 10240 bytes.
• If the mediator has no UI task runner, the current handler does not send an explicit CDP response.

#Examples

Enable UI tree inspection

Request:

{
  "id": 1,
  "method": "UITree.enable",
  "params": {
    "useCompression": true,
    "compressionThreshold": true
  }
}

Response:

{
  "id": 1,
  "result": {}
}

#UITree.getLynxUITree

Returns the platform Lynx UI tree for the current page.

• Origin: lynx-extension
• Source: devtool/lynx_devtool/agent/domain_agent/inspector_ui_tree_agent.cc

#Parameters

No parameters.

#Returns

#Notes

• Requires UITree.enable first. If UI tree inspection is not enabled, the current handler returns without sending a CDP response.
• Dispatches through LynxDevToolMediator to InspectorUIExecutor on the UI thread.
• The platform facade returns a JSON string, and the executor parses that string into result.root.
• Android and Darwin include name, id, tagName, nodeIndex, props, label, frame, and children. Harmony includes name, id, frame, and children.
• If compression is enabled and the serialized root exceeds the stored threshold, result.compress is true and result.root is a compressed base64 string.
• The native implementation does not read request params.
• If the mediator has no UI task runner or the platform facade is unavailable, the current handler does not send an explicit CDP response.

#Examples

Read the Lynx UI tree

Request:

{
  "id": 1,
  "method": "UITree.getLynxUITree"
}

Response:

{
  "id": 1,
  "result": {
    "compress": false,
    "root": {
      "name": "com.lynx.tasm.behavior.ui.view.UIView",
      "id": 1,
      "tagName": "view",
      "nodeIndex": 0,
      "props": {},
      "label": "",
      "frame": [0, 0, 390, 844],
      "children": []
    }
  }
}

#UITree.getUIInfoForNode

Returns detailed platform UI information for one Lynx UI node.

• Origin: lynx-extension
• Source: devtool/lynx_devtool/agent/domain_agent/inspector_ui_tree_agent.cc

#Parameters

#Returns

#Notes

• Requires UITree.enable first. If UI tree inspection is not enabled, the current handler returns without sending a CDP response.
• Dispatches through LynxDevToolMediator to InspectorUIExecutor on the UI thread.
• The platform facade returns a JSON string, and the executor parses that string directly into result.
• If the platform returns an empty string or the node id cannot be resolved, the current handler returns an empty result object.
• Android, Darwin, and Harmony expose different platform-owned details. Consumers should tolerate missing optional fields.
• If the mediator has no UI task runner or the platform facade is unavailable, the current handler does not send an explicit CDP response.

#Examples

Read UI information for one node

Request:

{
  "id": 1,
  "method": "UITree.getUIInfoForNode",
  "params": {
    "UINodeId": 42
  }
}

Response:

{
  "id": 1,
  "result": {
    "id": 42,
    "editableProps": {
      "border": [0, 0, 0, 0],
      "margin": [0, 0, 0, 0],
      "frame": [0, 0, 100, 50],
      "visible": true
    },
    "ui": {
      "name": "com.lynx.tasm.behavior.ui.view.UIView",
      "readonlyProps": {}
    },
    "view": {
      "name": "android.view.View",
      "readonlyProps": {}
    }
  }
}

#UITree.setUIStyle

Applies an editable style value to a Lynx UI node through the platform helper.

• Origin: lynx-extension
• Source: devtool/lynx_devtool/agent/domain_agent/inspector_ui_tree_agent.cc

#Parameters

#Returns

#Notes

• Requires UITree.enable first. If UI tree inspection is not enabled, the current handler returns without sending a CDP response.
• Dispatches through LynxDevToolMediator to InspectorUIExecutor on the UI thread.
• The handler forwards params.UINodeId, params.styleName, and params.styleContent to DevToolPlatformFacade::SetUIStyle.
• The response is an empty result object when the platform return value is not -1.
• When the platform return value is -1, the response still uses result.error rather than a top-level CDP error.
• Android, Darwin, and Harmony support frame, margin, border, visible, background-color, and border-color, but unsupported or invalid inputs do not produce identical platform return values.
• If the mediator has no UI task runner or the platform facade is unavailable, the current handler does not send an explicit CDP response.

#Examples

Update a UI frame

Request:

{
  "id": 1,
  "method": "UITree.setUIStyle",
  "params": {
    "UINodeId": 42,
    "styleName": "frame",
    "styleContent": "0,0,100,50"
  }
}

Response:

{
  "id": 1,
  "result": {}
}

Failed style update

Request:

{
  "id": 2,
  "method": "UITree.setUIStyle",
  "params": {
    "UINodeId": 42,
    "styleName": "frame",
    "styleContent": "invalid"
  }
}

Response:

{
  "id": 2,
  "result": {
    "error": {
      "code": -32000,
      "message": "set ui style fail"
    }
  }
}