Qt Quick 2 Inspector

Overview

The Qt Quick 2 inspector is the tool of choice for investigating issues with a Qt Quick user interface. This includes:

  • Inspecting the visual item hierarchy.
  • Remote view of the rendered content with diagnostic overlays.
  • Inspecting the scene graph used for rendering the user interface on the GPU.

If your target has multiple QQuickView instances, the combo box at the top can be used to switch between them.

Item Tree

The item tree is shown on the top left, and it contains the visual hierarchy of QQuickItem instances in the currently selected Qt Quick scene. This does not necessarily match the QObject parent/child hierarchy. The right side contains the same property view for the selected item you already know from the Object Inspector.

You can navigate to the object inspector (and other applicable tools) using the context menu on the item tree. Similarly, you can navigate to the source code locations instantiating the current item, or the file declaring the type of the current item (if available).

Remote View

The remote view is shown to the lower left in the Qt Quick 2 inspector. Besides giving you a zoomable view of the rendered content, it provides a number of additional features:

  • Element picking.
  • Diagnostic overlays with layout information.
  • Input event forwarding, for working with embedded targets.
  • A measurement tool.
  • Enabling of diagnostic render modes on target (availability depends on Qt version).

Paint Analyzer

When selecting a QQuickPaintedItem sub-class in the item tree, the paint analyzer tab is activated in the property view on the right.

The paint analyzer allows you to inspect every single QPainter command that is executed, and look at the visual result after each step.

Scene Graph

The scene graph view shows you the internal representation used by Qt Quick 2 to render the current scene. This is particularly useful for debugging performance issues related to batching and rendering of custom QQuickItem sub-classes.

For nodes in the scene graph you have access to:

  • QSGNode properties, in particularly node flags and transformation matrices.
  • Shader code, if the node has a material associated with it.
  • Geometry and other per-vertex data, when looking at a geometry node.

Examples

The following examples make use of the Qt Quick inspector:

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