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最新版Qt 6.3已正式发布。 了解更多。
最新バージョンQt6.5がご利用いただけます。 詳細はこちら

# Gradients

Canvas can fill shapes with color but also with gradients or images.

onPaint: {
    var ctx = getContext("2d")

    var gradient = ctx.createLinearGradient(100,0,100,200)
    gradient.addColorStop(0, "blue")
    gradient.addColorStop(0.5, "lightsteelblue")
    ctx.fillStyle = gradient

The gradient in this example is defined along the starting point (100,0) to the end point (100,200), which gives a vertical line in the middle of our canvas. The gradient-stops can be defined as a color from 0.0 (gradient start point) to 1.0 (gradient endpoint). Here we use a blue color at 0.0 (100,0) and a lightsteelblue color at the 0.5 (100,200) position. The gradient is defined as much larger than the rectangle we want to draw, so the rectangle clips gradient to it’s defined the geometry.



The gradient is defined in canvas coordinates not in coordinates relative to the path to be painted. A canvas does not have the concept of relative coordinates, as we are used to by now from QML.