TOUCHGFX CANVAS WIDGET (划线)

1.draw line （参考例程  touchgfx demo1）

      demo1  实现了多种线条的绘制

     实现的文件为

 

void Screen1View::setupScreen()
{
 //   Screen1ViewBase::setupScreen();

	//Screen1ViewBase::setupScreen();

	// Place the graph on the screen
	graph.setXY(20, 20);

	// Set the outer dimensions and color of the graph
	graph.setup(440, 200, Color::getColorFrom24BitRGB(0xFF, 0, 0));

	// Set the range for the x and y axis of the graph. That is
	// the max and min x/y value that can be displayed inside the
	// dimension of the graph.
	graph.setRange(0, 50, 0, 200);

	// Set the line width in pixels
	graph.setLineWidth(3);

	add(graph);


}

 

void Screen1View::handleTickEvent()
{
	// Number of ticks between inserting a point in the graph
	int interval = 5;

	tickCounter++;

	if (tickCounter % interval == 0)
	{
		// Insert a point in the graph.
		// The Y value is a random number in the y range of the graph.
		graph.addValue(tickCounter / interval, tickCounter);  // randomNumberBetween(graph.getRangeBottom(), graph.getRangeTop()
	}

	if (tickCounter == 37 * interval)
	{
		// Change the range of the Y axis
	//	graph.setRange(0, 50, 0, 400);
	//	graph.invalidate();
	}

	if (tickCounter == 50 * interval)
	{
		// Reset the graph and start over
	//	graph.setRange(0, 50, 0, 200);
	//	graph.setLineWidth(2);
	//	graph.clear();
	//	graph.invalidate();

	//	tickCounter = 0;
	}
}

执行的界面图：