How Android animates curves

There is a similar article in the Lecheng Mobile Developers Alliance.

To draw a curve diagram, you first need to draw the horizontal and vertical coordinate axes to establish the coordinate system, for example, how long the 100 distance in the coordinate system should be drawn in the canvas, this needs to be calculated, in fact, the establishment of the coordinate system is the most complex, I have seen many third-party libraries The establishment methods are different, some are more flexible, and some are more rigid. As for drawing curves, either by method or by method, it depends on your own habits.

In order to make a good-looking graph, I referred to two open sources**, the first one has more restrictions on drawing the graph, and the scope of use is too narrow, but there is an animation effect when the data changes. The second one has a wide range of applications, he can automatically calculate the number of horizontal and vertical coordinates according to the data set, the distance of cells on the canvas, just enter the coordinate points to automatically establish the coordinate system and draw curves, but there is no animation effect.

Let's start with the first lineview.

The demo of lineview can be here**,Lineview is actually just a part of the github project.,I extracted it.,Personally, I don't think the other parts of it have reference value.。 The author seems to be a Korean.

There is nothing desirable about LineView's curve drawing, what I want to learn is his method of achieving animation effects, which is well designed, but the specific implementation needs to be improved to make the animation smoother.

LineView:

Add a LineView control in the XML.

mpandroidchart

Powerful charting tools, support line charts, area charts, scatter charts, time charts, bar charts, pie charts, bubble charts, donut charts, range (high to low) bar charts, network charts and a combination of various charts; Support drag and drop zoom of graphs; Support Android and above, support horizontal and vertical axis zoom, multi-finger zoom, display animation, highlight, save to SDCARD, read charts from files.

achartengine

Powerful charting tools that support line charts, area charts, scatter charts, time charts, bar charts, pie charts, bubble charts, donut charts, range (high to low) bar charts, dial charts, cube charts, and a combination of various graphs.

graphview

Draw charts and curve charts in view, which can be used to display curved charts, bar charts, and wave charts on Android.

holographlibrary

Draw line charts, bar charts, pie charts.

xcl-charts

xcl-charts is based on the native canvas to draw various charts, and when designing, try to ensure the development efficiency while providing users with enough customization capabilities. This makes it easy to use and has a fairly flexible customization capability. Currently, 3D non-3D bar charts are supported. Gauge chart), radar chart, circle chart, etc.

Other features include support for chart zoom, gesture movement, animation display effects, high-density column display, chart demarcation custom lines, hybrid display of multiple charts, and switching between different types of charts from the same data source.

eazegraph

Android charting library, support for bar charts, hierarchical bar charts, pie charts, linear charts.

williamchart

The chart drawing library supports three chart types: LineChartView, BarChartView, and StackBarchartView, and supports Android and above systems.

hellocharts for android

Support line charts, bar charts, pie charts, bubble charts, and combination charts; Support preview, zoom in, scrolling, and some charts support animation; Support Android and above.

Get the lineview object in activity:

finallineview lineview = (lineview)findviewbyid(;

Add abscissa:

int randomint = 9;

arraylisttest =newarraylist();

for (int i=0;idatalist = newarraylist();

intrandom = (int)(;

for (int i=0;i>datalists = newarraylist>()

As can be seen from its usage, lineview needs to set the range of abscissa in advance, and the value of the ordinate must correspond to the value added one-to-one (read the lineview source code to know), it is very inconvenient to use, I think the author just made a curve, and did not pay much attention to whether it was useful. Like many open source graphs, LineView allows you to draw several curves of different colors at once.

Just add another list member to the datalists in the ** above.

I'm using androidchart.,Draw **** pictures or something.,All kinds of charts can be.,I see there's no problem with you.,This project is open source.。

Go to the Android Bus There are related cases above.

With fusionchartsjs, I tested it myself, and there was no problem.

There is an open-source library chartview, which is available after searching on the Internet.