Updating a chart from an ArrayList over time?

Question

I have an ArrayList of values, and I would like to iterate through the ArrayList. For every new value, I would like to update the chart with that value, and then wait a set amou

Answer 1

If your addEntry() performs a UI operation then let me explain your problem -

Explanation -

Android is an event based system. Something happens on the device (the screen is touched, a key is pressed, etc.) and Android raises an event. An App is notified of an event and when one occurs that it needs to respond to it does so, often running the code that you have written. Your App runs its code in a loop under the control of the Android Operating Systems (OS). This code loop is referred to as the App's thread of execution. There is only one thread and it is responsible for both running the App code and updating the display.

So the UI update does not happen immediately and your making the UI thread sleep for 100 ms every time the loop runs. And when Android tries to update the UI, you make the thread sleep which means during this time period UI thread will not do anything. And this happens till your loop finishes. After your loop ends, the final event gets executed and you will see your UI updated by the call of addEntry() with the latest value passed.

Solution -

You can use postDelayed()-

new Handler().postDelayed(new Runnable() {
                        @Override
                        public void run() {
                           //Perform your task and it will be executed after 100 ms
                        }
                    },100);