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Testing and Issues

You can test this app and submit issues during the testing period of the Android Chart contest.

Entries with serious issues will not be able to win the contest, but even minor issues might be important for overall results.


by rating


Fair Mammoth Apr 28, 2019 at 13:26
– The design doesn't comply with the guidelines.
– Very slow overall: vertical scrolling, scaling and filtering the graphs.
– Bonus goal is implemented, however the expected animations are missing.
– Lots of minor issues: a long tap on data filters doesn't work, 'All' values are missing (graph #3), percentage is missing (graph #5), etc.
LG Nexus 5X, Android 8.1.0; Samsung Galaxy J7, Android 8.1.0
Does not match designs. Glitch on vertical scroll. Values axis at chart 4 is not rounded to millions
Happy Hare Apr 18, 2019 at 03:55
1. I am an artist, thats my vision
2. What glitch at vertical scroll? There is no any!
3. Why should they be rounded to millions?
UNUSABLE performance: laggy scrolling/ enable/disable / tooltip mode
Xiaomi A1 / Android 9
Happy Hare Apr 18, 2019 at 06:35
There several methods to create this charts. Every method has its advantages and disadvantages. This methods are:
1. Extends view, and override onDraw
2. Use surfaceview, draw in thread
3. Use opengl, draw in thread

1. Method
+: fast develdevelop, no cpu(gpu) usage on user idle, easy reusing
-: high cpu(gpu) load on touch, hard animation. All such apps have problems with stackedbar (if there is no doublebuffer, some bars sometimes doesn't drawn)

2. +: user control of cpu usage, easy to animate
-: more time to develop, redrawing thread is always present, harder to reuse

3. Like 2, +: take less app ram

I've choosed the first method of chart creation, because of lack of time and opportunity to reuse code beside contest.
As the result, everytime you touch any view, it makes calculations and invalidating. When you doesn't touch, there are no usage.
Incorrect design, insufficient speed.
Samsung Galaxy S4, Android 5.0.1
Can't select piece of pie
Xiaomi A1 / Android 9
Happy Hare Apr 18, 2019 at 03:59
Yes. You can't select. What for?
Range not working in a zoomed mode
Xiaomi A1 / Android 9
Happy Hare Apr 18, 2019 at 04:02
Yes. It doesn't work in zoomed mode. Zoomed mode shows only selected day by hours. When range changes, there are many days. Which should I show?
Rangebar works only at chart #5, where all days are summed
chart view doesn't match chart under range selector
Xiaomi A1 / Android 9
Happy Hare Apr 18, 2019 at 04:07
Yes. It was planned so. Chartbar doesn't show disabled items, but rangebar shows everything everytime. Why? Because of goal of this bars:
Rangebar is for global vision
Graphbar is for detailed vision
Incrorrect graph type are displayed under range: no stacked bar in #5; no line graph in #4; no 2Y-graph under #2. for every chart it doesn't switch preview to zoomed mode
Happy Hare Apr 18, 2019 at 04:18
1. Why there should be stackedbar under #5? As I remember it is like on video, provided by telegram. Chartbar shows areas or pies, so where should be stackedbar? O_o
2. In zoomed mode of #4 there are graphs. Just make long press.
3. Yes, as it was told in previews issue, it was such a plan in #2
4. What is preview? If you mean rangebar - yes, thats was such a plan.
My answers for your questions (Can't reply directly):
1. >There several methods to create this charts.... blah blah blah
Answer: you could use drawLines with correct Paint settings (like no round cap etc.) more than 80% participants implemented MUCH MUCH better performance especially on line graphs using CANVAS (your first option).
2. >Yes. You can't select. What for?
Answer: this was in specs (see screenshot Android_11 from telegram team)
3. >Yes. It doesn't work in zoomed mode. Zoomed 
Answer: See video with 1 bonus from telegram team. Zoomed mode displays 168-hours timeline, and by default 24-hours are selected, and you can adjust it.
4. Yes. It was planned so
Answer: No, see the specs, for example 1st video from announce
5. Why there should be stackedbar under #5? 
Answer: It should be displayed after transition to PIE (see specs), the same for other graphs
Xiaomi A1 / Android 9
Nobody added any issues yet...