I got Lottie files from the designer and it contains png files.
The size are small. However, it seems low quality. And I added it into the view and built and launched my app and It looks blurry.
What I guess is, The parts Lottie can't vectorize remains as PNG files. And the others are in json.
Is that right?
If yes, The second question is, Lottie has some functionality to use PNG files like vectorized image source with its connected json file?
I need to correspond the device screens(resolutions). Does json+PNG can correspond all the resolutions or not? If it is not, Should I separate them and for the PNG part, I need mdpi, hdpi, xdpi, ... ones like in Zeplin?
Lottie Library supports PNG files but I think your designer made a mistake, it's better to use Vectors ONLY Lottie cannot convert PNG images into the vectors, so you have to include them into your project
Lottie has some functionality to use PNG files like vectorized image source with its connected JSON file?
NO
Lottie doesn't make the PNG vectorized. However, your animation will run normally just like it's demo, there is no problem with functionality. Since it is not vectorized, the image can look blurry or broken.
I need to correspond the device screens(resolutions). Does json+PNG can correspond all the resolutions or not? If it is not, Should I separate them and for the PNG part, I need mdpi, hdpi, xdpi, ... ones like in Zeplin?
NO
I think you will be in trouble with multiple screen resolutions, after all, the PNG is just a PNG