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I see so many apps that their ui designed using photoshop-like programs, i just was asking about how custom UIs (something like this) that have been designed using such programs can be imported to android app project (for example) , and combined like what we can see in a good designed apps?
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Answers
You can refer Material design. The Photoshop just design image for your style app. May be jpg, png, gif,… Example the progress you share this link. I think u can’t not style for your app just only with Photoshop or like programs.
@user3446273, photoshop is only a design tool to create the look and feel of the APP UI. To replicate or use the UI in your android project, you can export parts of the UI as PNGs and include them in the android project.
In most cases, people slice relevant portions (example: icons, buttons) of the UI in photoshop and save the slices as JPG or PNG. These JPG or PNG files are imported into Android project code.
Before you start designing the UI, it is recommended that you read the Android UI guidelines.
HTH.
Generally designers use photoshop to design a new layouts.They follow the guidelines of google material design for android and guidelines for ios.They have to design apps in all sizes respective to phone resolutions for eg lets say iphone 6 plus ,its resolution is 1080×1920 but designers have to built 1242×2208.They use their creatvity and design apps.Then they have to slice icons,buttons,images,backgrounds .. etc so i hope you got your answer