개발자 노트

The Problem I was facing an issue where the spacing between the question, image, and options was excessively large, resulting in poor readability. On top of that, constraint conflicts were occurring. The root cause was that it is mathematically impossible for Auto Layout to satisfy the following three constraints simultaneously: 20pt spacing from the question to the image view. 10pt spacing from the question label to the options stack view. 20pt spacing from the image view to the options stack view. The Solution To resolve this, I made the constraints dynamic. First, declare variables for the constraints: Swift private var questionToOptionsConstraint: NSLayoutConstraint ! private var questionToImageConstraint: NSLayoutConstraint ! private var imageToOptionsConstraint: NSLayoutConstraint ! Next, initialize these constraints in the setupConstraints() method, but do not activate them yet: Swift questionToOptionsConstraint = optionsStackView.topAnchor.constraint(equalTo: questio...

1. Preventing Data Conflicts with a Composite Primary Key Problem Previously, the level and quizGroup were not distinctly separated in the database. As a result, saving new progress would unintentionally overwrite existing data from other levels. Solution I updated the progress table to use a composite primary key consisting of both level and quizGroup . This ensures that progress is managed independently for each specific level and group. SQL CREATE TABLE IF NOT EXISTS progress ( level TEXT, quizGroup TEXT, lastQuestionIndex INTEGER , PRIMARY KEY (level, quizGroup) ); 2. Improving the Data Saving Mechanism Updating Progress for a Specific Level and Group In the saveProgress method, I updated the SQL query to include both level and quizGroup in the WHERE clause. This ensures we only update the progress for the targeted level and group. Swift let updateQuery = "UPDATE progress SET lastQuestionIndex = ? WHERE level = ? AND quizGroup = ?;" Appl...