简体   繁体   中英

How to update the background-image size dynamically in Javascript

I am new to programming and currently experimenting on my first mini-project - a word definition game.

I have an event listener on an input field, which changes the background image each time a certain score is reached. My issue is that each time the background image is changed, it loses it's CSS style properties, namely, backgroundSize = cover; .

I made a function to change the backgroundSize value to cover , and this only works if I call it in the console. I have also tried inline styles, to no effect.

I just can't get it to work through the javascript file (neither eventListener nor an if statement).

The loaded image is always set to auto , I need this to be "cover".

Any assistance will be much appreciated.

body {
    background: url("/IMG/moebius.jpg");
    -webkit-background-size: cover;
    -moz-background-size: cover;
    -o-background-size: cover;
    background-size: cover;
}


let changeBackground = () => {
    document.body.style.backgroundSize = "cover";
    return document.body.style.backgroundSize;
}


defInputField.addEventListener("keyup", () => {

    // document.body.style.backgroundSize = "cover";


    setTimeout(userScore, scoreInterval);
    if (splitInputWords.length < 2) {
        correct.style.display = "none";
        incorrect.style.display = "none";
        displayScore.style.display = "none";
    };

    if (totalScore > 5) {
        document.body.style.background = "url('/IMG/moebius3.jpg')";

    };

    if (totalScore > 10) {
        document.body.style.background = "url('/IMG/moebius.jpg')";

    };

    if (userScore() >= 3 || userScore() >= splitDisplayedDef().length) {
        correct.style.display = "block";
        incorrect.style.display = "none"
        displayScore.textContent = userScore();
        displayScore.style.display = "block";


    } else {
        incorrect.style.display = "none";
        correct.style.display = "none";
        displayScore.display ="none";
    }; 

});

defInputField.addEventListener("keydown", (e) => {



    if (e.keyCode === 13 && userScore() >= 1) {
            totalScore += userScore();
            totalScore--;
            currentLevel++;
            newDefButton.textContent = "Definition"
            let newWordObject = newWordObjectGenerator();
            displayNewDef.style.display = "none";
            correct.style.display = "none";
            incorrect.style.display = "none";
            displayScore.style.display = "none";    
            defInputField.value = "";
            displayNewWord.textContent = newWordObject.word;
            displayNewDef.textContent = newWordObject.definition;
            scoreTracker.textContent = "Total Score = " + " " + totalScore;
            levelTracker.textContent = "Level = " + " " + currentLevel;
            console.log(currentLevel);
            console.log(totalScore);

}});

use backgroundImage instead of background when u call an image path.

The technical post webpages of this site follow the CC BY-SA 4.0 protocol. If you need to reprint, please indicate the site URL or the original address.Any question please contact:yoyou2525@163.com.

 
粤ICP备18138465号  © 2020-2024 STACKOOM.COM