How to use transform:translateX to move a child element horizontally 100

Question

All,

I\'d like to be able to use translateX to animate a child element 100% of the way across it\'s parent (i.e., from the left edge to the right edge).

Answer 1

I didn't post my idea originally, because it involves creating an additional HTML layer, and expected better solutions to come.

Since that hasn't happened, I explain my comment. What I meant was this:

#parent {
    position: relative;
    width: 300px;
    height: 100px;
    background-color: black;
}
#wrapper {
    position: absolute;
    width: 100%;
    height: 100px;
    border: solid 1px green;
    transition: all 1s;
}
#wrapper:hover {
    -webkit-transform: translateX(100%);
    transform: translateX(100%);
}
#child {
    position: absolute;
    width: 20px;
    height: 100px;
    background-color:red;
}
#wrapper:hover #child {
    -webkit-transform: translateX(-100%);
    transform: translateX(-100%);
}

Since the wrapper is 100% width of the parent, translating it 100% works as expected.

fiddle

Note that the wrapper is being translated 100% as you stated. However, seems that what you really want is to move the element 100% - width. To achieve this, you have to translate the child also 100% (now this applies to the child width) in the opposite direction.

Correction: the child should share the transition property of the wrapper:

#parent {
    position: relative;
    width: 300px;
    height: 100px;
    background-color: black;
}
#wrapper {
    position: absolute;
    width: 100%;
    height: 100px;
    border: solid 1px green;
    transition: all 5s;
}
#wrapper:hover {
    transform: translateX(100%);
}
#child {
    position: absolute;
    width: 50px;
    height: 100px;
    background-color:red;
    transition: inherit;
}
#wrapper:hover #child {
    transform: translateX(-100%);
}