在mousedown上使用vanilla JavaScript跳转的自定义可调整大小的Flexbox视图

Question

我正在努力使4个视图容器中的每一个都可以调整大小。我希望它类似于Codepen。我开始时可以调整V1和V2的宽度。视图之间的蓝色边框是句柄。当我将mousedown突然放在手柄V2的宽度上并且尺寸明显增大时。 为什么会这样？

我的实现背后的想法是计算鼠标向下和鼠标向上x坐标位置之间的差异，然后将此计算的差异添加到容器的宽度（或技术上的柔性基础）。

Heres my codepen.感谢您的帮助。

HTML

<div id="views-cntnr">
  <div id="r1" class="view-row">
    <div id="v1" class="view">
      <div class="v-header">
        <button class="vh-btn v-settings"><i class="glyphicon glyphicon-cog"></i></button>
        <span class="v-title">R-Theta</span>
        <button class="vh-btn v-close"><i class="glyphicon glyphicon-remove"></i></button>
      </div>
    </div>
    <div class="handle" id="r1-l-r">
    </div>
    <div id="v2" class="view">
      <div class="v-header">
        <button class="vh-btn v-settings"><i class="glyphicon glyphicon-cog"></i></button>
        <span class="v-title">Cartesian</span>
        <button class="vh-btn v-close"><i class="glyphicon glyphicon-remove"></i></button>
      </div>
    </div>
  </div>
  <div id="r2" class="view-row">
    <div id="v3" class="view">
      <div class="v-header">
        <button class="vh-btn v-settings"><i class="glyphicon glyphicon-cog"></i></button>
        <span class="v-title">Longitudinal</span>
        <button class="vh-btn v-close"><i class="glyphicon glyphicon-remove"></i></button>
      </div>
    </div>
  </div>
  <div id="r3" class="view-row">
    <div id="v4" class="view">
      <div class="v-header">
        <span class="v-title">Console</span>
        <button class="vh-btn v-close"><i class="glyphicon glyphicon-remove"></i></button>
      </div>
    </div>
  </div>
</div>

CSS

html,
body {
  height: 100%;
}

/* VIEWS */



/* VIEW HEADERS */

.v-header {
  position: relative;
  padding: 3px;
  border-bottom: #bfbfbf 1px solid;
  background-color: #1a1b1c;
  color: #ccc;
  font-weight: 900;
  font-size: 16px;
}

.v-title {
  position: relative;
  left: 35px;
}

#v4 .v-title {
  left: 6px;
}


/*VIEW BTNS */

.vh-btn {
  padding: 2px 8px;
  border-radius: 4px;
  font-size: 10px;
  background-color: #343436;
  color: white;
  border: black 1px solid;
  position: absolute;
  top: 4px;
}

.vh-btn:hover {
  background-color: #4d4d50;
}

.v-settings {
  left: 6px;
}

.v-close {
  right: 5px;
}


/* view btns */


/* view headers */

#views-cntnr {
  display: flex;
  flex-direction: column;
  height: 100%;
}

/* HANDLES */

#r1-l-r {
  background-color: DodgerBlue;
  width: 10px
}

/* handles */

/* ROWS */


/* ROW 1 */

#r1 {
  display: flex;
  flex-grow: 4;
}

#r1 .view {
  flex-grow: 1;
  border: #bfbfbf 1px solid;
  border-top: none;
  border-right: none;
}

#r1 .view:last-child {
  border-left: none;
}


/* row 1 */


/* ROW 2 */

#r2 .view {
  border: #bfbfbf 1px solid;
  border-top: none;
  flex-grow: 1;
}

#r2 {
  display: flex;
  flex-grow: 3;
}


/* row 2 */


/* ROW 3 */

#r3 .view {
  border: #bfbfbf 1px solid;
  border-top: none;
  flex-grow: 1;
}

#r3 {
  display: flex;
  flex-grow: 2;
}


/* row 3 */


/* rows */


/* views */

JS

var mouseStartPosition = {};
var v1StartWidth;

var v1 = document.getElementById('v1');
var v2 = document.getElementById('v2');
var r1_lr_handle = document.getElementById('r1-l-r');

r1_lr_handle.addEventListener("mousedown", mousedownR1RL);

function mousedownR1RL(e) {
  // get v1 width
  v1StartWidth = v1.offsetWidth;
  // get mouse position
  mouseStartPosition.x = e.pageX;
  mouseStartPosition.y = e.pageY;

  console.log('start... x:', mouseStartPosition.x, 'y:', mouseStartPosition.y);

  // add listeners for mousemove, mouseup
  window.addEventListener("mousemove", mousemove);
  window.addEventListener("mouseup", mouseup);
}

function mousemove(e) {
  console.log('mouse move... x:', e.pageX, 'y:', e.pageY);
  var diff = mouseStartPosition.x - e.pageX;
  v2.style.flexBasis = v1StartWidth + diff + 'px';
}

function mouseup(e) {
  window.removeEventListener("mousemove", mousemove);
  window.removeEventListener("mouseup", mouseup);
}

Answer 1

尝试更新两个框的大小。当您仅更新一个时，浏览器会尝试增大未更新的框。它适用于JS的这个小更新。

var mouseStartPosition = {};
var v1StartWidth;
var v2StartWidth;

var v1 = document.getElementById('v1');
var v2 = document.getElementById('v2');
var r1_lr_handle = document.getElementById('r1-l-r');

r1_lr_handle.addEventListener("mousedown", mousedownR1RL);

function mousedownR1RL(e) {
  // get v1 width
  v1StartWidth = v1.offsetWidth;
  v2StartWidth = v2.offsetWidth;
  // get mouse position
  mouseStartPosition.x = e.pageX;
  mouseStartPosition.y = e.pageY;

  console.log('start... x:', mouseStartPosition.x, 'y:', mouseStartPosition.y);

  // add listeners for mousemove, mouseup
  window.addEventListener("mousemove", mousemove);
  window.addEventListener("mouseup", mouseup);
}

function mousemove(e) {
  // console.log('mouse move... x:', e.pageX, 'y:', e.pageY);
  var diff = mouseStartPosition.x - e.pageX;
    v1.style.flexBasis = v1StartWidth + -1*diff + 'px';
    v2.style.flexBasis = v2StartWidth + diff + 'px';
}

function mouseup(e) {
  window.removeEventListener("mousemove", mousemove);
  window.removeEventListener("mouseup", mouseup);
}