优化picker_group里面props改变或者初始化时获取translate和slected，更改select为selectedIndex

weui · Mar 22, 2017 · b58a43d · b58a43d
1 parent 01bc1c5
commit b58a43d
Showing 1 changed file with 31 additions and 37 deletions.
diff --git a/src/components/picker/picker_group.js b/src/components/picker/picker_group.js
@@ -36,7 +36,7 @@ class PickerGroup extends Component {
             touchId: undefined,
             translate: 0,
             totalHeight: 0,
-            selected: 0,
+            selectedIndex: 0,
             animating: this.props.animation
         };
 
@@ -54,51 +54,45 @@ class PickerGroup extends Component {
         this.adjustPosition(nextProps);
     }
 
-    adjustPosition(props){
-        const { items, itemHeight, indicatorTop, defaultIndex } = props;
+    adjustPosition(props) {
+        const { items, defaultIndex, itemHeight, indicatorTop, indicatorHeight } = props;
         const totalHeight = items.length * itemHeight;
-        let translate = totalHeight <= indicatorTop ? indicatorTop : 0;
+        let { translate } = this.state;
 
         if (defaultIndex > -1) {
-            if (translate === 0){
-                let upperCount = Math.floor(indicatorTop / itemHeight);
-                if ( defaultIndex > upperCount ){
-                    //over
-                    let overCount = defaultIndex - upperCount;
-                    translate -= overCount * itemHeight;
-                } else if ( defaultIndex === upperCount){
-                    translate = 0;
-                } else {
-                    //less
-                    translate += ( Math.abs(upperCount - defaultIndex) * itemHeight);
-                }
-                //if(props.groupIndex == 2) console.log(defaultIndex,translate, upperCount)
-            } else {
-                //total item less than indicator height
-                translate -= itemHeight * defaultIndex;
-            }
+            translate = indicatorTop - itemHeight * defaultIndex;
         }
 
-    	this.setState({
-    	    selected: defaultIndex,
-    	    ogTranslate: translate,
-    	    totalHeight,
-    	    translate,
-    	}, () => defaultIndex > -1 ? this.updateSelected(false) : this.updateSelected() );
+        this.setState({
+            selectedIndex : defaultIndex,
+            ogTranslate   : translate,
+            totalHeight,
+            translate,
+        }, () => {if (defaultIndex <= -1) this.updateSelected()});
     }
 
-    updateSelected(propagate = true){
-        const { items, itemHeight, indicatorTop, indicatorHeight, onChange, groupIndex } = this.props;
-        let selected = 0;
-        items.forEach( (item, i) => {
-            //console.log(i, this.state.translate, (this.state.translate + (itemHeight * i)), indicatorTop, this.state.translate + (itemHeight * i) + itemHeight , indicatorTop + indicatorHeight)
-            if ( !item.disabled && (this.state.translate + (itemHeight * i)) >= indicatorTop &&
-            ( this.state.translate + (itemHeight * i) + itemHeight ) <= indicatorTop + indicatorHeight ){
-                selected = i;
+    adjustSelectedIndex() {
+        const { items, itemHeight, indicatorTop, indicatorHeight } = this.props;
+        const { translate } = this.state;
+        let selectedIndex = 0;
+
+        for (let i = 0; i < items.length; i++) {
+            if (!items[i].disabled && (itemHeight * i + translate) >= indicatorTop
+                && ((i + 1) * itemHeight + translate) <= indicatorTop + indicatorHeight){
+                selectedIndex = i;
+                break;
             }
-        });
+        }
+
+        return selectedIndex;
+    }
 
-        if (onChange && propagate) onChange(items[selected], selected, groupIndex);
+    updateSelected() {
+        const { items, onChange, groupIndex } = this.props
+        const selectedIndex = this.adjustSelectedIndex()
+        if (onChange) {
+            onChange(items[selectedIndex], selectedIndex, groupIndex);
+        }
     }
 
     handleTouchStart(e){