fix "cache" 垃圾回收

@@ -155,5 +155,27 @@ App({
                 }
                 }
             })
             })
         })
         })
+    },
+    onHide(){
+        console.log('obHide');
+        let time=new Date()/1000;
+        wx.getStorageInfo({
+            success:(res)=>{
+                console.log(res.keys);
+                if(res.keys.length>0){
+                    res.keys.forEach(key=>{
+                        wx.getStorage({
+                            key:key,
+                            success:(ca)=>{
+                                //console.log('obHide',ca.data.timeout,time);
+                                if(ca.data.timeout && ca.data.timeout<time){
+                                    wx.removeStorage({key:key})
+                                }
+                            }
+                        })
+                    })
+                }
+            },
+        })
     }
     }
 })
 })