Android system properties (SystemProperties)

1. System properties System properties are key-value pairs with special meanings in the system. We sometimes need to use system properties during the development process, such as getting the system software version, getting the device name, etc. Sometimes we also need to set custom properties. System properties are global and easy to access. 2. Get […]

Android–Gradle plug-in gradle-wrapper.properties

1. Android Studio version, Android Gradle plug-in version, Gradle version Android Studio uses Gradle to build code through the Android Gradle plug-in; After each upgrade of Android Studio, the Android Gradle plug-in is automatically updated, and the corresponding Gradle version will also change; Therefore, the following correspondence will be generated: (1) Correspondence between Android Studio […]

Solution to the mismatch between the field name in the JSON string and the field name in the Java class (use of @JsonProperty(“”) and @JSONField(name = “”))

1.1 Background 1.1.1 The so-called background, that is, what is the purpose and reason for writing this blog? Recently, I encountered a very strange requirement at work. I used WebService to adjust a third-party interface, but the return value of the third-party interface was an Xml structure. It was not surprising at first. But then […]

Design and implementation of smart property management website based on SSM

Get the source code at the end Development language: Java Java development tools: JDK1.8 Backend framework: SSM Front-end: developed using JSP technology Database: MySQL5.7 combined with Navicat management tool Server: Tomcat8.5 Development software: IDEA/Eclipse Is it a Maven project: Yes Table of Contents 1. Project Introduction 2. System functions 3. System project screenshots Administrator function […]

Solving errors in web projects, java.io.FileNotFoundException: druid.properties (the system cannot find the specified file); [spring factory decoupling development]

When using Tomcat9.0, spring5.0 framework original factory class decoupling, druid-1.0.9jar version, JDK9, MSQL8 version database to simulate web page login case, an error message that the druid.properties file cannot be found appears, the details are as follows [Case code posted at the end]; Normally speaking, the configuration file is placed under the src directory, and […]

3. Watch listeners, filters and computed properties in vue

watch, computed properties and filters 1. watch (listener) ==1, 1 shallow monitoring== 1.2 Deep monitoring 1.3 Summary 2. filter (filter) 2.1 Local filter 2.2 Global filter ==3. computed(computed attribute)== 3.1 Basic use of computed 3.2 Summary 3. 3 Shopping cart case 1. watch(listener) 1, 1 shallow monitoring Function: Monitor changes in data data grammar: new […]

Vue2 (2): calculated properties, monitoring properties

Article directory 1. Computed properties 1.1 Use interpolation syntax and methods to splice names 1.2 Use computed properties to splice names 1.3 Abbreviation of computed properties 1.4 Summary of computed properties 2. Monitoring attributes-watch 2.1 Weather case foreshadowing 2.2 Lead to monitoring attributes (1). Pass in the watch configuration when new Vue (2). Monitor through […]

Error: ERROR Cannot read properties of null (reading type)

ERROR Cannot read properties of null (reading type’) TypeError: Cannot read properties of null (reading type’) <template> <el-card> <el-row :gutter=”20″ class=”header”> <el-col :span=”7″> <el-input placeholder=”Please enter the product category name…” v-model=”queryForm.query” clearable></el-input> </el-col> <el-button type=”primary” :icon=”Search” @click=”initBigTypeList”>Search</el-button> <el-button type=”primary” :icon=”DocumentAdd” @click=”handleDialogValue()”>Add product category</el-button> </el-row> <el-table :data=”tableData” stripe style=”width: 100%”> <el-table-column prop=”id” label=”#ID” width=”80″ /> <el-table-column […]