Android类似微信首页的页面开发教程(Kotlin)

前提条件

安装并配置好Android Studio

Android Studio Electric Eel | 2022.1.1 Patch 2
Build #AI-221.6008.13.2211.9619390, built on February 17, 2023
Runtime version: 11.0.15+0-b2043.56-9505619 amd64
VM: OpenJDK 64-Bit Server VM by JetBrains s.r.o.
Windows 11 10.0
GC: G1 Young Generation, G1 Old Generation
Memory: 1280M
Cores: 6
Registry:
    external.system.auto.import.disabled=true
    ide.text.editor.with.preview.show.floating.toolbar=false
    ide.balloon.shadow.size=0
 
Non-Bundled Plugins:
    com.intuit.intellij.makefile (1.0.15)
    com.github.setial (4.0.2)
    com.alayouni.ansiHighlight (1.2.4)
    GsonOrXmlFormat (2.0)
    GLSL (1.19)
    com.mistamek.drawablepreview.drawable-preview (1.1.5)
    com.layernet.plugin.adbwifi (1.0.5)
    com.likfe.ideaplugin.eventbus3 (2020.0.2)

gradle-wrapper.properties

#Tue Apr 25 13:34:44 CST 2023
distributionBase=GRADLE_USER_HOME
distributionUrl=https\://services.gradle.org/distributions/gradle-7.4-bin.zip
distributionPath=wrapper/dists
zipStorePath=wrapper/dists
zipStoreBase=GRADLE_USER_HOME

build.gradle(:Project)

// Top-level build file where you can add configuration options common to all sub-projects/modules.
plugins {
    id 'com.android.application' version '7.3.1' apply false
    id 'com.android.library' version '7.3.1' apply false
    id 'org.jetbrains.kotlin.android' version '1.7.20' apply false
}

setting.gradle

pluginManagement {
    repositories {
        google()
        mavenCentral()
        gradlePluginPortal()
    }
}
dependencyResolutionManagement {
    repositoriesMode.set(RepositoriesMode.FAIL_ON_PROJECT_REPOS)
    repositories {
        google()
        mavenCentral()
    }
}
rootProject.name = "logindemo"
include ':app'

对Kotlin语言有基本了解

创建新项目

首先，打开Android Studio并创建一个新项目。选择"Empty Activity"模板，然后为项目命名，例如"###Demo"。接下来，选择Kotlin作为开发语言，并确保选择了合适的最小SDK版本。

添加依赖库

在项目的build.gradle（Module）文件中，添加以下依赖库：

dependencies {
    implementation 'com.google.android.material:material:1.5.0'
}

同步Gradle后，我们可以使用Material Design组件库中的TabLayout和ViewPager。

设计首页界面

在activity_main.xml文件中，我们将创建一个包含TabLayout和ViewPager的布局。

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <com.google.android.material.tabs.TabLayout
        android:id="@+id/tabLayout"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        app:layout_constraintBottom_toBottomOf="parent"
        app:tabIndicatorColor="@color/teal_200"
        app:tabSelectedTextColor="@color/teal_200"
        app:tabTextColor="@color/black" />

    <androidx.viewpager.widget.ViewPager
        android:id="@+id/viewPager"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintBottom_toTopOf="@+id/tabLayout"/>

</androidx.constraintlayout.widget.ConstraintLayout>

创建Fragment

为了实现类似微信的滑动切换功能，我们需要创建几个Fragment。在本教程中，我们将创建三个Fragment，分别代表“聊天”、“联系人”和“发现”。

package com.example.logindemo.fragment

import android.os.Bundle
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import androidx.fragment.app.Fragment
import com.example.logindemo.R

class ChatFragment : Fragment() {

    override fun onCreateView(
        inflater: LayoutInflater, container: ViewGroup?,
        savedInstanceState: Bundle?
    ): View? {
        return inflater.inflate(R.layout.fragment_chat, container, false)
    }
}

package com.example.logindemo.fragment

import android.os.Bundle
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import androidx.fragment.app.Fragment
import com.example.logindemo.R

class ContactsFragment : Fragment() {

    override fun onCreateView(
        inflater: LayoutInflater, container: ViewGroup?,
        savedInstanceState: Bundle?
    ): View? {
        return inflater.inflate(R.layout.fragment_contacts, container, false)
    }
}

package com.example.logindemo.fragment

import android.os.Bundle
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import androidx.fragment.app.Fragment
import com.example.logindemo.R

class DiscoverFragment : Fragment() {

    override fun onCreateView(
        inflater: LayoutInflater, container: ViewGroup?,
        savedInstanceState: Bundle?
    ): View? {
        return inflater.inflate(R.layout.fragment_discover, container, false)
    }
}

fragment_chat.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        android:text="聊天"/>

</androidx.constraintlayout.widget.ConstraintLayout>

fragment_contacts.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        android:text="联系人"/>

</androidx.constraintlayout.widget.ConstraintLayout>

fragment_discover.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        android:text="发现"/>

</androidx.constraintlayout.widget.ConstraintLayout>

设置ViewPager和TabLayout

在MainActivity.kt文件中，我们将设置ViewPager和TabLayout，以实现滑动切换功能。

package com.example.logindemo

import android.os.Bundle
import androidx.appcompat.app.AppCompatActivity
import androidx.fragment.app.Fragment
import androidx.fragment.app.FragmentPagerAdapter
import androidx.viewpager.widget.ViewPager
import com.example.logindemo.fragment.ChatFragment
import com.example.logindemo.fragment.ContactsFragment
import com.example.logindemo.fragment.DiscoverFragment
import com.google.android.material.tabs.TabLayout

class MainActivity : AppCompatActivity() {

    private lateinit var viewPager: ViewPager
    private lateinit var tabLayout: TabLayout

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        val fragments = listOf(
            ChatFragment(),
            ContactsFragment(),
            DiscoverFragment()
        )
        viewPager = findViewById(R.id.viewPager)
        tabLayout = findViewById(R.id.tabLayout)

        viewPager.adapter = ViewPagerAdapter(supportFragmentManager, fragments)
        tabLayout.setupWithViewPager(viewPager)

        tabLayout.getTabAt(0)?.text = "聊天"
        tabLayout.getTabAt(1)?.text = "联系人"
        tabLayout.getTabAt(2)?.text = "发现"
    }

    class ViewPagerAdapter(
        fragmentManager: androidx.fragment.app.FragmentManager,
        private val fragments: List<Fragment>
    ) : FragmentPagerAdapter(fragmentManager, BEHAVIOR_RESUME_ONLY_CURRENT_FRAGMENT) {

        override fun getItem(position: Int): Fragment {
            return fragments[position]
        }

        override fun getCount(): Int {
            return fragments.size
        }
    }
}

我们已经完成了模仿微信首页的Android应用开发。运行应用，你将看到一个类似于微信的首页界面，可以通过滑动或点击TabLayout切换不同的Fragment。