[移动开发]端计算(8)-android kotlin(1)

viewBinding

SpxLearnActivity.kt

package com.example.s2

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle

import android.widget.Toast
import com.example.s2.databinding.L1LayoutBinding



class SpxLearnActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)

        val binding=L1LayoutBinding.inflate(layoutInflater)
        setContentView(binding.root)
        binding.bt1.setOnClickListener{
                Toast.makeText(this,"你好，世界",Toast.LENGTH_SHORT).show()
        }

    }
}

l1_layout.xml

plugins {
    id 'com.android.application'
    id 'kotlin-android'
    id 'kotlin-parcelize'
}

android {
    compileSdk 30
    defaultConfig {
        applicationId "com.example.s2"
        minSdk 21
        targetSdk 30
        versionCode 1
        versionName "1.0"

        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
    }
    viewBinding {
        enabled = true
    }
    buildTypes {


        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }

    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }
    kotlinOptions {
        jvmTarget = '1.8'
    }

}

dependencies {

    implementation 'androidx.core:core-ktx:1.3.2'
    implementation 'androidx.appcompat:appcompat:1.2.0'
    implementation 'com.google.android.material:material:1.3.0'
    testImplementation 'junit:junit:4.+'
    androidTestImplementation 'androidx.test.ext:junit:1.1.2'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.3.0'
}

activity 调用另一个activity
AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.s2">

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/Theme.S2">
        <activity
            android:name=".AddActivity">
            <intent-filter>
                <action android:name="com.example.s2.ACTION_ADDS" />
                <category android:name="android.intent.category.DEFAULT" />
            </intent-filter>
        </activity>
        <activity
            android:name=".SpxLearnActivity"
            android:label="my first activity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

SpxLearnActivity.kt

package com.example.s2

import android.content.Intent
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.view.Menu
import android.view.MenuItem

import android.widget.Toast
import com.example.s2.databinding.L1LayoutBinding




class SpxLearnActivity : AppCompatActivity() {
    override fun onCreateOptionsMenu(menu: Menu?): Boolean {
        menuInflater.inflate(R.menu.l1_menu,menu)
        return true//super.onCreateOptionsMenu(menu)
    }

    override fun onOptionsItemSelected(item: MenuItem): Boolean {
        when (item.itemId){
            R.id.add_item->Toast.makeText(this,"增加完毕",Toast.LENGTH_SHORT).show()
            R.id.remove_item->Toast.makeText(this,"减少完毕",Toast.LENGTH_SHORT).show()
        }
        return true
    }

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)

        val binding=L1LayoutBinding.inflate(layoutInflater)

        setContentView(binding.root)
        binding.bt1.setOnClickListener{
            Toast.makeText(this,"你好，世界",Toast.LENGTH_SHORT).show()
            val intent= Intent("com.example.s2.ACTION_ADDS")
            startActivity(intent)
        }

    }
}

AddActivity.kt

package com.example.s2

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.widget.Toast
import com.example.s2.databinding.ActivityAddBinding

class AddActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_add)
        val binding= ActivityAddBinding.inflate(layoutInflater)
        binding.bt1.setOnClickListener{
            //Toast.makeText(this,"增加", Toast.LENGTH_SHORT).show()
            this.finish()
        }
    }
}

activity_add.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=".AddActivity">

    <Button
        android:id="@+id/bt1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="return"
        tools:ignore="MissingConstraints"
        tools:layout_editor_absoluteX="49dp"
        tools:layout_editor_absoluteY="77dp" />


</androidx.constraintlayout.widget.ConstraintLayout>

自定义category

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.s2">

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/Theme.S2">
        <activity
            android:name=".AddActivity">
            <intent-filter>
                <action android:name="com.example.s2.ACTION_ADDS" />
                <category android:name="android.intent.category.DEFAULT"/>
                <category android:name="com.example.s2.ADD_CATEGORY"/>
            </intent-filter>
        </activity>
        <activity
            android:name=".SpxLearnActivity"
            android:label="my first activity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

package com.example.s2

import android.content.Intent
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.view.Menu
import android.view.MenuItem

import android.widget.Toast
import com.example.s2.databinding.L1LayoutBinding




class SpxLearnActivity : AppCompatActivity() {
    override fun onCreateOptionsMenu(menu: Menu?): Boolean {
        menuInflater.inflate(R.menu.l1_menu,menu)
        return true//super.onCreateOptionsMenu(menu)
    }

    override fun onOptionsItemSelected(item: MenuItem): Boolean {
        when (item.itemId){
            R.id.add_item->Toast.makeText(this,"增加完毕",Toast.LENGTH_SHORT).show()
            R.id.remove_item->Toast.makeText(this,"减少完毕",Toast.LENGTH_SHORT).show()
        }
        return true
    }

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)

        val binding=L1LayoutBinding.inflate(layoutInflater)

        setContentView(binding.root)
        binding.bt1.setOnClickListener{
            Toast.makeText(this,"你好，世界",Toast.LENGTH_SHORT).show()
            val intent= Intent("com.example.s2.ACTION_ADDS")
            intent.addCategory("com.example.s2.ADD_CATEGORY")
            startActivity(intent)
        }

    }
}