android studio 简单二维码扫描实现

要实现扫一扫功能首先要在AndroidManifest.xml中加入一些权限

其次在

**例如：**  android:name=".MyApplication"

在build.gradle文件中加入一些权限

apply plugin: 'com.android.application'

android {
    compileSdkVersion 27
    defaultConfig {
        applicationId "com.example.ewm"
        minSdkVersion 15
        targetSdkVersion 27
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
    //主要加入这段代码以及下面的两个权限
    **configurations.all {
        resolutionStrategy.eachDependency { DependencyResolveDetails details ->
            def requested = details.requested
            if (requested.group == 'com.android.support') {
                if (!requested.name.startsWith('multidex')) {
                    details.useVersion '27.1.1' //这里改为你项目使用的版本即可
                }
            }
        }
    }**
}
dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'com.android.support:appcompat-v7:27.1.1'
    implementation 'com.android.support.constraint:constraint-layout:1.1.3'
    **implementation 'com.android.support:design:27.1.1'//加入两个依赖
    compile 'cn.yipianfengye.android:zxing-library:1.9'**
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'com.android.support.test:runner:1.0.2'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
}

首先在布局中创建一个按钮，为点击扫描二维码的按钮

在主Actvity中实现其功能

package com.example.ewm;

import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.Toast;

import com.uuzuche.lib_zxing.activity.CaptureActivity;
import com.uuzuche.lib_zxing.activity.CodeUtils;

public class MainActivity extends Activity {

    private Button btns;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        //找控件
        btns = findViewById(R.id.btns);
    

        //扫描二维码功能
        btns.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
            
                Intent intent = new Intent(MainActivity.this,CaptureActivity.class);
                startActivityForResult(intent,1);
            }
        });
    }
    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        /**
         * 处理二维码的扫描结果
         */
        if (requestCode == 1){
            //处理扫描结果(在界面上显示)
            if (data != null){
                Bundle bundle = data.getExtras();
                if (bundle == null){
                    return;
                }
                if (bundle.getInt(CodeUtils.RESULT_TYPE) == CodeUtils.RESULT_SUCCESS){
                    String result = bundle.getString(CodeUtils.RESULT_STRING);
                    Toast.makeText(this,"解析结果"+result,Toast.LENGTH_LONG).show();
                }else if (bundle.getInt(CodeUtils.RESULT_TYPE) == CodeUtils.RESULT_FAILED){
                    Toast.makeText(this,"解析二维码失败",Toast.LENGTH_LONG).show();
                }
            }
        }
    }
}

//不要忘记还需要一个工具类

package com.example.ewm;

import android.app.Application;

import com.uuzuche.lib_zxing.activity.ZXingLibrary;

public class MyApplication extends Application {
    @Override
    public void onCreate() {
        super.onCreate();
        ZXingLibrary.initDisplayOpinion(this);
    }
}