[移动开发]Android Studio 移植zxing（扫一扫功能）详细教程

1、下载zxing库

链接：https://pan.baidu.com/s/1i9Zj68s4ogz8wtYG39l97A
提取码：xtbq

2、右键“zxinglibrary.zip”->"解压到zxinglibrary"得到文件夹“zxinglibrary”

3、打开Android Studio -> 文件 -> NEW ->新建项目 -> 选择"Empty Activity" ->下一步 -> 完成

4、切换到Project模式

5、导入zxing ：文件->New ->Import Module…

6、打开"build.gradle"

在dependencies中添加：classpath ‘com.github.dcendents:android-maven-gradle-plugin:1.4.1’ //添加
在allprojects ->repositories中添加： maven { url ‘https://jitpack.io’ }

7、将zxinglibrary->“build.gradle” 修改为如下内容：

apply plugin: 'com.android.library'

apply plugin: 'com.github.dcendents.android-maven'
group = 'com.github.yuzhiqiang1993'

android {
    compileSdkVersion 29

    defaultConfig {
        minSdkVersion 21
        targetSdkVersion 29
        versionCode 1
        versionName '1.0'
        multiDexEnabled true
        vectorDrawables.useSupportLibrary = true
    }
    buildToolsVersion = '29.0.3'


}

dependencies {
    implementation fileTree(include: ['*.jar'], dir: 'libs')
    api files('libs/core-3.4.1.jar')
    compileOnly "androidx.appcompat:appcompat:1.3.0"
    compileOnly "com.google.android.material:material:1.3.0"
    compileOnly "androidx.vectordrawable:vectordrawable:1.1.0"
    compileOnly "androidx.annotation:annotation:1.2.0"
    compileOnly "androidx.multidex:multidex:2.0.0"

}

8、文件->项目结构->dependencies->app->"+"->Module Dependency->zxinglibrary->确定

打开 app -> “bulid.gradle”，将minSdkVersion修改为21

9、添加权限 app->src->main->res->AndroidManifest.xml

添加：

10、在 activity_main.xml 中创建界面如下

打开activity_main.xml 代码模式，将EditText的inputType属性修改为“textMultiLine”

11、在MainActivity.java 中编写控制程序

package com.example.myapplication;

import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;

import android.Manifest;
import android.annotation.SuppressLint;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Build;
import android.os.Bundle;
import android.text.InputType;
import android.view.Gravity;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.Toast;

import com.yzq.zxinglibrary.android.CaptureActivity;
import com.yzq.zxinglibrary.common.Constant;
import com.yzq.zxinglibrary.encode.CodeCreator;

public class MainActivity extends AppCompatActivity {

    private static final int PHOTO_REQUEST_SAOYISAO = 0;
    private static final int REQUEST_CODE_SCAN = 1;
    Button btnStart,btnCreat;  //按键
    EditText mytest,inputStr;  //文字控件
    ImageView picture; //图片控件

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        btnStart = (Button) findViewById(R.id.button);  //按键映射
        btnStart.setOnClickListener(buttonConnectClick); //关联处理函数

        mytest = (EditText)findViewById(R.id.editText);//控件映射
        //设置EditText的显示方式为多行文本输入
        mytest.setInputType(InputType.TYPE_TEXT_FLAG_MULTI_LINE);
        //文本显示的位置在EditText的最上方
        mytest.setGravity(Gravity.TOP);
        //改变默认的单行模式
        mytest.setSingleLine(false);
        //水平滚动设置为False
        mytest.setHorizontallyScrolling(false);

        btnCreat = (Button) findViewById(R.id.button2);  
        btnCreat.setOnClickListener(buttonCreat);
        inputStr = (EditText)findViewById(R.id.editText2);  
        picture = (ImageView)findViewById(R.id.imageView);
    }

    // 扫一扫按钮点击事件
    private View.OnClickListener buttonConnectClick = new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            showReceive("启动相机");
            // 取得相机权限
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
                requestPermissions(new String[]{Manifest.permission.CAMERA}, PHOTO_REQUEST_SAOYISAO);
            }else{
                // 权限已经取得的情况下调用
                // 调用扫一扫
                Intent intent = new Intent(MainActivity.this, CaptureActivity.class);
                startActivityForResult(intent, REQUEST_CODE_SCAN);

            }
        }
    };

    // 扫一扫按钮点击事件
    private View.OnClickListener buttonCreat = new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            /*
             * contentEtString：字符串内容
             * w：图片的宽
             * h：图片的高
             * logo：不需要logo的话直接传null
             * */
            String str = inputStr.getText().toString();
            Bitmap bitmap = CodeCreator.createQRCode(str, 400, 400, logo);
            picture.setImageBitmap(bitmap);
        }
    };
    /**
     * 重写申请权限操作返回值的方法
     **/
    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        switch (requestCode){
            case PHOTO_REQUEST_SAOYISAO:
                if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED){
                    // 权限申请成功，扫一扫
                    Intent intent = new Intent(MainActivity.this, CaptureActivity.class);
                    startActivityForResult(intent, REQUEST_CODE_SCAN);
                }else{
                    Toast.makeText(this, "无相机调用权限，扫一扫功能无法使用，", Toast.LENGTH_SHORT).show();
                }
        }
    }

    private void showReceive(final String str)
    {
        runOnUiThread(new Runnable() {//修改界面的UI最好用Handle,这里力求简单,下几节再用
            @SuppressLint("WrongConstant")
            public void run() {
                mytest.setText(str);
            }
        });
    };

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        // 扫描二维码/条码回传
        if (requestCode == REQUEST_CODE_SCAN && resultCode == RESULT_OK) {
            if (data != null) {
                String content = data.getStringExtra(Constant.CODED_CONTENT);
                showReceive("扫描结果为：" + content);
            }
        }
    }
}

12、APP效果如下：

13、注意事项

布局错乱，自己解决