二维码的扫描、生成

二维码的应用是GitHub上的开源项目。下载地址为https://github.com/zxing/zxing

我写的这个笔记Demo，主要是进行二维码扫描，以及生成二维码图标。只用到这2个功能

GitHub上的那个开源库包括的内容远远大于这2个功能。所以我从网上下载了精简版的库，只支持二维码扫面和生成的

库的地址：http://download.csdn.net/detail/u013210620/9036083

先看主页面布局

activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/container"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.jikexueyuan.testqrcode.MainActivity"
    tools:ignore="MergeRootFrame" >

    <Button
        android:id="@+id/scan"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="開始扫描二维码" />
    <TextView 
        android:id="@+id/text"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="show"
        />
   <EditText 
       android:id="@+id/input"
       android:layout_width="fill_parent"
       android:layout_height="wrap_content"
       android:hint="请输入要编码的内容"
       />
   <Button 
       android:id="@+id/gen"
       android:layout_width="fill_parent"
       android:layout_height="wrap_content"
       android:text="生成二维码"
       />
   <ImageView 
       android:id="@+id/img"
       android:layout_width="wrap_content"
       android:layout_height="wrap_content"
       android:layout_gravity="center_horizontal"
       />

</LinearLayout>

MainActivity

package com.jikexueyuan.testqrcode;

import junit.framework.Test;

import com.google.zxing.WriterException;
import com.zxing.activity.CaptureActivity;
import com.zxing.encoding.EncodingHandler;

import android.app.Activity;
import android.app.ActionBar;
import android.app.Fragment;
import android.content.Intent;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;
import android.os.Build;

public class MainActivity extends Activity {
	//开启扫一扫
	private Button scanButton;
	//将扫一扫后的结果正确，显示出来
	private TextView text;
	//输入要进行生成二维码的text内容
	private EditText input;
	//開始生成二维码
	private Button genButton;
	//显示生成的二维码
	private ImageView img;

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

		scanButton = (Button) findViewById(R.id.scan);
		text = (TextView) findViewById(R.id.text);
		scanButton.setOnClickListener(new View.OnClickListener() {

			@Override
			public void onClick(View arg0) {
				Toast.makeText(MainActivity.this, "你写能够扫描条形码或者二维码",
						Toast.LENGTH_SHORT).show();
				//开启扫一扫的activity
				Intent startScan = new Intent(MainActivity.this,
						CaptureActivity.class);
				//待结果返回，RESULT_OK
				startActivityForResult(startScan, 0);
			}
		});

		input = (EditText) findViewById(R.id.input);
		genButton = (Button) findViewById(R.id.gen);
		img = (ImageView) findViewById(R.id.img);
		genButton.setOnClickListener(new View.OnClickListener() {

			@Override
			public void onClick(View arg0) {
				String in = input.getText().toString();
				if (in.equals("")) {
					Toast.makeText(MainActivity.this, "请输入文本",
							Toast.LENGTH_SHORT).show();
				} else {
					try {
						//createQRCode(String str,int widthAndHeight)
						Bitmap qrcode = EncodingHandler.createQRCode(in, 400);
						//显示出来
						img.setImageBitmap(qrcode);
					} catch (WriterException e) {
						e.printStackTrace();
					}
				}

			}
		});
	}

	/**
	 * 扫一扫，成功后返回值进行推断
	 */
	@Override
	protected void onActivityResult(int requestCode, int resultCode, Intent data) {
		super.onActivityResult(requestCode, resultCode, data);
		if (resultCode == RESULT_OK) {
			String result = data.getExtras().getString("result");
			text.setText(result);
		}
	}
}