随着微信的到来，二维码越来越火爆，随处能看到二维码，比如商城里面，肯德基，餐厅等等，对于二维码扫描我们使用的是google的开源框架Zxing,我们可以去http://code.google.com/p/zxing/下载源码和Jar包，之前我项目中的二维码扫描功能只实现了扫描功能，其UI真的是其丑无比，一个好的应用软件，其UI界面也要被大众所接纳，不然人家就不会用你的软件啦，所以说应用软件功能和界面一样都很重要，例如微信，相信微信UI被很多应用软件所模仿，我也仿照微信扫描二维码效果进行模仿，虽然没有微信做的那么精致，但是效果还是可以的，所以将自己修改UI的代码和扫描二维码的代码分享给大家，一是自己以后项目遇到同样的功能直接拷贝来用，二是给还没有加入二维码功能的人一个参考，站在巨人的肩膀上,哈哈，我之前也是站在巨人的肩膀上加上此功能，接下来跟着我一步一步来实现此项功能，里面去除了很多不必要的文件
我们先看下项目的结构
如果你项目也想加入此功能，你直接将com.mining.app.zxing.camera，com.mining.app.zxing.decoding，com.mining.app.zxing.view这三个包拷贝到你的项目中，然后引入相对应的资源进去，我也是从我的项目中直接引用过来的，包名都没改呢，当然还需要引用Zxing.jar
com.example.qr_codescan包里面有一个MipcaActivityCapture,也是直接引入我之前项目的代码的，这个Activity主要处理扫描界面的类，比如，扫描成功有声音和振动等等，主要关注里面的handleDecode(Result result, Bitmap barcode)方法，扫描完成之后将扫描到的结果和二维码的bitmap当初参数传递到handleDecode(Result result, Bitmap barcode)里面，我们只需要在里面写出相对应的处理代码即可，其他的地方都不用改得，我这里处理扫描结果和扫描拍的照片
/**
* 处理扫描结果
* @param result
* @param barcode
*/
public void handleDecode(Result result, Bitmap barcode) {
inactivityTimer.onActivity();
playBeepSoundAndVibrate();
String resultString = result.getText();
if (resultString.equals("")) {
Toast.makeText(MipcaActivityCapture.this, "Scan failed!", Toast.LENGTH_SHORT).show();
}else {
Intent resultIntent = new Intent();
Bundle bundle = new Bundle();
bundle.putString("result", resultString);
bundle.putParcelable("bitmap", barcode);
resultIntent.putExtras(bundle);
this.setResult(RESULT_OK, resultIntent);
}
MipcaActivityCapture.this.finish();
}我对MipcaActivityCapture界面的布局做了自己的改动，先看下效果图，主要是用到FrameLayout,里面嵌套RelativeLayout。
布局代码如下
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<RelativeLayout
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<SurfaceView
android:id="@+id/preview_view"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_gravity="center" />
<com.mining.app.zxing.view.ViewfinderView
android:id="@+id/viewfinder_view"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<include
android:id="@+id/include1"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
layout="@layout/activity_title" />
</RelativeLayout>
</FrameLayout>
在里面我将界面上面部分写在另一个布局里面，然后include进来，因为这个activity_title在我项目里面还供其他的Activity使用，我也是直接拷贝出来的
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:background="@drawable/mmtitle_bg_alpha" >
<Button
android:id="@+id/button_back"
android:layout_width="75.0dip"
android:text="返回"
android:background="@drawable/mm_title_back_btn"
android:textColor="@android:color/white"
android:layout_height="wrap_content"
android:layout_centerVertical="true"
android:layout_marginLeft="2dip" />
<TextView
android:id="@+id/textview_title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBaseline="@+id/button_back"
android:layout_alignBottom="@+id/button_back"
android:layout_centerHorizontal="true"
android:gravity="center_vertical"
android:text="二维码扫描"
android:textColor="@android:color/white"
android:textSize="18sp" />
</RelativeLayout>
在我这个demo里面，有一个主界面MainActivity，里面一个Button， 一个ImageView和一个TextView,点击Button进入到二维码扫描界面，当扫描OK的时候，回到主界面，将扫描的结果显示到TextView，将图片显示到ImageView里面，然后你可以不处理图片，我这里随带的加上图片，主界面的布局很简单如下
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#ffe1e0de" >
<Button
android:id="@+id/button1"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:text="扫描二维码" />
<TextView
android:id="@+id/result"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_below="@+id/button1"
android:lines="2"
android:gravity="center_horizontal"
android:textColor="@android:color/black"
android:textSize="16sp" />
<ImageView
android:id="@+id/qrcode_bitmap"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_alignParentLeft="true"
android:layout_below="@+id/result"/>
</RelativeLayout>
MainActivity里面的代码如下，里面的功能在上面已经说了
package com.example.qr_codescan;
import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;
public class MainActivity extends Activity {
private final static int SCANNIN_GREQUEST_CODE = 1;
/**
* 显示扫描结果
*/
private TextView mTextView ;
/**
* 显示扫描拍的图片
*/
private ImageView mImageView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mTextView = (TextView) findViewById(R.id.result);
mImageView = (ImageView) findViewById(R.id.qrcode_bitmap);
//点击按钮跳转到二维码扫描界面，这里用的是startActivityForResult跳转
//扫描完了之后调到该界面
Button mButton = (Button) findViewById(R.id.button1);
mButton.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent();
intent.setClass(MainActivity.this, MipcaActivityCapture.class);
intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivityForResult(intent, SCANNIN_GREQUEST_CODE);
}
});
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
switch (requestCode) {
case SCANNIN_GREQUEST_CODE:
if(resultCode == RESULT_OK){
Bundle bundle = data.getExtras();
//显示扫描到的内容
mTextView.setText(bundle.getString("result"));
//显示
mImageView.setImageBitmap((Bitmap) data.getParcelableExtra("bitmap"));
}
break;
}
}
}
上面的代码还是比较简单，但是要想做出像微信那样只的扫描框，紧紧上面的代码是没有那种效果的，我们必须重写com.mining.app.zxing.view包下面的ViewfinderView类，微信里面的都是用的图片，我是自己画出来的，代码注释的比较清楚，大家直接看代码吧，相信你能理解的，如果你要修改扫描框的大小，去CameraManager类里面修改
/*
* Copyright (C) 2008 ZXing authors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* *
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.mining.app.zxing.view;
import java.util.Collection;
import java.util.HashSet;
import android.content.Context;
import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Rect;
import android.graphics.Typeface;
import android.util.AttributeSet;
import android.view.View;
import com.example.qr_codescan.R;
import com.google.zxing.ResultPoint;
import com.mining.app.zxing.camera.CameraManager;
/**
* This view is overlaid on top of the camera preview. It adds the viewfinder
* rectangle and partial transparency outside it, as well as the laser scanner
* animation and result points.
*
*/
public final class ViewfinderView extends View {
private static final String TAG = "log";
/**
* 刷新界面的时间
*/
private static final long ANIMATION_DELAY = 10L;
private static final int OPAQUE = 0xFF;
/**
* 四个绿色边角对应的长度
*/
private int ScreenRate;
/**
* 四个绿色边角对应的宽度
*/
private static final int CORNER_WIDTH = 10;
/**
* 扫描框中的中间线的宽度
*/
private static final int MIDDLE_LINE_WIDTH = 6;
/**
* 扫描框中的中间线的与扫描框左右的间隙
*/
private static final int MIDDLE_LINE_PADDING = 5;
/**
* 中间那条线每次刷新移动的距离
*/
private static final int SPEEN_DISTANCE = 5;
/**
* 手机的屏幕密度
*/
private static float density;
/**
* 字体大小
*/
private static final int TEXT_SIZE = 16;
/**
* 字体距离扫描框下面的距离
*/
private static final int TEXT_PADDING_TOP = 30;
/**
* 画笔对象的引用
*/
private Paint paint;
/**
* 中间滑动线的最顶端位置
*/
private int slideTop;
/**
* 中间滑动线的最底端位置
*/
private int slideBottom;
private Bitmap resultBitmap;
private final int maskColor;
private final int resultColor;
private final int resultPointColor;
private Collection<ResultPoint> possibleResultPoints;
private Collection<ResultPoint> lastPossibleResultPoints;
boolean isFirst;
public ViewfinderView(Context context, AttributeSet attrs) {
super(context, attrs);
density = context.getResources().getDisplayMetrics().density;
//将像素转换成dp
ScreenRate = (int)(20 * density);
paint = new Paint();
Resources resources = getResources();
maskColor = resources.getColor(R.color.viewfinder_mask);
resultColor = resources.getColor(R.color.result_view);
resultPointColor = resources.getColor(R.color.possible_result_points);
possibleResultPoints = new HashSet<ResultPoint>(5);
}
@Override
public void onDraw(Canvas canvas) {
//中间的扫描框，你要修改扫描框的大小，去CameraManager里面修改
Rect frame = CameraManager.get().getFramingRect();
if (frame == null) {
return;
}
//初始化中间线滑动的最上边和最下边
if(!isFirst){
isFirst = true;
slideTop = frame.top;
slideBottom = frame.bottom;
}
//获取屏幕的宽和高
int width = canvas.getWidth();
int height = canvas.getHeight();
paint.setColor(resultBitmap != null ? resultColor : maskColor);
//画出扫描框外面的阴影部分，共四个部分，扫描框的上面到屏幕上面，扫描框的下面到屏幕下面
//扫描框的左边面到屏幕左边，扫描框的右边到屏幕右边
canvas.drawRect(0, 0, width, frame.top, paint);
canvas.drawRect(0, frame.top, frame.left, frame.bottom + 1, paint);
canvas.drawRect(frame.right + 1, frame.top, width, frame.bottom + 1,
paint);
canvas.drawRect(0, frame.bottom + 1, width, height, paint);
if (resultBitmap != null) {
// Draw the opaque result bitmap over the scanning rectangle
paint.setAlpha(OPAQUE);
canvas.drawBitmap(resultBitmap, frame.left, frame.top, paint);
} else {
//画扫描框边上的角，总共8个部分
paint.setColor(Color.GREEN);
canvas.drawRect(frame.left, frame.top, frame.left + ScreenRate,
frame.top + CORNER_WIDTH, paint);
canvas.drawRect(frame.left, frame.top, frame.left + CORNER_WIDTH, frame.top
+ ScreenRate, paint);
canvas.drawRect(frame.right - ScreenRate, frame.top, frame.right,
frame.top + CORNER_WIDTH, paint);
canvas.drawRect(frame.right - CORNER_WIDTH, frame.top, frame.right, frame.top
+ ScreenRate, paint);
canvas.drawRect(frame.left, frame.bottom - CORNER_WIDTH, frame.left
+ ScreenRate, frame.bottom, paint);
canvas.drawRect(frame.left, frame.bottom - ScreenRate,
frame.left + CORNER_WIDTH, frame.bottom, paint);
canvas.drawRect(frame.right - ScreenRate, frame.bottom - CORNER_WIDTH,
frame.right, frame.bottom, paint);
canvas.drawRect(frame.right - CORNER_WIDTH, frame.bottom - ScreenRate,
frame.right, frame.bottom, paint);
//绘制中间的线,每次刷新界面，中间的线往下移动SPEEN_DISTANCE
slideTop += SPEEN_DISTANCE;
if(slideTop >= frame.bottom){
slideTop = frame.top;
}
canvas.drawRect(frame.left + MIDDLE_LINE_PADDING, slideTop - MIDDLE_LINE_WIDTH/2, frame.right - MIDDLE_LINE_PADDING,slideTop + MIDDLE_LINE_WIDTH/2, paint);
//画扫描框下面的字
paint.setColor(Color.WHITE);
paint.setTextSize(TEXT_SIZE * density);
paint.setAlpha(0x40);
paint.setTypeface(Typeface.create("System", Typeface.BOLD));
canvas.drawText(getResources().getString(R.string.scan_text), frame.left, (float) (frame.bottom + (float)TEXT_PADDING_TOP *density), paint);
Collection<ResultPoint> currentPossible = possibleResultPoints;
Collection<ResultPoint> currentLast = lastPossibleResultPoints;
if (currentPossible.isEmpty()) {
lastPossibleResultPoints = null;
} else {
possibleResultPoints = new HashSet<ResultPoint>(5);
lastPossibleResultPoints = currentPossible;
paint.setAlpha(OPAQUE);
paint.setColor(resultPointColor);
for (ResultPoint point : currentPossible) {
canvas.drawCircle(frame.left + point.getX(), frame.top
+ point.getY(), 6.0f, paint);
}
}
if (currentLast != null) {
paint.setAlpha(OPAQUE / 2);
paint.setColor(resultPointColor);
for (ResultPoint point : currentLast) {
canvas.drawCircle(frame.left + point.getX(), frame.top
+ point.getY(), 3.0f, paint);
}
}
//只刷新扫描框的内容，其他地方不刷新
postInvalidateDelayed(ANIMATION_DELAY, frame.left, frame.top,
frame.right, frame.bottom);
}
}
public void drawViewfinder() {
resultBitmap = null;
invalidate();
}
/**
* Draw a bitmap with the result points highlighted instead of the live
* scanning display.
*
* @param barcode
* An image of the decoded barcode.
*/
public void drawResultBitmap(Bitmap barcode) {
resultBitmap = barcode;
invalidate();
}
public void addPossibleResultPoint(ResultPoint point) {
possibleResultPoints.add(point);
}
}
上面的代码中，中间那根线微信是用的图片，我这里是画的，如果你想更加仿真点就将下面的代码
canvas.drawRect(frame.left + MIDDLE_LINE_PADDING, slideTop - MIDDLE_LINE_WIDTH/2, frame.right - MIDDLE_LINE_PADDING,slideTop + MIDDLE_LINE_WIDTH/2, paint);
改成
Rect lineRect = new Rect();
lineRect.left = frame.left;
lineRect.right = frame.right;
lineRect.top = slideTop;
lineRect.bottom = slideTop + 18;
canvas.drawBitmap(((BitmapDrawable)(getResources().getDrawable(R.drawable.qrcode_scan_line))).getBitmap(), null, lineRect, paint);
那条扫描线自己去微信里面找一下，我贴出来的失真了，下载微信apk,将后缀名改成zip,然后解压就行了
画扫描框下面字体的代码需要修改下，这样子能根据字体自动排列在中间，如果字太长我没有处理，那个要自动换行，你可以自行处理
paint.setColor(Color.WHITE); paint.setTextSize(TEXT_SIZE * density); paint.setAlpha(0x40); paint.setTypeface(Typeface.DEFAULT_BOLD); String text = getResources().getString(R.string.R.string.scan_text); float textWidth = paint.measureText(text); canvas.drawText(text, (width - textWidth)/2, (float) (frame.bottom + (float)TEXT_PADDING_TOP *density), paint)
运行界面截图，其中中间的那根绿色的线会上下移动，跟微信的效果差不多，当然运行你还需要相对应的权限问题。
以上就是本文的全部内容，希望对大家学习Android软件编程有所帮助。
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