第一步activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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=".MainActivity">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginLeft="10dp"
android:orientation="vertical">
<ImageView
android:id="@+id/image"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:src="@drawable/a"/>
<EditText
android:id="@+id/et"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:hint="輸入驗證碼"/>
<Button
android:id="@+id/btn"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:text="獲得驗證碼"/>
<Button
android:id="@+id/btn_submit"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:text="提交"/>
</LinearLayout>
</RelativeLayout>
第二步 新建CodeUtils類
package com.example.myncode;
import android.graphics.Bitmap;
import android.graphics.Bitmap.Config;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import java.util.Random;
/**
* Created by yao
* 用於圖片驗證碼的工具類
*/
public class CodeUtils {
private static final char[] CHARS = {
'0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm',
'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z',
'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M',
'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z'
};
private static CodeUtils mCodeUtils;
private int mPaddingLeft, mPaddingTop;
private StringBuilder mBuilder = new StringBuilder();
private Random mRandom = new Random();
//Default Settings
private static final int DEFAULT_CODE_LENGTH = 6;//驗證碼的長度 這裏是6位
private static final int DEFAULT_FONT_SIZE = 60;//字體大小
private static final int DEFAULT_LINE_NUMBER = 3;//多少條幹擾線
private static final int BASE_PADDING_LEFT = 20; //左邊距
private static final int RANGE_PADDING_LEFT = 30;//左邊距範圍值
private static final int BASE_PADDING_TOP = 70;//上邊距
private static final int RANGE_PADDING_TOP = 15;//上邊距範圍值
private static final int DEFAULT_WIDTH = 300;//默認寬度.圖片的總寬
private static final int DEFAULT_HEIGHT = 100;//默認高度.圖片的總高
private static final int DEFAULT_COLOR = 0xDF;//默認背景顏色值
private String code;
public static CodeUtils getInstance() {
if(mCodeUtils == null) {
mCodeUtils = new CodeUtils();
}
return mCodeUtils;
}
//生成驗證碼圖片
public Bitmap createBitmap() {
mPaddingLeft = 0; //每次生成驗證碼圖片時初始化
mPaddingTop = 0;
Bitmap bitmap = Bitmap.createBitmap(DEFAULT_WIDTH, DEFAULT_HEIGHT, Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);
code = createCode();
canvas.drawColor(Color.rgb(DEFAULT_COLOR, DEFAULT_COLOR, DEFAULT_COLOR));
Paint paint = new Paint();
paint.setTextSize(DEFAULT_FONT_SIZE);
for (int i = 0; i < code.length(); i++) {
randomTextStyle(paint);
randomPadding();
canvas.drawText(code.charAt(i) + "" , mPaddingLeft, mPaddingTop, paint);
}
//干擾線
for (int i = 0; i < DEFAULT_LINE_NUMBER; i++) {
drawLine(canvas, paint);
}
// canvas.save(Canvas.ALL_SAVE_FLAG);//保存
canvas.save();//保存
canvas.restore();
return bitmap;
}
/**
* 得到圖片中的驗證碼字符串
* @return
*/
public String getCode() {
return code;
}
//生成驗證碼
public String createCode() {
mBuilder.delete(0, mBuilder.length()); //使用之前首先清空內容
for (int i = 0; i < DEFAULT_CODE_LENGTH; i++) {
mBuilder.append(CHARS[mRandom.nextInt(CHARS.length)]);
}
return mBuilder.toString();
}
//生成干擾線
private void drawLine(Canvas canvas, Paint paint) {
int color = randomColor();
int startX = mRandom.nextInt(DEFAULT_WIDTH);
int startY = mRandom.nextInt(DEFAULT_HEIGHT);
int stopX = mRandom.nextInt(DEFAULT_WIDTH);
int stopY = mRandom.nextInt(DEFAULT_HEIGHT);
paint.setStrokeWidth(1);
paint.setColor(color);
canvas.drawLine(startX, startY, stopX, stopY, paint);
}
//隨機顏色
private int randomColor() {
mBuilder.delete(0, mBuilder.length()); //使用之前首先清空內容
String haxString;
for (int i = 0; i < 3; i++) {
haxString = Integer.toHexString(mRandom.nextInt(0xFF));
if (haxString.length() == 1) {
haxString = "0" + haxString;
}
mBuilder.append(haxString);
}
return Color.parseColor("#" + mBuilder.toString());
}
//隨機文本樣式
private void randomTextStyle(Paint paint) {
int color = randomColor();
paint.setColor(color);
paint.setFakeBoldText(mRandom.nextBoolean()); //true爲粗體,false爲非粗體
float skewX = mRandom.nextInt(11) / 10;
skewX = mRandom.nextBoolean() ? skewX : -skewX;
paint.setTextSkewX(skewX); //float類型參數,負數表示右斜,整數左斜
// paint.setUnderlineText(true); //true爲下劃線,false爲非下劃線
// paint.setStrikeThruText(true); //true爲刪除線,false爲非刪除線
}
//隨機間距
private void randomPadding() {
mPaddingLeft += BASE_PADDING_LEFT + mRandom.nextInt(RANGE_PADDING_LEFT);
mPaddingTop = BASE_PADDING_TOP + mRandom.nextInt(RANGE_PADDING_TOP);
}
}
第三步MainActivity.java
package com.example.myncode;
import android.app.Activity;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.text.TextUtils;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.Toast;
public class MainActivity extends Activity implements OnClickListener {
private ImageView image;
private EditText et;
private Button btn,submit;
private String codeStr;
private CodeUtils codeUtils;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initView();
}
private void initView() {
image = (ImageView) findViewById(R.id.image);
et = (EditText) findViewById(R.id.et);
btn = (Button) findViewById(R.id.btn);
submit = (Button) findViewById(R.id.btn_submit);
btn.setOnClickListener(this);
submit.setOnClickListener(this);
}
@Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.btn:
codeUtils = CodeUtils.getInstance();
Bitmap bitmap = codeUtils.createBitmap();
image.setImageBitmap(bitmap);
break;
case R.id.btn_submit:
codeStr = et.getText().toString().trim();
Log.e("codeStr", codeStr);
if (null == codeStr || TextUtils.isEmpty(codeStr)) {
Toast.makeText(this, "請輸入驗證碼", 0).show();
return;
}
String code = codeUtils.getCode();
Log.e("code", code);
if (code.equalsIgnoreCase(codeStr)) {
Toast.makeText(this, "驗證碼正確", 0).show();
} else {
Toast.makeText(this, "驗證碼錯誤", 0).show();
}
break;
default:
break;
}
}
}
第四步在drawable添加圖片