編輯:關於Android編程
由於項目中要用到驗證碼,自己找了些資料,試著就把這個驗證碼給做了出來,代碼不是很多,比較的簡單,下面給大家看看我是怎麼實現該功能的:
首先當然是寫XML咯,貼上代碼
下面貼一下MainActivity的代碼:
裡面的注釋很詳細,就不多說了!
import android.os.Bundle; import android.app.Activity; import android.util.Log; import android.view.Menu; 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 { ImageView vc_image; //圖標 Button vc_shuaixi,vc_ok; //確定和刷新驗證碼 String getCode=null; //獲取驗證碼的值 EditText vc_code; //文本框的值 @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); vc_image=(ImageView)findViewById(R.id.vc_image); vc_image.setImageBitmap(Code.getInstance().getBitmap()); vc_code=(EditText) findViewById(R.id.vc_code); getCode=Code.getInstance().getCode(); //獲取顯示的驗證碼 Log.e(info, getCode+----); vc_shuaixi=(Button)findViewById(R.id.vc_shuaixi); vc_shuaixi.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { // TODO Auto-generated method stub vc_image.setImageBitmap(Code.getInstance().getBitmap()); getCode=Code.getInstance().getCode(); } }); vc_ok=(Button)findViewById(R.id.vc_ok); vc_ok.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { // TODO Auto-generated method stub String v_code=vc_code.getText().toString().trim(); if(v_code==null||v_code.equals()){ Toast.makeText(MainActivity.this, 沒有填寫驗證碼, 2).show(); }else if(!v_code.equals(getCode)){ Toast.makeText(MainActivity.this, 驗證碼填寫不正確, 2).show(); }else{ Toast.makeText(MainActivity.this, 操作成功, 2).show(); } } }); }
最後貼一下做驗證碼必須的一個類Code:
import java.util.Random; import android.graphics.Bitmap; import android.graphics.Canvas; import android.graphics.Color; import android.graphics.Paint; import android.graphics.Bitmap.Config; public class Code { 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 Code bpUtil; private Code(){}; public static Code getInstance() { if(bpUtil == null) bpUtil = new Code(); return bpUtil; } //default settings private static final int DEFAULT_CODE_LENGTH = 4;//驗證碼的長度 這裡是4位 private static final int DEFAULT_FONT_SIZE = 60;//字體大小 private static final int DEFAULT_LINE_NUMBER = 3;//多少條干擾線 private static final int BASE_PADDING_LEFT = 20; //左邊距 private static final int RANGE_PADDING_LEFT = 35;//左邊距范圍值 private static final int BASE_PADDING_TOP = 42;//上邊距 private static final int RANGE_PADDING_TOP = 15;//上邊距范圍值 private static final int DEFAULT_WIDTH = 200;//默認寬度.圖片的總寬 private static final int DEFAULT_HEIGHT = 70;//默認高度.圖片的總高 private final int DEFAULT_COLOR=0xdf;//默認背景顏色值 //settings decided by the layout xml //canvas width and height private int width = DEFAULT_WIDTH; private int height = DEFAULT_HEIGHT; //random word space and pading_top private int base_padding_left = BASE_PADDING_LEFT; private int range_padding_left = RANGE_PADDING_LEFT; private int base_padding_top = BASE_PADDING_TOP; private int range_padding_top = RANGE_PADDING_TOP; //number of chars, lines; font size private int codeLength = DEFAULT_CODE_LENGTH; private int line_number = DEFAULT_LINE_NUMBER; private int font_size = DEFAULT_FONT_SIZE; //variables private String code;//保存生成的驗證碼 private int padding_left, padding_top; private Random random = new Random(); private Bitmap createBitmap() { padding_left = 0; Bitmap bp = Bitmap.createBitmap(width, height, Config.ARGB_8888); Canvas c = new Canvas(bp); code = createCode(); c.drawColor(Color.rgb(DEFAULT_COLOR, DEFAULT_COLOR, DEFAULT_COLOR)); Paint paint = new Paint(); paint.setTextSize(font_size); for (int i = 0; i < code.length(); i++) { randomTextStyle(paint); randomPadding(); c.drawText(code.charAt(i) + , padding_left, padding_top, paint); } for (int i = 0; i < line_number; i++) { drawLine(c, paint); } c.save( Canvas.ALL_SAVE_FLAG );//保存 c.restore();// return bp; } public String getCode() { return code.toLowerCase(); } public Bitmap getBitmap(){ return createBitmap(); } private String createCode() { StringBuilder buffer = new StringBuilder(); for (int i = 0; i < codeLength; i++) { buffer.append(CHARS[random.nextInt(CHARS.length)]); } return buffer.toString(); } private void drawLine(Canvas canvas, Paint paint) { int color = randomColor(); int startX = random.nextInt(width); int startY = random.nextInt(height); int stopX = random.nextInt(width); int stopY = random.nextInt(height); paint.setStrokeWidth(1); paint.setColor(color); canvas.drawLine(startX, startY, stopX, stopY, paint); } private int randomColor() { return randomColor(1); } private int randomColor(int rate) { int red = random.nextInt(256) / rate; int green = random.nextInt(256) / rate; int blue = random.nextInt(256) / rate; return Color.rgb(red, green, blue); } private void randomTextStyle(Paint paint) { int color = randomColor(); paint.setColor(color); paint.setFakeBoldText(random.nextBoolean()); //true為粗體,false為非粗體 float skewX = random.nextInt(11) / 10; skewX = random.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為下劃線,false為非下劃線 // paint.setStrikeThruText(true); //true為刪除線,false為非刪除線 } private void randomPadding() { padding_left += base_padding_left + random.nextInt(range_padding_left); padding_top = base_padding_top + random.nextInt(range_padding_top); } }
代碼已經貼完畢,可以試著做一下!
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