Implementation of random verification code generated by Android client

because the project to use the verification code, I found some information, try to put this verification code to do out, the code is not many, the comparison is simple, the following to see how I realize the function:

Source Address Download : http://download.csdn.net/detail/u014608640/7268905

First of all, of course, write the XML, put the code

 <linearlayout android:layout_width= "match_parent" android:layout_height= "Wrap_content" Android:orie           ntation= "Horizontal" android:id= "@+id/yh" > <textview android:text= "username:" Android:layout_width= "Wrap_content" android:layout_height= "wrap_content"/> <ed          Ittext android:layout_width= "fill_parent" android:layout_height= "Wrap_content"/> </LinearLayout> <linearlayout android:layout_width= "Match_parent" Android:layout_heigh       t= "wrap_content" android:orientation= "horizontal" android:layout_below= "@id/yh" android:id= "@+id/pwd" > <textview android:text= "Password:" android:layout_width= "Wrap_content" a ndroid:layout_height= "Wrap_content"/> <edittext android:layout_width= "fill_parent "Android:layout_height= "Wrap_content"/> </LinearLayout> <linearlayout android:layou T_width= "Match_parent" android:layout_height= "wrap_content" android:gravity= "center_vertical "Android:layout_margintop=" 4DP "android:orientation=" Horizontal "android:lay                    out_below= "@id/pwd" android:id= "@+id/code" > <linearlayout Android:layout_width= "Wrap_content" android:layout_height= "Wrap_content" and Roid:layout_marginbottom= "10DP" android:layout_marginleft= "10DP" Android:layout_marg                    inright= "10DP" android:layout_margintop= "5DP" android:orientation= "Horizontal" > <textview android:layout_width= "Wrap_content" Android: Layout_height= "Wrap_contEnt "android:layout_marginleft=" 20DP "android:layout_marginright=" 5DP " android:text= "Verification Code:" Android:textcolor= "#000000"/> <ed                        Ittext android:id= "@+id/vc_code" android:layout_width= "60DP" android:layout_height= "Wrap_content" android:layout_weight= "1" Andro                        Id:background= "#0000" android:maxlength= "4" android:paddingbottom= "10DP" android:paddingleft= "10DP" android:paddingtop= "10DP" and                Roid:textcolor= "#000000" android:textsize= "14sp"/> </LinearLayout>                     <imageview android:id= "@+id/vc_image" android:layout_width= "Wrap_content" Androidoid:layout_height= "Match_parent" android:layout_marginbottom= "10DP" android:layout_m argintop= "5DP" android:layout_weight= "1"/> <button android:id=                    "@+id/vc_shuaixi" android:layout_width= "40DP" android:layout_height= "Wrap_content" Android:background= "@android: Color/transparent" android:layout_gravity= "center_vertic Al "android:text=" Refresh Captcha "android:textstyle=" Italic "android:layou                     t_margintop= "5DP" android:layout_marginbottom= "10DP" android:layout_marginleft= "5DP" android:layout_marginright= "5DP" android:textcolor= "#7f7f7f" and Roid:textsize= "12SP"/> </LinearLayout> <linearlayout android:layout_width= "Match_paren T "Android:layout_height= "Wrap_content" android:layout_below= "@id/code" android:orientation= "Horizontal" > <Bu Tton android:id= "@+id/vc_ok" android:layout_width= "match_parent" android:layout_height= "Wra P_content "android:text=" OK "/> </LinearLayout>

Here's the code for Mainactivity:

The inside of the note is very detailed, not much to say!

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;//Icon Button VC_SHUAIXI,VC_OK;//Confirm and refresh Captcha String getcode=null;//Get Verification code value EditText Vc_code; The value of the text box @overrideprotected 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 (); Get the verification code shown LOG.E ("info", getcode+ "----"); vc_shuaixi= (Button) Findviewbyid (R.id.vc_shuaixi); vc_ Shuaixi.setonclicklistener (New Onclicklistener () {@Overridepublic void OnClick (View v) {//TODO auto-generated method StubvC_image.setimagebitmap (Code.getinstance (). Getbitmap ()); Getcode=code.getinstance (). GetCode ();}); vc_ok= (Button) Findviewbyid (R.ID.VC_OK); Vc_ok.setonclicklistener (new Onclicklistener () {@Overridepublic void OnClick (View v) {//TODO auto-generated Method Stubstringv_code=vc_code.gettext (). toString (). Trim (); if (v_code==null| | V_code.equals (")) {Toast.maketext (" ") {mainactivity.this," No verification Code entered ", 2). Show (); else if (!v_code.equals (GetCode)) {Toast.maketext (Mainactivity.this, "The verification code is not filled in correctly", 2). Show (); Else{toast.maketext (Mainactivity.this, "Operation succeeded", 2). Show ();}});}

Finally, one of the classes required for CAPTCHA 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 '};p rivate static Code b Putil;private code () {};p ublic static code getinstance () {if (Bputil = = null) Bputil = new Code (); return bputil;} Default settingsprivate static final int default_code_length = 4;//The length of the verification code here is the 4 bit private static final int default_font_si ZE = 60;//Font size private static final int default_line_number = 3;//How many lines of interference private static final int base_padding_left = 20; Left margin private static final int range_padding_left = 35;//Left margin range value private staticFinal int base_padding_top = 42;//Top margin private static final int range_padding_top = 15;//Top margin range value private static final int DEFA Ult_width = 200;//default width. The total width of the picture private static final int default_height = 70;//default height. Total height of the picture private final int default_color=0xdf ;//default background color value//settings decided by the layout xml//canvas width and heightprivate int width = default_width;private int Heigh t = default_height; Random word space and pading_topprivate 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 sizeprivate int codelength = default_code_length;private int line_number = default_line_number;private int font_size = Default_font_size;//variablesprivate String code;//Save generated verification code private int Padding_left, padding_top;private Random Random = new Random ();p rivate 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 ();p aint.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);//Save 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.ap Pend (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);p aint.setstrokewidth (1) ;p aint.SetColor (color); Canvas.drawline (StartX, Starty, stopx, stopy, paint);} private int Randomcolor () {return randomcolor (1);} private int Randomcolor (int rate) {int red = random.nextint/Rate;int green = Random.nextint (in)/rate;int blue = Random.nextint (Rate;return)/Color.rgb (red, green, blue);} private void Randomtextstyle (paint paint) {int color = Randomcolor ();p aint.setcolor (color);p Aint.setfakeboldtext (  Random.nextboolean ()); True is bold, false is non-bold float skewx = Random.nextint (one-by-one)/10;skewx = Random.nextboolean ()? SKEWX:-skewx;paint.settextskewx (SKEWX); Float type parameter, negative number indicates right oblique, integer left oblique//paint.setunderlinetext (true); True to underline, false to non-underscore//paint.setstrikethrutext (true); True for strikethrough, false for non-strikethrough}private void randompadding () {padding_left + = Base_padding_left + random.nextint (range_padding_ left);p adding_top = Base_padding_top + random.nextint (range_padding_top);}}

The code has been posted, you can try to do it!