Android Calculator maker 2. Register the View build function

I am new to the whole two days to finally get the fix.

1. First, register in the OnCreate function in mainactivity

2. Press the + or-sign to divide into two large strings S1 and S2

Then divide the S2 into smaller s1 and S2 until S2 does not contain a + or-No.

The idea is this, no recursion, recursive speed is too slow, also not good at recursion.

3. is to find a variety of bugs and decorations

Basically achieve the goal and your own mobile phone on Android's own calculator basically the same.

The project code is as follows:

Link: Link: http://pan.baidu.com/s/1sj65nop Password: 926r

See also use Baidu cloud know I have many dishes ...

The wording is as follows:

Package Com.example.administrator.myapplication;import Android.app.activity;import Android.support.v7.app.appcompatactivity;import Android.os.bundle;import Android.util.log;import Android.view.menu;import Android.view.menuitem;import Android.view.view;import Android.view.View.OnClickListener; Import Android.widget.button;import Android.widget.edittext;public class Mainactivity extends Activity implements    Onclicklistener {private Button bt_0;    Private Button bt_1;    Private Button bt_2;    Private Button bt_3;    Private Button Bt_4;    Private Button bt_5;    Private Button bt_6;    Private Button bt_7;    Private Button bt_8;    Private Button Bt_9;    Private Button Bt_point;    Private Button Bt_c;    Private Button Bt_del;    Private Button Bt_minuse;    Private Button bt_multipy;    Private Button Bt_plus;    Private Button bt_divide;    Private Button Bt_dengyu;    Private EditText Input_text; @Override protected void OnCreate (Bundle savedinstancestate) {Super. OnCreate (Savedinstancestate);        Setcontentview (R.layout.activity_main);//Register button BT_0 = (button) Findviewbyid (R.ID.BT_0);        Bt_1 = (Button) Findviewbyid (r.id.bt_1);        Bt_2 = (Button) Findviewbyid (r.id.bt_2);        Bt_3 = (Button) Findviewbyid (r.id.bt_3);        Bt_4 = (Button) Findviewbyid (r.id.bt_4);        Bt_5 = (Button) Findviewbyid (r.id.bt_5);        Bt_6 = (Button) Findviewbyid (r.id.bt_6);        bt_7 = (Button) Findviewbyid (r.id.bt_7);        Bt_8 = (Button) Findviewbyid (r.id.bt_8);        Bt_9 = (Button) Findviewbyid (r.id.bt_9);        Bt_point = (Button) Findviewbyid (r.id.bt_point);        Bt_c = (Button) Findviewbyid (r.id.bt_clear);        Bt_del = (Button) Findviewbyid (R.id.bt_del);        Bt_minuse = (Button) Findviewbyid (r.id.bt_minuse);        bt_multipy = (Button) Findviewbyid (r.id.bt_multipy);        Bt_plus = (Button) Findviewbyid (R.id.bt_plus);        Bt_divide = (Button) Findviewbyid (r.id.bt_divide); Bt_dengyu = (Button) findviEwbyid (R.id.bt_dengyu);        Input_text = (EditText) Findviewbyid (R.ID.EDIT_TEXT1);//Listener Event Bt_0.setonclicklistener (this);        Bt_1.setonclicklistener (this);        Bt_2.setonclicklistener (this);        Bt_3.setonclicklistener (this);        Bt_4.setonclicklistener (this);        Bt_5.setonclicklistener (this);        Bt_6.setonclicklistener (this);        Bt_7.setonclicklistener (this);        Bt_8.setonclicklistener (this);        Bt_9.setonclicklistener (this);        Bt_point.setonclicklistener (this);        Bt_c.setonclicklistener (this);        Bt_del.setonclicklistener (this);        Bt_minuse.setonclicklistener (this);        Bt_multipy.setonclicklistener (this);        Bt_plus.setonclicklistener (this);        Bt_divide.setonclicklistener (this);    Bt_dengyu.setonclicklistener (this); } @Override Public boolean Oncreateoptionsmenu (Menu menu) {//Inflate the menu, this adds items to the Actio        n Bar if it is present. Getmenuinflater (). Inflate (R.menu. Menu_main, menu);    return true; } @Override public boolean onoptionsitemselected (MenuItem Item) {//Handle Action Bar item clicks here.  The action bar would//automatically handle clicks on the Home/up button, so long/As you specify a parent        Activity in Androidmanifest.xml.        int id = item.getitemid ();        Noinspection simplifiableifstatement if (id = = r.id.action_settings) {return true;    } return super.onoptionsitemselected (item);        } @Override public void OnClick (View v) {String str = Input_text.gettext (). toString (); Switch (V.getid ()) {case R.id.bt_0:case r.id.bt_1:case r.id.bt_2:case r.id            . bt_3:case r.id.bt_4:case r.id.bt_5:case r.id.bt_6:case r.id.bt_7:               Case R.id.bt_8:case R.id.bt_9:input_text.settext (str + (Button) v). GetText ()); Break                Case R.id.bt_point:if (!str.contains (".")) Input_text.settext (str + (button) v). GetText ());            Break                Case R.id.bt_plus:case r.id.bt_minuse:case r.id.bt_multipy:case r.id.bt_divide:                if (Str.equals (""));                    else {char a =str.charat (Str.length ()-1);                    LOG.I ("str", str+ "");                    LOG.I ("Last character", A + "");                    if (a = = ");                    else {input_text.settext (str + "" + (Button) v). GetText () + "");                    } A =str.charat (Str.length ()-1);                Break            } break;                Case R.id.bt_clear:input_text.settext (NULL);            Break Case R.id.bt_del:if (str! = null &&!str.equals ("")) {Input_text.settext (STR.S Ubstring (0, Str.length()-1));            } break;                Case R.id.bt_dengyu:getrseult ();        Break        }}//operation result private void Getrseult () {String str = Input_text.gettext (). toString ();        if (str = = NULL | | str.equals (")") return; if (!str.contains ("+") &&!str.contains ("-") &&!str.contains ("X") &&!str.contains ("+")) re        Turn        Traverse computed result double result = 0;        Char a =str.charat (Str.length ()-2);        if (A = = ' + ' | | a = = '-') {str = str + ' 0 ';        } else if (a = = ' X ' | | a = = ' ÷ ') {str = str + ' 1 ';        } int i = 0;        int start = 0;        char temp = ';        int flag = 1;        if (!str.contains ("+") &&!str.contains ("-")) {result + = Calculate_include_multy_or_minuse (str);                } else {for (; I < str.length (); i++) {char c = str.charat (i); if (c = = ' + ' | |                    c = = '-') {String S1 = str.substring (start, i);                    LOG.I ("S1 is", S1 + "");                    if (flag = = 0) Result-= Calculate_include_multy_or_minuse (S1);                    else result + = Calculate_include_multy_or_minuse (S1);                    start = i + 1;                    if (c = = '-') flag = 0;                    else flag = 1;                    String s2 = str.substring (Start, str.length ());                    LOG.I ("S2 is", S2 + "");                        if (S2.contains ("+") | | | s2.contains ("-")) {temp = C;                    Continue } else {if (flag = = 0) {Result-= Calculate_include_                        Multy_or_minuse (S2);                    } else result + = Calculate_include_multy_or_minuse (s2); }}}} int r = 0;//String result_string = DOuble.tostring (result);            if ((int) result = = result) {R = (int) result;        Input_text.settext (R + "");    } else Input_text.settext (Result + "");        } private double Calculate (String s) {double sum = 1;        int start = 0;        int flag = 0;        int flag2 = 0;        s = s + ' x ';        char op = ';            for (int i = 0; i < s.length (); i++) {char c = s.charat (i);                if (c = = ' X ' | | c = = ' ÷ ') {if (Flag2 = = 0) op = c;                String S1 = s.substring (start, i);                    if (flag = = 0) {sum *= double.parsedouble (S1);//LOG.I ("First is", "" +sum);                    flag = 1;                Flag2 = 1; } else {switch (OP) {case ' X '://LOG.I ("S1 is", "" "+s1                            ); sum = sum * double.parsedouble (S1);//LOG.I ("Sum is "," "+sum";                        Break                            Case ' ÷ '://LOG.I ("S2 is", "" +s1);                            sum = sum/double.parsedouble (S1);//LOG.I ("Sum is", "" +sum);                    Break                }} op = C;            start = i + 1;        }}//log.i ("The result of Sum is", "" + sum);    return sum;                } private double Calculate_include_multy_or_minuse (String s) {double sum = 0;                if (S.contains ("x") | | | s.contains ("÷")) {sum = calculate (s);                } else {sum = double.parsedouble (s);    } return sum; }}

　　

　　

Android Calculator maker 2. Register the View build function