Android實現房貸計算器
本文實例為大傢分享瞭Android實現房貸計算器的具體代碼,供大傢參考,具體內容如下
fangdai(activity)
package com.example.myapplication_one; import android.os.Bundle; import android.support.v7.app.AppCompatActivity; import android.text.Editable; import android.text.TextUtils; import android.text.TextWatcher; import android.view.View; import android.widget.ArrayAdapter; import android.widget.Button; import android.widget.CheckBox; import android.widget.EditText; import android.widget.RadioGroup; import android.widget.Spinner; import android.widget.TextView; import android.widget.Toast; public class fangdai extends AppCompatActivity { //聲明用到的所有控件 Spinner spinner1; Spinner spinner2; EditText row1edit; EditText row2edit; Button total; RadioGroup radioGroup; CheckBox checkBox1; CheckBox checkBox2; EditText row4edit; EditText row5edit; Button detail; TextView totalcal; TextView alldetail; private void initSpinner(){ //初始化控件 spinner1= (Spinner) findViewById(R.id.sp1); spinner2= (Spinner) findViewById(R.id.sp2); //建立數據源 String[] years=getResources().getStringArray(R.array.years); String[] baserates=getResources().getStringArray(R.array.baserate); //聲明一個下拉列表的數組適配器並綁定數據源 ArrayAdapter<String> yearAdapter=new ArrayAdapter<String>(this,R.layout.support_simple_spinner_dropdown_item,years); ArrayAdapter<String> baserateAdapter=new ArrayAdapter<String>(this,R.layout.support_simple_spinner_dropdown_item,baserates); //綁定Adapter到控件 spinner1.setAdapter(yearAdapter); spinner2.setAdapter(baserateAdapter); //設置默認選擇第一項 spinner1.setSelection(0); spinner2.setSelection(0); //設置標題 spinner1.setPrompt("請選擇貸款年限"); spinner2.setPrompt("請選擇基準利率"); } //聲明下列函數中要用到的變量 double intotal,backtotal,extra,pertime;//貸款總額,還款總額,利息,每月還款總額 int month;//月份 String buytotal;//購房總額 String percent;//貸款百分比 @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.fangdai); //初始化控件 initSpinner(); row1edit= (EditText) findViewById(R.id.row1edit); row2edit= (EditText) findViewById(R.id.row2edit); total= (Button) findViewById(R.id.totalcal); radioGroup= (RadioGroup) findViewById(R.id.radiogroup); checkBox1= (CheckBox) findViewById(R.id.check1); checkBox2= (CheckBox) findViewById(R.id.check2); totalcal= (TextView) findViewById(R.id.showtotal); detail= (Button) findViewById(R.id.detail); alldetail= (TextView) findViewById(R.id.alldetail); row4edit= (EditText) findViewById(R.id.row4label); row5edit= (EditText) findViewById(R.id.row5label); //給第一個計算按鈕添加點擊監聽 total.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { buytotal=row1edit.getText().toString(); percent=row2edit.getText().toString(); if(TextUtils.isEmpty(buytotal)||TextUtils.isEmpty(percent))//判斷前兩個輸入框是否非空 { Toast.makeText(fangdai.this,"購房總價和按揭部分信息填寫完整",Toast.LENGTH_LONG).show(); }else if(fangdaitext.isNum(buytotal)==false||fangdaitext.isNum(percent)==false){//判斷輸入的是否是數字 Toast.makeText(fangdai.this,"包含不合法的輸入信息",Toast.LENGTH_LONG).show(); } else if(Double.parseDouble(percent)>100){//判斷百分比部分輸入是否大於100% Toast.makeText(fangdai.this,"按揭部分不能超過100%",Toast.LENGTH_LONG).show(); } else if(fangdaitext.isNum(buytotal)&&fangdaitext.isNum(percent)) { intotal=(Double.parseDouble(buytotal)*Double.parseDouble(percent)*0.01); totalcal.setText("您的貸款總額為"+String.format("%.2f",intotal)+"萬元"); } } }); detail.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { //first,second為商貸和公積金貸所填數值 String first=row4edit.getText().toString(); String second=row5edit.getText().toString(); //firstrate和secondrate為商貸和公積金的年利率 double firstrate=Double.parseDouble(spinner2.getSelectedItem().toString().substring(20,24))*0.01; double secondrate=Double.parseDouble(spinner2.getSelectedItem().toString().substring(31,35))*0.01; //獲取下拉列表的年份求得月份 String year=spinner1.getSelectedItem().toString(); month=Integer.parseInt(year.substring(0,year.length()-1))*12; //兩種貸款的月利率 double firstmonthrate=firstrate/12; double secondmonthrate=secondrate/12; if(totalcal.getText().toString().equals("其中貸款部分為:***萬")){//判斷是否計算過貸款總額 Toast.makeText(fangdai.this,"請先計算貸款總額",Toast.LENGTH_LONG).show(); }else if(row1edit.getText().toString().equals(buytotal)==false||row2edit.getText().toString().equals(percent)==false){//監聽貸款總額和按揭部分數值是否發生變化 Toast.makeText(fangdai.this,"檢查到您的購房總價或按揭部分數據更改,請重新計算貸款總額",Toast.LENGTH_LONG).show(); } else if(checkBox1.isChecked()==false&&checkBox2.isChecked()==false)//監聽勾選的多選框 { Toast.makeText(fangdai.this,"請勾選貸款種類",Toast.LENGTH_LONG).show(); }else if(checkBox1.isChecked()&&checkBox2.isChecked()==false){ //等額本息貸款算法 if(radioGroup.getCheckedRadioButtonId()==R.id.btn1){ pertime=intotal*firstmonthrate*Math.pow((1+firstmonthrate),month)/(Math.pow(1+firstmonthrate,month)-1); backtotal=pertime*month; extra=backtotal-intotal; alldetail.setText("您的貸款總額為"+String.format("%.2f",intotal)+"萬元\n還款總額為"+String.format("%.2f",backtotal)+"萬元\n其中利息總額為"+String.format("%.2f",extra)+"萬元\n還款總時間為"+month+"月\n每月還款金額為"+String.format("%.2f",pertime*10000)+"元"); }else{//等額本金貸款算法 double[] array=new double[month]; double sum=0; for(int i=0;i<month;i++) { array[i]=intotal/month+(intotal-sum)*firstmonthrate; sum+=array[i]; } String text=""; for(int i=0;i<month;i++){ text+="\n第"+(i+1)+"個月應還金額為:"+String.format("%.2f",array[i]*10000); } backtotal=sum; extra=backtotal-intotal; alldetail.setText("您的貸款總額為"+String.format("%.2f",intotal)+"萬元\n還款總額為"+String.format("%.2f",backtotal)+"萬元\n其中利息總額為"+String.format("%.2f",extra)+"萬元\n還款總時間為"+month+"月\n每月還款金額如下:"+text); } }else if(checkBox1.isChecked()==false&&checkBox2.isChecked()){ if(radioGroup.getCheckedRadioButtonId()==R.id.btn1){ pertime=intotal*secondmonthrate*Math.pow((1+secondmonthrate),month)/(Math.pow(1+secondmonthrate,month)-1); backtotal=pertime*month; extra = backtotal - intotal; alldetail.setText("您的貸款總額為" + String.format("%.2f",intotal) + "萬元\n還款總額為"+String.format("%.2f",backtotal)+"萬元\n其中利息總額為"+String.format("%.2f",extra)+"萬元\n還款總時間為"+month+"月\n每月還款金額為"+String.format("%.2f",pertime*10000)+"元"); }else{ double[] array=new double[month]; double sum=0; for(int i=0;i<month;i++) { array[i]=intotal/month+(intotal-sum)*secondmonthrate; sum+=array[i]; } String text=""; for(int i=0;i<month;i++){ text+="\n第"+(i+1)+"個月應還金額為:"+String.format("%.2f",array[i]*10000)+"元"; } backtotal=sum; extra=backtotal-intotal; alldetail.setText("您的貸款總額為"+String.format("%.2f",intotal)+"萬元\n還款總額為"+String.format("%.2f",backtotal)+"萬元\n其中利息總額為"+String.format("%.2f",extra)+"萬元\n還款總時間為"+month+"月\n每月還款金額如下:"+text); } }else if(checkBox1.isChecked()&&checkBox2.isChecked()){ if(radioGroup.getCheckedRadioButtonId()==R.id.btn1){ if(TextUtils.isEmpty(first)||TextUtils.isEmpty(second)){ Toast.makeText(fangdai.this,"請將空信息填寫完整",Toast.LENGTH_LONG).show(); }else if(fangdaitext.isNum(first)==false||fangdaitext.isNum(second)==false){ Toast.makeText(fangdai.this,"包含不合法的輸入信息",Toast.LENGTH_LONG).show(); }else if(Double.parseDouble(first)+Double.parseDouble(second)!=Double.parseDouble(String.format("%.2f",intotal))){ Toast.makeText(fangdai.this,"填寫的兩項貸款總額不等於初始貸款額度,請重新填寫",Toast.LENGTH_LONG).show(); }else{ double p1=Double.parseDouble(first); double p2=Double.parseDouble(second); double pertime1=p1*firstmonthrate*Math.pow((1+firstmonthrate),month)/(Math.pow(1+firstmonthrate,month)-1); double pertime2=p2*secondmonthrate*Math.pow((1+secondmonthrate),month)/(Math.pow(1+secondmonthrate,month)-1); pertime=pertime1+pertime2; backtotal=pertime*month; extra=backtotal-intotal; alldetail.setText("您的貸款總額為" + String.format("%.2f",intotal) + "萬元\n還款總額為"+String.format("%.2f",backtotal)+"萬元\n其中利息總額為"+String.format("%.2f",extra)+"萬元\n還款總時間為"+month+"月\n每月還款金額為"+String.format("%.2f",pertime*10000)+"元"); } }else{ if(first.equals("請輸入商業貸款總額(單位萬)")||second.equals("請輸入公積金貸款總額(單位萬)")){ Toast.makeText(fangdai.this,"請將空信息填寫完整",Toast.LENGTH_LONG).show(); }else if(fangdaitext.isNum(first)==false||fangdaitext.isNum(second)==false){ Toast.makeText(fangdai.this,"包含不合法的輸入信息",Toast.LENGTH_LONG).show(); }else if(Double.parseDouble(first)+Double.parseDouble(second)!=Double.parseDouble(String.format("%.2f",intotal))){ Toast.makeText(fangdai.this,"填寫的兩項貸款總額不等於初始貸款額度,請重新填寫",Toast.LENGTH_LONG).show(); }else{ double p1=Double.parseDouble(first); double p2=Double.parseDouble(second); double[] array1=new double[month]; double[] array2=new double[month]; double sum1=0,sum2=0; for(int i=0;i<month;i++) { array1[i]=p1/month+(p1-sum1)*firstmonthrate; array2[i]=p2/month+(p2-sum2)*secondmonthrate; Toast.makeText(fangdai.this,array1[i]+" "+array2[i],Toast.LENGTH_LONG); sum1+=array1[i]; sum2+=array2[i]; } String text=""; for(int i=0;i<month;i++){ text+="\n第"+(i+1)+"個月應還金額為:"+String.format("%.2f",(array1[i]+array2[i])*10000)+"元"; } backtotal=sum1+sum2; extra=backtotal-intotal; alldetail.setText("您的貸款總額為"+String.format("%.2f",intotal)+"萬元\n還款總額為"+String.format("%.2f",backtotal)+"萬元\n其中利息總額為"+String.format("%.2f",extra)+"萬元\n還款總時間為"+month+"月\n每月還款金額如下:"+text); } } } } }); row1edit.addTextChangedListener(new TextWatcher() { int oldlength=0; @Override public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) { } @Override public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {//強制用戶不能輸入非數字和小數點之外的字符 int length = charSequence.length(); if (length > oldlength) { char newchar = charSequence.charAt(i); if ((newchar < '0' && newchar > '9') && newchar != '.') { if (i != length - 1) row1edit.setText(charSequence.subSequence(0, i).toString() + charSequence.subSequence(i + 1, length).toString()); else row1edit.setText(charSequence.subSequence(0, length - 1)); } } oldlength=length; } @Override public void afterTextChanged(Editable editable) { } }); row2edit.addTextChangedListener(new TextWatcher() { int oldlength=0; @Override public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) { } @Override public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) { int length=charSequence.length(); if(length>oldlength) { char newchar = charSequence.charAt(i); if ((newchar < '0' && newchar > '9') && newchar != '.') { if (i != length - 1) row2edit.setText(charSequence.subSequence(0, i).toString() + charSequence.subSequence(i + 1, length).toString()); else row2edit.setText(charSequence.subSequence(0, length - 1)); } } oldlength=length; } @Override public void afterTextChanged(Editable editable) { } }); row4edit.addTextChangedListener(new TextWatcher() { int oldlength=0; @Override public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) { } @Override public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) { int length=charSequence.length(); if(length>oldlength) { char newchar = charSequence.charAt(i); if ((newchar < '0' && newchar > '9') && newchar != '.') { if (i != length - 1) row4edit.setText(charSequence.subSequence(0, i).toString() + charSequence.subSequence(i + 1, length).toString()); else row4edit.setText(charSequence.subSequence(0, length - 1)); } } oldlength=length; } @Override public void afterTextChanged(Editable editable) { } }); row5edit.addTextChangedListener(new TextWatcher() { int oldlength=0; @Override public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) { } @Override public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) { int length=charSequence.length(); if(length>oldlength) { char newchar = charSequence.charAt(i); if ((newchar < '0' && newchar > '9') && newchar != '.') { if (i != length - 1) row5edit.setText(charSequence.subSequence(0, i).toString() + charSequence.subSequence(i + 1, length).toString()); else row5edit.setText(charSequence.subSequence(0, length - 1)); } } oldlength=length; } @Override public void afterTextChanged(Editable editable) { } }); } }
fangdaitext(activity)
package com.example.myapplication_one; public class fangdaitext { public static boolean isNum(String string){ int flag=0; if(string.charAt(0)=='0'&&string.charAt(1)!='.') return false; if(string.charAt(0)=='.') return false; for(int i=0;i<string.length();i++) { if((string.charAt(i)<'0'||string.charAt(i)>'9')&&string.charAt(i)!='.') return false; else if(string.charAt(i)=='.') { flag++; if(flag>1) return false; } } return true; } }
fangdai.xml
<?xml version="1.0" encoding="utf-8"?> <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:paddingBottom="@dimen/activity_vertical_margin" android:paddingLeft="@dimen/activity_horizontal_margin" android:paddingRight="@dimen/activity_horizontal_margin" android:paddingTop="16dp" android:focusableInTouchMode="true" android:focusable="true" tools:context="com.example.myapplication_one.fangdai"> <ScrollView android:layout_width="match_parent" android:layout_height="wrap_content"> <RelativeLayout android:layout_width="match_parent" android:layout_height="wrap_content"> <RelativeLayout android:layout_width="match_parent" android:layout_height="wrap_content" android:id="@+id/relativeLayout1"> <TextView android:id="@+id/row1label" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="購房總價:" android:layout_centerVertical="true" android:textSize="18sp" /> <EditText android:id="@+id/row1edit" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_centerVertical="true" android:hint="請輸入購房總價(單位萬)" android:singleLine="true" android:textSize="16dp" android:background="@drawable/edittext_style" android:padding="5dp" android:gravity="right" android:layout_toRightOf="@+id/row1label" android:layout_toLeftOf="@+id/row1endlabel" android:inputType="numberDecimal"/> <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="萬" android:textSize="18sp" android:layout_marginLeft="10dp" android:layout_centerVertical="true" android:layout_alignParentEnd="true" android:id="@+id/row1endlabel" android:layout_alignParentRight="true" /> </RelativeLayout> <RelativeLayout android:layout_width="match_parent" android:layout_height="wrap_content" android:id="@+id/relativeLayout2" android:layout_below="@+id/relativeLayout1" android:layout_marginTop="20dp"> <TextView android:id="@+id/row2label" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="按揭部分:" android:layout_centerVertical="true" android:textSize="18sp" /> <EditText android:id="@+id/row2edit" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_centerVertical="true" android:hint="請輸入按揭百分比" android:singleLine="true" android:textSize="16dp" android:background="@drawable/edittext_style" android:padding="5dp" android:gravity="right" android:layout_toRightOf="@+id/row2label" android:layout_toLeftOf="@+id/row2endlabel" android:inputType="numberDecimal"/> <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:text=" %" android:textSize="18sp" android:layout_marginLeft="10dp" android:layout_centerVertical="true" android:layout_alignParentEnd="true" android:id="@+id/row2endlabel" android:layout_alignParentRight="true" /> </RelativeLayout> <Button android:id="@+id/totalcal" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_below="@+id/relativeLayout2" android:layout_marginTop="15dp" android:background="@drawable/btn_style" android:text="計算貸款總額" /> <TextView android:layout_width="match_parent" android:layout_height="wrap_content" android:text="其中貸款部分為:***萬" android:layout_below="@+id/totalcal" android:layout_marginTop="10dp" android:textSize="16sp" android:id="@+id/showtotal"/> <RelativeLayout android:id="@+id/relativeLayout3" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_below="@+id/showtotal" android:layout_marginTop="10dp"> <TextView android:id="@+id/row3label" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="還款方式:" android:textSize="16sp" android:layout_centerVertical="true"/> <RadioGroup android:id="@+id/radiogroup" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_toRightOf="@+id/row3label" android:orientation="horizontal"> <RadioButton android:id="@+id/btn1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="等額本息" android:checked="true"/> <RadioButton android:id="@+id/btn2" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="等額本金" android:layout_marginLeft="10dp"/> </RadioGroup> </RelativeLayout> <RelativeLayout android:id="@+id/relativeLayout4" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_below="@+id/relativeLayout3"> <CheckBox android:id="@+id/check1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="商貸: "/> <EditText android:id="@+id/row4label" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_centerVertical="true" android:hint="請輸入商業貸款總額(單位萬)" android:singleLine="true" android:textSize="16dp" android:background="@drawable/edittext_style" android:padding="5dp" android:gravity="right" android:layout_toRightOf="@+id/check1" android:layout_toLeftOf="@+id/row4endlabel" android:inputType="numberDecimal"/> <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="萬" android:textSize="18sp" android:layout_marginLeft="10dp" android:layout_centerVertical="true" android:layout_alignParentEnd="true" android:id="@+id/row4endlabel"/> </RelativeLayout> <RelativeLayout android:id="@+id/relativeLayout5" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_below="@+id/relativeLayout4" android:layout_marginTop="5dp"> <CheckBox android:id="@+id/check2" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="公積金:"/> <EditText android:id="@+id/row5label" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_centerVertical="true" android:hint="請輸入公積金貸款總額(單位萬)" android:singleLine="true" android:textSize="16dp" android:background="@drawable/edittext_style" android:padding="5dp" android:gravity="right" android:layout_toRightOf="@+id/check2" android:layout_toLeftOf="@+id/row5endlabel" android:inputType="numberDecimal"/> <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="萬" android:textSize="18sp" android:layout_marginLeft="10dp" android:layout_centerVertical="true" android:layout_alignParentEnd="true" android:id="@+id/row5endlabel" /> </RelativeLayout> <RelativeLayout android:id="@+id/relativeLayout6" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_below="@id/relativeLayout5" android:layout_marginTop="10dp"> <TextView android:id="@+id/row6label" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="貸款年限:" android:textSize="16sp" android:layout_centerVertical="true"/> <Spinner android:id="@+id/sp1" android:layout_centerVertical="true" android:layout_width="match_parent" android:layout_height="wrap_content" android:spinnerMode="dialog" android:layout_toRightOf="@+id/row6label"> </Spinner> </RelativeLayout> <RelativeLayout android:id="@+id/relativeLayout7" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_below="@+id/relativeLayout6" android:layout_marginTop="10dp"> <TextView android:id="@+id/row7label" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="基準利率:" android:layout_centerVertical="true" android:textSize="16sp"/> <Spinner android:id="@+id/sp2" android:layout_width="match_parent" android:layout_height="wrap_content" android:spinnerMode="dialog" android:layout_centerVertical="true" android:layout_toRightOf="@+id/row7label"> </Spinner> </RelativeLayout> <Button android:id="@+id/detail" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_below="@+id/relativeLayout7" android:layout_marginTop="15dp" android:background="@drawable/btn_style" android:text="計算還款明細"/> <TextView android:layout_width="match_parent" android:layout_height="wrap_content" android:text="還款總額為:***萬\n其中利息總額為:***萬\n月供(每月還款額)為:***" android:layout_below="@+id/detail" android:layout_marginTop="10dp" android:textSize="16sp" android:id="@+id/alldetail"/> </RelativeLayout> </ScrollView> </RelativeLayout>
edittext_style.xml
<?xml version="1.0" encoding="utf-8"?> <selector xmlns:android="http://schemas.android.com/apk/res/android"> <item android:state_focused="true"> <shape> <corners android:radius="5dp"/> <stroke android:width="1dp" android:color="#00DDFF"/> </shape> </item> <item android:state_focused="false"> <shape> <corners android:radius="5dp"/> <stroke android:width="1dp" android:color="#000000"/> </shape> </item> </selector>
btn_style.xml
<?xml version="1.0" encoding="utf-8"?> <selector xmlns:android="http://schemas.android.com/apk/res/android"> <item android:state_pressed="true"> <shape> <solid android:color="#808080"/> <corners android:radius="2dp"/> <stroke android:width="1dp" android:color="@color/teal_200"/> </shape> </item> <item android:state_pressed="false"> <shape> <solid android:color="#33E3F3"/> <corners android:radius="2dp"/> <stroke android:width="1dp" android:color="#07AC78"/> </shape> </item> </selector>
dimens.xml
<resources> <!-- Default screen margins, per the Android Design guidelines. --> <dimen name="activity_horizontal_margin">16dp</dimen> <dimen name="activity_vertical_margin">16dp</dimen> </resources>
以上就是本文的全部內容,希望對大傢的學習有所幫助,也希望大傢多多支持WalkonNet。
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