(含完整代码)简易Android计算器的实现
文章结构
-
-
- 1、项目要求
- 2、实现思路
- 3、代码实现
-
-
- 主文件
- 子文件
-
- 4、效果预览
-
1、项目要求
其实老师的要求就是做一个简易的计算器，有两个文本框，一个按钮，然后实现加法即可。
但是我还是想做一个比较好康的计算器（如下），也可以借此写个博客和大家分享一下
2、实现思路
思路就是做一个和平时手机用的计算器差不多的即可。
六行：第一行是显示计算过程和结果的
第二行道第六行是放各种按钮的，直接看效果预览就知道了
By the way，这里我的计算器只是个很粗糙的版本，我已经把UI都搞好了，并且把一些简单的计算都做好了，大家只需要完善一下就可以达到自己的需求了！各位都是学过Java的，相信对大家来说应该不难吧！
代码太多，所以分为
主文件：MainActivity.java、activity_main.xml
子文件：
3、代码实现
主文件
废话不多说，直接上代码
MainActivity.java（这是java文件的代码内容）：
package cn.hillain.myapplication;
import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.TextView;
import android.widget.Toast;
public class MainActivity2 extends AppCompatActivity {
private TextView input;
private TextView result;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
input = this.findViewById(R.id.input);
result = this.findViewById(R.id.result);
}
String input1 = "";
String oper = "";
String input2 = "";
boolean flag = false;
boolean input1_flag = false;
public void oneOnClick(View view){
if(view instanceof TextView){
String oneText = ((TextView)view).getText().toString();
if(flag){
switch (oneText){
case "C":
input.setText("");
result.setText("");
input1 = "";
input2 = "";
oper ="";
input1_flag=false;
flag=false;
break;
}
}else{
switch (oneText){
case "+/-":
break;
case "%":
break;
case "1":
if(!input1_flag){
input1 += "1";
input.setText(input1);
}else{
input2 += "1";
input.setText(input1+oper+input2);
}
break;
case "2":
if(!input1_flag){
input1 += "2";
input.setText(input1);
}else{
input2 += "2";
input.setText(input1+oper+input2);
}
break;
case "3":
if(!input1_flag){
input1 += "3";
input.setText(input1);
}else{
input2 += "3";
input.setText(input1+oper+input2);
}
break;
case "4":
if(!input1_flag){
input1 += "4";
input.setText(input1);
}else{
input2 += "4";
input.setText(input1+oper+input2);
}
break;
case "5":
if(!input1_flag){
input1 += "5";
input.setText(input1);
}else{
input2 += "5";
input.setText(input1+oper+input2);
}
break;
case "6":
if(!input1_flag){
input1 += "6";
input.setText(input1);
}else{
input2 += "6";
input.setText(input1+oper+input2);
}
break;
case "7":
if(!input1_flag){
input1 += "7";
input.setText(input1);
}else{
input2 += "7";
input.setText(input1+oper+input2);
}
break;
case "8":
if(!input1_flag){
input1 += "8";
input.setText(input1);
}else{
input2 += "8";
input.setText(input1+oper+input2);
}
break;
case "9":
if(!input1_flag){
input1 += "9";
input.setText(input1);
}else{
input2 += "9";
input.setText(input1+oper+input2);
}
break;
case "0":
if(!input1_flag){
input1 += "0";
input.setText(input1);
}else{
input2 += "0";
input.setText(input1+oper+input2);
}
break;
case ".":
if(!input1_flag){
input1 += ".";
input.setText(input1);
}else{
input2 += ".";
input.setText(input1+oper+input2);
}
break;
case "÷":
oper = "÷";
input1_flag = true;
input.setText(input1+oper+input2);
break;
case "*":
oper = "*";
input1_flag = true;
input.setText(input1+oper+input2);
break;
case "-":
oper = "-";
input1_flag = true;
input.setText(input1+oper+input2);
break;
case "+":
oper = "+";
input1_flag = true;
input.setText(input1+oper+input2);
break;
case "=":
float num1 = Float.valueOf(input1).floatValue();
float num2 = Float.valueOf(input2).floatValue();
if(oper.equals("+")){
flag = true;
result.setText(String.valueOf(num1+num2));
}
else if(oper.equals("-")){
flag = true;
result.setText(String.valueOf(num1-num2));
}
else if(oper.equals("*")){
flag = true;
result.setText(String.valueOf(num1*num2));
}
if(oper.equals("÷")){
if (num2 == 0) {
Toast.makeText(MainActivity2.this, "除数不能为0", Toast.LENGTH_LONG).show();
}else{
flag = true;
result.setText(String.valueOf(num1/num2));
}
}
break;
}
}
}
}
}
activity_main.xml（layout中的xml文件）：
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<LinearLayout
android:layout_width="match_parent"
android:orientation="horizontal"
android:layout_height="100dp">
<TextView
android:id="@+id/input"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="10dp"
android:layout_marginTop="10dp"
android:text=""
android:textSize="30sp" />
<TextView
android:id="@+id/result"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="195dp"
android:layout_marginTop="50dp"
android:text=""
android:textSize="30sp" />
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:orientation="horizontal"
android:layout_height="80dp">
<TextView
android:id="@+id/C"
android:onClick="oneOnClick"
android:layout_width="0dp"
android:layout_weight="1"
android:layout_height="match_parent"
android:gravity="center"
android:textSize="30sp"
android:background="@drawable/selector_gray1"
android:text="C"/>
<TextView
android:id="@+id/zf"
android:onClick="oneOnClick"
android:layout_width="0dp"
android:layout_weight="1"
android:layout_height="match_parent"
android:gravity="center"
android:textSize="30sp"
android:background="@drawable/selector_gray1"
android:text="+/-"/>
<TextView
android:id="@+id/mo"
android:onClick="oneOnClick"
android:layout_width="0dp"
android:layout_weight="1"
android:layout_height="match_parent"
android:gravity="center"
android:textSize="30sp"
android:background="@drawable/selector_gray1"
android:text="%"/>
<TextView
android:id="@+id/chu"
android:onClick="oneOnClick"
android:layout_width="0dp"
android:layout_weight="1"
android:layout_height="match_parent"
android:gravity="center"
android:textSize="30sp"
android:background="@drawable/selector_gray3"
android:text="÷"/>
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:orientation="horizontal"
android:layout_height="80dp">
<TextView
android:id="@+id/one"
android:onClick="oneOnClick"
android:layout_width="0dp"
android:layout_weight="1"
android:layout_height="match_parent"
android:gravity="center"
android:textSize="30sp"
android:background="@drawable/selector_gray2"
android:text="1"/>
<TextView
android:id="@+id/two"
android:onClick="oneOnClick"
android:layout_width="0dp"
android:layout_weight="1"
android:layout_height="match_parent"
android:gravity="center"
android:textSize="30sp"
android:background="@drawable/selector_gray2"
android:text="2"/>
<TextView
android:id="@+id/three"
android:onClick="oneOnClick"
android:layout_width="0dp"
android:layout_weight="1"
android:layout_height="match_parent"
android:gravity="center"
android:textSize="30sp"
android:background="@drawable/selector_gray2"
android:text="3"/>
<TextView
android:id="@+id/cheng"
android:onClick="oneOnClick"
android:layout_width="0dp"
android:layout_weight="1"
android:layout_height="match_parent"
android:gravity="center"
android:textSize="30sp"
android:background="@drawable/selector_gray3"
android:text="*"/>
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:orientation="horizontal"
android:layout_height="80dp">
<TextView
android:id="@+id/four"
android:onClick="oneOnClick"
android:layout_width="0dp"
android:layout_weight="1"
android:layout_height="match_parent"
android:gravity="center"
android:textSize="30sp"
android:background="@drawable/selector_gray2"
android:text="4"/>
<TextView
android:id="@+id/five"
android:onClick="oneOnClick"
android:layout_width="0dp"
android:layout_weight="1"
android:layout_height="match_parent"
android:gravity="center"
android:textSize="30sp"
android:background="@drawable/selector_gray2"
android:text="5"/>
<TextView
android:id="@+id/six"
android:onClick="oneOnClick"
android:layout_width="0dp"
android:layout_weight="1"
android:layout_height="match_parent"
android:gravity="center"
android:textSize="30sp"
android:background="@drawable/selector_gray2"
android:text="6"/>
<TextView
android:id="@+id/jian"
android:onClick="oneOnClick"
android:layout_width="0dp"
android:layout_weight="1"
android:layout_height="match_parent"
android:gravity="center"
android:textSize="30sp"
android:background="@drawable/selector_gray3"
android:text="-"/>
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:orientation="horizontal"
android:layout_height="80dp">
<TextView
android:id="@+id/seven"
android:onClick="oneOnClick"
android:layout_width="0dp"
android:layout_weight="1"
android:layout_height="match_parent"
android:gravity="center"
android:textSize="30sp"
android:background="@drawable/selector_gray2"
android:text="7"/>
<TextView
android:id="@+id/eight"
android:onClick="oneOnClick"
android:layout_width="0dp"
android:layout_weight="1"
android:layout_height="match_parent"
android:gravity="center"
android:textSize="30sp"
android:background="@drawable/selector_gray2"
android:text="8"/>
<TextView
android:id="@+id/nine"
android:onClick="oneOnClick"
android:layout_width="0dp"
android:layout_weight="1"
android:layout_height="match_parent"
android:gravity="center"
android:textSize="30sp"
android:background="@drawable/selector_gray2"
android:text="9"/>
<TextView
android:id="@+id/jia"
android:onClick="oneOnClick"
android:layout_width="0dp"
android:layout_weight="1"
android:layout_height="match_parent"
android:gravity="center"
android:textSize="30sp"
android:background="@drawable/selector_gray3"
android:text="+"/>
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:orientation="horizontal"
android:layout_height="80dp">
<TextView
android:id="@+id/zero"
android:onClick="oneOnClick"
android:layout_width="0dp"
android:layout_weight="2"
android:layout_height="match_parent"
android:gravity="center_vertical"
android:paddingLeft="44dp"
android:textSize="30sp"
android:background="@drawable/selector_gray2"
android:text="0"/>
<TextView
android:id="@+id/dian"
android:onClick="oneOnClick"
android:layout_width="0dp"
android:layout_weight="1"
android:layout_height="match_parent"
android:gravity="center"
android:textSize="30sp"
android:background="@drawable/selector_gray2"
android:text="."/>
<TextView
android:id="@+id/dengyu"
android:onClick="oneOnClick"
android:layout_width="0dp"
android:layout_weight="1"
android:layout_height="match_parent"
android:gravity="center"
android:textSize="30sp"
android:background="@drawable/selector_gray3"
android:text="="/>
</LinearLayout>
</LinearLayout>
子文件
selector_gray1.xml
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_pressed="true"
android:drawable="@drawable/shape_rectangle_gray1"/>
<item android:drawable="@drawable/shape_rectangle_darkgray"/>
</selector>
selector_gray2.xml
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_pressed="true"
android:drawable="@drawable/shape_rectangle_gray1"/>
<item android:drawable="@drawable/shape_rectangle_lightgray"/>
</selector>
selector_gray3.xml
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_pressed="true"
android:drawable="@drawable/shape_rectangle_gray2"/>
<item android:drawable="@drawable/shape_rectangle_orange"/>
</selector>
shape_rectangle_darkgray.xml
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<solid android:color="#D6D6D6"/>
<stroke android:color="#A1A1A1" android:width="1dp"/>
</shape>
shape_rectangle_gray1.xml
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<solid android:color="#999999"/>
<stroke android:color="#A1A1A1" android:width="1dp"/>
</shape>
shape_rectangle_gray2.xml
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<solid android:color="#b55f1c"/>
<stroke android:color="#A1A1A1" android:width="1dp"/>
</shape>
shape_rectangle_lightgray.xml
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<solid android:color="#E0E0E0"/>
<stroke android:color="#A1A1A1" android:width="1dp"/>
</shape>
shape_rectangle_orange.xml
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<solid android:color="#FF8D27"/>
<stroke android:color="#A1A1A1" android:width="1dp"/>
</shape>
4、效果预览
这么多代码，没有预览，估计大家都不想复制
