最新最全的Android计算器开发教程
**Android计算器开发**
———————————————————————-我是分割线———————————————————————–
今天分享一款我大一写的计算器，花了三天写出来的，画面比较不错，在计算能力上也相当强大，希望看到这篇文章的你可以学到一些知识。项目源码在我的GitHub里在文章的下面有GitHub的链接点击即可进入下载。
计算器界面效果图：
注释：
哈哈，界面还不错吧，这个界面是我的专业课老师设计的，在这里借鉴了一下0.0。
这个界面的布局是用权重做的分割当然你也可以使用表格来装这个布局，也同样可以实现这个界面效果。当然还有其他方法，可以在下面评论与大家一起分享。
下面就是写这个项目的代码了：
一、主界面逻辑代码MainActivity.java*
package com.calculator.cc;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.Window;
import android.view.WindowManager;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
public class MainActivity extends Activity {
private Button btn3_7;
private EditText edt1_show;
private Button backspace_btn1;
private Button ce_btn2;
private Button btn4_8;
private Button btn5_9;
private Button btn6_chu;
private Button btn7_4;
private Button btn8_5;
private Button btn9_6;
private Button btn10_xing;
private Button btn11_1;
private Button btn12_2;
private Button btn13_3;
private Button btn14_jia;
private Button btn15_0;
private Button btn16_c;
private Button btn17_deng;
private Button btn18_jian;
// 做一个清空的标记
boolean flag;
@Override
protected void onCreate(Bundle savedInstanceState) {
//去掉状态栏
requestWindowFeature(Window.FEATURE_NO_TITLE);
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//使屏幕全屏
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
edt1_show = (EditText) findViewById(R.id.edt1_show);
backspace_btn1 = (Button) findViewById(R.id.backspace_btn1);
ce_btn2 = (Button) findViewById(R.id.ce_btn2);
btn3_7 = (Button) findViewById(R.id.btn3_7);
btn4_8 = (Button) findViewById(R.id.btn4_8);
btn5_9 = (Button) findViewById(R.id.btn5_9);
btn6_chu = (Button) findViewById(R.id.btn6_chu);
btn7_4 = (Button) findViewById(R.id.btn7_4);
btn8_5 = (Button) findViewById(R.id.btn8_5);
btn9_6 = (Button) findViewById(R.id.btn9_6);
btn10_xing = (Button) findViewById(R.id.btn10_xing);
btn11_1 = (Button) findViewById(R.id.btn11_1);
btn12_2 = (Button) findViewById(R.id.btn12_2);
btn13_3 = (Button) findViewById(R.id.btn13_3);
btn14_jia = (Button) findViewById(R.id.btn14_jia);
btn15_0 = (Button) findViewById(R.id.btn15_0);
btn16_c = (Button) findViewById(R.id.btn16_c);
btn17_deng = (Button) findViewById(R.id.btn17_deng);
btn18_jian = (Button) findViewById(R.id.btn18_jian);
// 写单击事件
// 一次删一个
backspace_btn1.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
if (edt1_show.getText().toString() == null
|| (edt1_show.getText().toString()).equals("")) {
return;
} else {
edt1_show.setText((edt1_show.getText().toString()).substring(
0, (edt1_show.getText().toString()).length() - 1));
}
}
});
// 全部清空
ce_btn2.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
edt1_show.setText("");
flag = false;
}
});
btn3_7.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
String seven = edt1_show.getText().toString() + 7;
edt1_show.setText(seven);
}
});
btn4_8.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
String eight = edt1_show.getText().toString() + 8;
edt1_show.setText(eight);
}
});
btn5_9.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
String nine = edt1_show.getText().toString() + 9;
edt1_show.setText(nine);
}
});
btn6_chu.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
if (flag) {
fourOperation();
String chu = edt1_show.getText().toString();
edt1_show.setText(chu.substring(0, chu.length() - 1) + " "
+ "/" + " ");
} else {
String chu = edt1_show.getText().toString() + " " + "/"
+ " ";
edt1_show.setText(chu);
flag = true;
}
}
});
btn7_4.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
String four = edt1_show.getText().toString() + 4;
edt1_show.setText(four);
}
});
btn8_5.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
String five = edt1_show.getText().toString() + 5;
edt1_show.setText(five);
}
});
btn9_6.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
String six = edt1_show.getText().toString() + 6;
edt1_show.setText(six);
}
});
btn10_xing.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
if (flag) {
fourOperation();
String xing = edt1_show.getText().toString();
edt1_show.setText(xing.substring(0, xing.length() - 1)
+ " " + "*" + " ");
} else {
String xing = edt1_show.getText().toString() + " " + "*"
+ " ";
edt1_show.setText(xing);
flag = true;
}
}
});
btn11_1.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
String one = edt1_show.getText().toString() + 1;
edt1_show.setText(one);
}
});
btn12_2.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
String two = edt1_show.getText().toString() + 2;
edt1_show.setText(two);
}
});
btn13_3.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
String three = edt1_show.getText().toString() + 3;
edt1_show.setText(three);
}
});
btn14_jia.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
if (flag) {
fourOperation();
String jia = edt1_show.getText().toString();
edt1_show.setText(jia.substring(0, jia.length() - 1) + " "
+ "+" + " ");
} else {
String jia = edt1_show.getText().toString() + " " + "+"
+ " ";
edt1_show.setText(jia);
flag = true;
}
}
});
btn15_0.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
String zero = edt1_show.getText().toString() + 0;
edt1_show.setText(zero);
}
});
btn16_c.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
String c = edt1_show.getText().toString() + ".";
edt1_show.setText(c);
}
});
btn17_deng.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
getResult();
}
});
btn18_jian.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
if (flag) {
fourOperation();
String jian = edt1_show.getText().toString();
edt1_show.setText(jian.substring(0, jian.length() - 1)
+ " " + "-" + " ");
} else {
String jian = edt1_show.getText().toString() + " " + "-"
+ " ";
edt1_show.setText(jian);
flag = true;
}
}
});
}
// 写等号的方法
private void getResult() {
String deng = edt1_show.getText().toString();
// 判断单击等号时编辑框的内容是否为空
if (deng == null || deng.equals("")) {
return;
}
if (!deng.contains(" ")) {
return;
}
double result = 0;
// 截取加号两边的字符及获得加号
String s1 = deng.substring(0, deng.indexOf(" "));// 运算符前面的字符
String op = deng
.substring(deng.indexOf(" ") + 1, deng.indexOf(" ") + 2);
String s2 = deng.substring(deng.indexOf(" ") + 3);
// s1和s2不为空的情况下进行判断运算
if (!s1.equals("") && !s2.equals("")) {
double d1 = Double.parseDouble(s1);
double d2 = Double.parseDouble(s2);
if (op.equals("+")) {
result = d1 + d2;
} else if (op.equals("-")) {
result = d1 - d2;
} else if (op.equals("*")) {
result = d1 * d2;
} else if (op.equals("/")) {
if (d2 == 0) {
result = 0;
} else {
result = d1 / d2;
}
}
// 判断s1和s2中是否有小数点
if (!s1.contains(".") && !s2.contains(".")) {
int r = (int) result;
if (op.equals("/")) {
edt1_show.setText(result + "");
} else {
edt1_show.setText(r + "");
}
} else {
edt1_show.setText(result + "");
}
// 进行判断是否为一个数时点击等号和为0时的情况
} else if (!s1.equals("") && s2.equals("")) {
edt1_show.setText(edt1_show.getText().toString());
} else if (s1.equals("") && !s2.equals("")) {
double d2 = Double.parseDouble(s2);
if (op.equals("+")) {
result = 0 + d2;
} else if (op.equals("-")) {
result = 0 - d2;
} else if (op.equals("*")) {
result = 0;
} else if (op.equals("/")) {
result = 0;
}
if (!s1.contains(".") && !s2.contains(".")) {
int r = (int) result;
edt1_show.setText(r + "");
} else {
edt1_show.setText(result + "");
}
} else {
edt1_show.setText(" ");
}
}
// 写一个加减乘除的方法
private void fourOperation() {
String deng = edt1_show.getText().toString();
// 判断单击等号时编辑框的内容是否为空
if (deng == null || deng.equals("")) {
return;
}
if (!deng.contains(" ")) {
return;
}
double result = 0;
// 截取加号两边的字符及获得加号
String s1 = deng.substring(0, deng.indexOf(" "));// 运算符前面的字符
String op = deng
.substring(deng.indexOf(" ") + 1, deng.indexOf(" ") + 2);
String s2 = deng.substring(deng.indexOf(" ") + 3);
// s1和s2不为空的情况下进行判断运算
if (!s1.equals("") && !s2.equals("")) {
double d1 = Double.parseDouble(s1);
double d2 = Double.parseDouble(s2);
if (op.equals("+")) {
result = d1 + d2;
} else if (op.equals("-")) {
result = d1 - d2;
} else if (op.equals("*")) {
result = d1 * d2;
} else if (op.equals("/")) {
if (d2 == 0) {
result = 0;
} else {
result = d1 / d2;
}
}
// 判断s1和s2中是否有小数点
if (!s1.contains(".") && !s2.contains(".")) {
int r = (int) result;
if (op.equals("/")) {
edt1_show.setText(result + " ");
} else {
if (op.equals("+")) {
edt1_show.setText(r + " ");
} else if (op.equals("-")) {
edt1_show.setText(r + " ");
} else if (op.equals("*")) {
edt1_show.setText(r + " ");
} else {
edt1_show.setText(r + " ");
}
}
} else {
if (op.equals("+")) {
edt1_show.setText(result + " ");
} else if (op.equals("-")) {
edt1_show.setText(result + " ");
} else if (op.equals("*")) {
edt1_show.setText(result + " ");
} else {
edt1_show.setText(result + " ");
}
}
// 判断式子子右边是否为空
} else if (!s1.equals("") && s2.equals("")) {
if (op.equals("+")) {
edt1_show.setText(result + " ");
} else if (op.equals("-")) {
edt1_show.setText(result + " ");
} else if (op.equals("*")) {
edt1_show.setText(result + " ");
} else {
edt1_show.setText(result + " ");
}
}
}
}
二、面布局代码activity_main.xml
"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:gravity="center"
android:orientation="vertical"
tools:context=".MainActivity" >
"@drawable/click"
android:layout_weight="2"
android:id="@+id/edt1_show"
android:textSize="50sp"
android:layout_width="match_parent"
android:layout_height="0dp"
android:background="#F1D1C6"
/>
"match_parent"
android:layout_height="0dp"
android:orientation="horizontal"
android:layout_weight="2"
>
"match_parent"
android:layout_height="0dp"
android:layout_weight="2"
android:orientation="horizontal" >
"match_parent"
android:layout_height="0dp"
android:layout_weight="2"
android:orientation="horizontal" >
"match_parent"
android:layout_height="0dp"
android:layout_weight="2"
android:orientation="horizontal" >
"match_parent"
android:layout_height="0dp"
android:layout_weight="2"
android:orientation="horizontal" >
这个项目的源码在我的GitHub中点击下面链接即可进入下载:
GitHub:https://github.com/TopGradeModel/Calculator
结语：就先分享这么多，如果对项目有什么不同之处或建议，欢迎大家下面评论出来，大家一起学习和讨论。
版权声明：非商用自由转载-保持署名-注明出处
署名(TM):TopGradeModel