android打造的最简单计算器界面
先看图：
这里主要是锻炼一下TableLayout布局，注意其中的android:stretchColumns="0,1,2,3"属性，该属性可以控制每列的宽的权重，类似weight，由于这里4列都是“平等的”，所以是“0，1，2，3”，全部布局文件如下：
<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent" > <EditText android:id="@+id/result" android:layout_width="fill_parent" android:layout_height="wrap_content"android:text=""android:singleLine="true"android:numeric="decimal"android:focusable="false"android:digits="1234567890."android:cursorVisible="false"/><TableLayout android:layout_width="fill_parent" android:layout_height="wrap_content"android:stretchColumns="0,1,2,3"><TableRow><Button android:id="@+id/btn_1" android:text="1"/><Button android:id="@+id/btn_2" android:text="2" /><Button android:id="@+id/btn_3" android:text="3" /><Button android:id="@+id/btn_add" android:text="+" /></TableRow><TableRow><Button android:id="@+id/btn_4" android:text="4" /><Button android:id="@+id/btn_5" android:text="5" /><Button android:id="@+id/btn_6" android:text="6" /><Button android:id="@+id/btn_sub" android:text="-" /></TableRow><TableRow><Button android:id="@+id/btn_7" android:text="7" /><Button android:id="@+id/btn_8" android:text="8" /><Button android:id="@+id/btn_9" android:text="9" /><Button android:id="@+id/btn_mul" android:text="*" /></TableRow><TableRow><Button android:id="@+id/btn_dot" android:text="." /><Button android:id="@+id/btn_0" android:text="0" /><Button android:id="@+id/btn_eq" android:text="=" /><Button android:id="@+id/btn_div" android:text="/" /></TableRow></TableLayout><Button android:id="@+id/btn_clear" android:layout_width="fill_parent" android:layout_height="wrap_content"android:text="clear"/></LinearLayout>
package com.wt.app;import android.app.Activity;import android.os.Bundle;import android.view.View;import android.widget.Button;import android.widget.EditText;public class App extends Activity {EditText editText;StringBuffer text;String number_1="",number_2="";boolean clicked=false;byte style=0;Button btn_1,btn_2,btn_3,btn_4,btn_5,btn_6,btn_7,btn_8,btn_9,btn_0;Button btn_add,btn_sub,btn_mul,btn_div,btn_eq,btn_dot,btn_clear; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); text=new StringBuffer(); editText=(EditText)findViewById(R.id.result); //editText.setFocusable(false); btn_1=(Button) findViewById(R.id.btn_1); btn_1.setOnClickListener(new Button.OnClickListener(){public void onClick(View v) {// TODO Auto-generated method stubif(clicked){editText.setText("");clicked=false;text.setLength(0);}text.append("1");editText.setText(text.toString());} }); btn_2=(Button) findViewById(R.id.btn_2); btn_2.setOnClickListener(new Button.OnClickListener(){ public void onClick(View v) { // TODO Auto-generated method stub if(clicked){editText.setText("");clicked=false;text.setLength(0);} text.append("2"); editText.setText(text.toString()); } }); btn_3=(Button) findViewById(R.id.btn_3); btn_3.setOnClickListener(new Button.OnClickListener(){ public void onClick(View v) { // TODO Auto-generated method stub if(clicked){editText.setText("");clicked=false;text.setLength(0);} text.append("3"); editText.setText(text.toString()); } }); btn_4=(Button) findViewById(R.id.btn_4); btn_4.setOnClickListener(new Button.OnClickListener(){ public void onClick(View v) { // TODO Auto-generated method stub if(clicked){editText.setText("");clicked=false;text.setLength(0);} text.append("4"); editText.setText(text.toString()); } }); btn_5=(Button) findViewById(R.id.btn_5); btn_5.setOnClickListener(new Button.OnClickListener(){ public void onClick(View v) { // TODO Auto-generated method stub if(clicked){editText.setText("");clicked=false;text.setLength(0);} text.append("5"); editText.setText(text.toString()); } }); btn_6=(Button) findViewById(R.id.btn_6); btn_6.setOnClickListener(new Button.OnClickListener(){ public void onClick(View v) { // TODO Auto-generated method stub if(clicked){editText.setText("");clicked=false;text.setLength(0);} text.append("6"); editText.setText(text.toString()); } }); btn_7=(Button) findViewById(R.id.btn_7); btn_7.setOnClickListener(new Button.OnClickListener(){ public void onClick(View v) { // TODO Auto-generated method stub if(clicked){editText.setText("");clicked=false;text.setLength(0);} text.append("7"); editText.setText(text.toString()); } }); btn_8=(Button) findViewById(R.id.btn_8); btn_8.setOnClickListener(new Button.OnClickListener(){ public void onClick(View v) { // TODO Auto-generated method stub if(clicked){editText.setText("");clicked=false;text.setLength(0);} text.append("8"); editText.setText(text.toString()); } }); btn_9=(Button) findViewById(R.id.btn_9); btn_9.setOnClickListener(new Button.OnClickListener(){ public void onClick(View v) { // TODO Auto-generated method stub if(clicked){editText.setText("");clicked=false;text.setLength(0);} text.append("9"); editText.setText(text.toString()); } }); btn_0=(Button) findViewById(R.id.btn_0); btn_0.setOnClickListener(new Button.OnClickListener(){ public void onClick(View v) { // TODO Auto-generated method stub if(clicked){editText.setText("");clicked=false;text.setLength(0);} text.append("0"); editText.setText(text.toString()); } }); btn_dot=(Button) findViewById(R.id.btn_dot); btn_dot.setOnClickListener(new Button.OnClickListener(){ public void onClick(View v) { // TODO Auto-generated method stub if(clicked){editText.setText("");clicked=false;text.setLength(0);} if(editText.getText().toString().indexOf(".")==-1){//已经有.了 if(text.length()==0){ text.append("0."); }else{ text.append("."); } editText.setText(text.toString()); } } }); btn_add=(Button) findViewById(R.id.btn_add); btn_add.setOnClickListener(new Button.OnClickListener(){ public void onClick(View v) { // TODO Auto-generated method stub number_1=editText.getText().toString(); style=1; clicked=true; } }); btn_sub=(Button) findViewById(R.id.btn_sub); btn_sub.setOnClickListener(new Button.OnClickListener(){ public void onClick(View v) { // TODO Auto-generated method stub number_1=editText.getText().toString(); style=2; clicked=true; } }); btn_mul=(Button) findViewById(R.id.btn_mul); btn_mul.setOnClickListener(new Button.OnClickListener(){ public void onClick(View v) { // TODO Auto-generated method stub number_1=editText.getText().toString(); style=3; clicked=true; } }); btn_div=(Button) findViewById(R.id.btn_div); btn_div.setOnClickListener(new Button.OnClickListener(){ public void onClick(View v) { // TODO Auto-generated method stub number_1=editText.getText().toString(); style=4; clicked=true; } }); btn_eq=(Button) findViewById(R.id.btn_eq); btn_eq.setOnClickListener(new Button.OnClickListener(){ public void onClick(View v) { // TODO Auto-generated method stub number_2=editText.getText().toString(); if(number_1.equals("")&&number_2.equals("")){ return; } Double d1=Double.valueOf(number_1); Double d2=Double.valueOf(number_2); Double r=0.0;; switch (style) {case 1:r=d1+d2;break;case 2:r=d1-d2;break;case 3:r=d1*d2;break;case 4:r=d1/d2;break;} editText.setText(r.toString()); } }); btn_clear=(Button) findViewById(R.id.btn_clear); btn_clear.setOnClickListener(new Button.OnClickListener(){ public void onClick(View v) { // TODO Auto-generated method stub editText.setText(""); number_1=""; number_2=""; style=0; clicked=false; text.setLength(0); } }); } }