Android初学之路（一）

之前要做单片机小项目——无线点阵广告牌！涉及到编写一个简单安卓软件......所以只有一点儿基础的我开始学习安卓了！第一天，当然学习一些简单了！主要是几个控件和监听的写法,还有Activity的生命周期等等！还有对XML的一些理解！本篇日志纯属个人足迹记录！不多说！今天写的代码贴上了！

首先是我写的第一个Activity，代码如下：

package com.example.helloandroid;

import android.net.Uri;
import android.os.Bundle;
import android.app.Activity;
import android.app.SearchManager.OnCancelListener;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.DialogInterface.OnClickListener;
import android.support.v4.widget.SimpleCursorAdapter.ViewBinder;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.SearchView.OnCloseListener;
import android.widget.TextView;

public class MainActivity extends Activity {

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);

Button my_button01 = (Button) findViewById(R.id.Button01);
Button my_button02 = (Button) findViewById(R.id.Button02);
Button my_button03 = (Button) findViewById(R.id.Button03);
Button my_button04 = (Button) findViewById(R.id.Button04);
TextView my_textview01 = (TextView) findViewById(R.id.TestView01);

my_button01.setText(R.string.f_button);
my_button02.setText(R.string.msg);
my_button03.setText(R.string.cheng);
my_button04.setText(R.string.dig);
my_textview01.setText("hello");

my_button01.setOnClickListener(new Button_linstener());
/*
* 隐式实现监听，写法抽象，但是写代码快。
*/
my_button02.setOnClickListener(new Button.OnClickListener() {

@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
Uri uri = Uri.parse("smsto://0800000123");
Intent intent = new Intent(Intent.ACTION_SENDTO,uri);
intent.putExtra("sms_body", "你好");
startActivity(intent);
}
});

my_button03.setOnClickListener(new Button.OnClickListener() {

@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
Intent intent = new Intent();
intent.setClass(MainActivity.this, OthersActivty02.class);
startActivity(intent);
}
});

my_button04.setOnClickListener(new Button.OnClickListener() {

@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
Intent intent = new Intent();
intent.setClass(MainActivity.this, OthersActivty04.class);
startActivity(intent);
}
});
System.out.println("main on create");
}

@Override
protected void onStart() {
// TODO Auto-generated method stub
super.onStart();
System.out.println("main on start");
}

protected void onRestart() {
// TODO Auto-generated method stub
super.onRestart();
System.out.println("main on restart");
}

@Override
protected void onResume() {
// TODO Auto-generated method stub
super.onResume();
System.out.println("main on resume");
}

@Override
protected void onPause() {
// TODO Auto-generated method stub
super.onPause();
System.out.println("main on pause");
}

@Override
protected void onStop() {
// TODO Auto-generated method stub
super.onStop();
System.out.println("main on stop");
}

@Override
protected void onDestroy() {
// TODO Auto-generated method stub
super.onDestroy();
System.out.println("main on destory");
}

/*
* 内部类实现监听
*/
class Button_linstener implements View.OnClickListener{

@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
Intent intent = new Intent();
intent.putExtra("testintent", "123");
intent.setClass(MainActivity.this, OthersActivity01.class);
MainActivity.this.startActivity(intent);
}

}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
menu.add(0,1,1,R.string.exit);
menu.add(0,2,2,R.string.about);

//getMenuInflater().inflate(R.menu.main, menu);
return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
// TODO Auto-generated method stub
if(item.getItemId() == 1){
finish();
}
return super.onOptionsItemSelected(item);
}

}
XML布局
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >

<TextView
android:id="@+id/TestView01"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/app_name"/>

<Button
android:id="@+id/Button01"
android:layout_width="fill_parent"
android:layout_height="wrap_content"/>
<Button
android:id="@+id/Button02"
android:layout_width="fill_parent"
android:layout_height="wrap_content"/>
<Button
android:id="@+id/Button03"
android:layout_width="fill_parent"
android:layout_height="wrap_content"/>
<Button
android:id="@+id/Button04"
android:layout_width="fill_parent"
android:layout_height="wrap_content"/>

</LinearLayout>

之后的三个Activity
package com.example.helloandroid;

import com.example.helloandroid.MainActivity.Button_linstener;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

public class OthersActivty02 extends Activity{
private EditText edit01 = null;
private EditText edit02 = null;
private TextView text01 = null;
private Button button01 = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_other02);

edit01 = (EditText) findViewById(R.id.edit01);
edit02 = (EditText) findViewById(R.id.edit02);
text01 = (TextView) findViewById(R.id.text02);
button01 = (Button) findViewById(R.id.button02);

text01.setText(R.string.alu);
button01.setText(R.string.result);

button01.setOnClickListener(new Button.OnClickListener() {

@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
String f_edit = edit01.getText().toString();
String s_edit = edit02.getText().toString();

Intent intent = new Intent();
intent.putExtra("one", f_edit);
intent.putExtra("two",s_edit);

intent.setClass(OthersActivty02.this,OthersActivity03.class);
startActivity(intent);
}
});

}
}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<EditText
android:id="@+id/edit01"
android:layout_width="fill_parent"
android:layout_height="wrap_content"/>
<TextView
android:id="@+id/text02"
android:layout_width="fill_parent"
android:layout_height="wrap_content"/>
<EditText
android:id="@+id/edit02"
android:layout_width="fill_parent"
android:layout_height="wrap_content"/>
<Button
android:id="@+id/button02"
android:layout_width="fill_parent"
android:layout_height="wrap_content"/>

</LinearLayout>

package com.example.helloandroid;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.widget.TextView;

public class OthersActivity01 extends Activity{

private TextView my_textview02 = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_other01);

Intent intent = getIntent();
String value = intent.getStringExtra("testintent");

my_textview02 = (TextView) findViewById(R.id.TextView02);
my_textview02.setText(value);

System.out.println("01 on create");
}

@Override
protected void onStart() {
// TODO Auto-generated method stub
super.onStart();
System.out.println("01 on start");
}

@Override
protected void onRestart() {
// TODO Auto-generated method stub
super.onRestart();
System.out.println("01 on restart");
}

@Override
protected void onResume() {
// TODO Auto-generated method stub
super.onResume();
System.out.println("01 on resume");
}

@Override
protected void onPause() {
// TODO Auto-generated method stub
super.onPause();
System.out.println("01 on pause");
}

@Override
protected void onStop() {
// TODO Auto-generated method stub
super.onStop();
System.out.println("01 on stop");
}

@Override
protected void onDestroy() {
// TODO Auto-generated method stub
super.onDestroy();
System.out.println("01 on destory");
}
}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<TextView
android:id="@+id/TextView02"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/app_name"/>

</LinearLayout>

package com.example.helloandroid;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.widget.TextView;

public class OthersActivity03 extends Activity{
private TextView mytext = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_other03);

mytext = (TextView) findViewById(R.id.result_test);

Intent intent = getIntent();
String f_str = intent.getStringExtra("one");
String s_str = intent.getStringExtra("two");

int f_int = Integer.parseInt(f_str);
int s_int = Integer.parseInt(s_str);

int results = f_int * s_int;

mytext.setText(results + "");

}
}

package com.example.helloandroid;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;

public class OthersActivty04 extends Activity{
private Button back_button = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_other04);

back_button = (Button) findViewById(R.id.dig_button);
back_button.setText(R.string.dig_back);

back_button.setOnClickListener(new OnClickListener() {

@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
finish();
}
});
System.out.println("04 on create");
}

@Override
protected void onStart() {
// TODO Auto-generated method stub
super.onStart();
System.out.println("04 on start");
}

@Override
protected void onRestart() {
// TODO Auto-generated method stub
super.onRestart();
System.out.println("04 on restart");
}

@Override
protected void onResume() {
// TODO Auto-generated method stub
super.onResume();
System.out.println("04 on resume");
}

@Override
protected void onPause() {
// TODO Auto-generated method stub
super.onPause();
System.out.println("04 on pause");
}

@Override
protected void onStop() {
// TODO Auto-generated method stub
super.onStop();
System.out.println("04 on stop");
}

@Override
protected void onDestroy() {
// TODO Auto-generated method stub
super.onDestroy();
System.out.println("04 on destory");
}
}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<TextView
android:id="@+id/result_test"
android:layout_width="fill_parent"
android:layout_height="wrap_content"/>

</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<TextView
android:id="@+id/dig_text"
android:layout_width="fill_parent"
android:layout_height="wrap_content"/>
<Button
android:id="@+id/dig_button"
android:layout_width="fill_parent"
android:layout_height="wrap_content"/>

</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<resources>

<string name="app_name">HelloAndroid</string>
<string name="action_settings">Settings</string>
<string name="hello_world">Hello world!</string>
<string name="exit">退出</string>
<string name="about">关于</string>
<string name="alu">乘以</string>
<string name="result">等于</string>
<string name="cheng">乘法器</string>
<string name="f_button">我的第一个按钮</string>
<string name="msg">短信</string>
<string name="dig_back">返回第一个Activity</string>
<string name="dig">小窗口Activity</string>

</resources>