android实习程序3

排序（选择 冒泡 插入 快速）

面对对象

static final 

构造方法

继承 （方法重写重载，构造方法不能继承）

抽象 接口 super this 

匿名内部类

collection  

list  （有次序）:  arraylist  vector

set    (没有次序) : Hashset  

Map  :  Hashtable   HashSet  （）

JAVA基本掌握知识

JAVAIO流

多线程 （线程同步 加锁）

Sockect编程 

1、时间的显示（date\Time）

2、改变图片的透明度、与浏览？

3、进度条

4、利用进度条和星级改变图片的透明度

===========================

1、时间的显示

.java

package com.tarena.day03;

import java.util.Calendar;

import android.app.Activity;

import android.os.Bundle;

import android.widget.DatePicker;

import android.widget.DatePicker.OnDateChangedListener;

import android.widget.TimePicker;

import android.widget.Toast;

public class Day03_02Activity extends Activity {

    /** Called when the activity is first created. */

    @Override

    public void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.main);

        

        DatePicker date =(DatePicker) findViewById(R.id.datePicker1);

        TimePicker time = (TimePicker)findViewById(R.id.timePicker1);

        

        Calendar cal = Calendar.getInstance();

        int year = cal.get(Calendar.YEAR);

        int monthOfYear = cal.get(Calendar.MONTH)+2;

        int dayOfMonth = cal.get(Calendar.DAY_OF_MONTH);

        

        date.init(year, monthOfYear, dayOfMonth, new OnDateChangedListener(){

        

@Override

public void onDateChanged(DatePicker view, int year,

int monthOfYear, int dayOfMonth) {

// TODO Auto-generated method stub

Toast.makeText(Day03_02Activity.this, "选择时间是："+year+"年"+monthOfYear+"月"+dayOfMonth+"日", 3000).show();

}

  

        });

time.setOnTimeChangedListener(new OnTimeChangedListener(){

@Override

public void onTimeChanged(TimePicker view, int hourOfDay, int minute) {

// TODO Auto-generated method stub

Toast.makeText(Day03_02Activity.this, "当前时间为："+hourOfDay+"时"+minute+"分", 1000).show();

}        

        });

    }

}

.main

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

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    android:layout_width="fill_parent"

    android:layout_height="fill_parent"

    android:orientation="vertical" 

    android:gravity= "center_horizontal"

    >

    <DatePicker

        android:id="@+id/datePicker1"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content" />

    <TimePicker

        android:id="@+id/timePicker1"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content" />

</LinearLayout>

效果为点击某一时间天，会在下方显示时间

好像有问题，月份不对。。。。。。。

=================================

2、改变图片的透明度、与浏览

.java

package com.tarena.day03;

import android.app.Activity;

import android.graphics.BitmapFactory;

import android.graphics.drawable.BitmapDrawable;

import android.os.Bundle;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.Button;

import android.widget.ImageView;

import android.widget.Toast;

public class Day03_01Activity extends Activity {

   Button plus,minus,next;

   ImageView img;

   int alpha = 255;

   int[] imgs = {R.drawable.a,R.drawable.b,R.drawable.c,R.drawable.d};

   int curInt = 0;

   /** Called when the activity is first created. */

    @Override

    public void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.main_toumingdu);

        

       //初始化组件

        plus = (Button)findViewById(R.id.plus);

        minus = (Button)findViewById(R.id.minus);

        next = (Button)findViewById(R.id.next);

        img = (ImageView)findViewById(R.id.img);

        

        //按next钮添加事件监听

        next.setOnClickListener(new OnClickListener(){

public void onClick(View v) {

curInt++;

if(curInt>=imgs.length){

curInt = imgs.length-1;

Toast.makeText(Day03_01Activity.this, "已经是最后一张图片了", 3000).show();

}

BitmapDrawable dra = (BitmapDrawable)img.getDrawable();

//判断是否回收了之前的图片

if(!dra.getBitmap().isRecycled()){

//把图片回收

dra.getBitmap().recycle();

}

//设置新的图片

img.setImageBitmap(BitmapFactory.decodeResource(getResources(), imgs[curInt]));

}

        });

        plus.setOnClickListener(new MyClick());

        minus.setOnClickListener(new MyClick());

    }

    class MyClick implements OnClickListener{

public void onClick(View v) {

if(v==plus){

alpha+=20;

}else if(v==minus){

alpha-=20;

}

if(alpha<=0){

alpha=0;

}

if(alpha>=255){

alpha=255;

}

// /设置图片的透明度

img.setAlpha(alpha);

}

    

    }

}

main.xml

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

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    android:layout_width="fill_parent"

    android:layout_height="fill_parent"

    android:orientation="vertical" >

    <LinearLayout

        android:layout_width="fill_parent"

        android:layout_height="wrap_content"

        android:gravity="center_horizontal"

        android:orientation="horizontal" >

        <Button

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:text="增大透明度" 

            android:id="@+id/plus"

            />

        <Button

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:text="缩小透明度" 

            android:id="@+id/minus"

            />

        <Button

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:text="下一张" 

            android:id="@+id/next"

            />

    </LinearLayout>

    <ImageView

        android:layout_width="fill_parent"

        android:layout_height="400px"

        android:scaleType="fitCenter"

        android:src="@drawable/a" 

        android:id="@+id/img"

        />

</LinearLayout>

=================================

3、进度条

.java

package com.tarena.day03;

import android.app.Activity;

import android.os.Bundle;

import android.os.Handler;

import android.os.Message;

import android.widget.ProgressBar;

public class processbar extends Activity {

int status=0;

@Override

protected void onCreate(Bundle savedInstanceState) {

// TODO Auto-generated method stub

super.onCreate(savedInstanceState);

setContentView(R.layout.main_jindutiao);

final ProgressBar bar=(ProgressBar)findViewById(R.id.bar);

final Handler h=new Handler(){

@Override

public void handleMessage(Message msg) {

if(msg.what==0x1122){

bar.setProgress(status);

}

}

};

new Thread(){

public void run(){

while(status<=100){

status++;

try {

Thread.sleep(100);

} catch (InterruptedException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

Message msg=new Message();

msg.what=0x1122;

h.sendMessage(msg);

}

}

}.start();

}

}

.main

<?xml version="1.0" encoding="UTF-8"?>

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"

  android:layout_width="fill_parent"

    android:layout_height="fill_parent"

    android:orientation="vertical" >

    

    <ProgressBar

    android:layout_width="fill_parent"

    android:layout_height="wrap_content"

    android:id="@+id/bar"

    style="@android:style/Widget.ProgressBar.Horizontal"

    android:max="100"    

    />       

   

</RelativeLayout>

效果为进度的增加

==================================

4、利用进度条和星级改变图片的透明度

.java

package com.tarena.day03;

import android.app.Activity;

import android.os.Bundle;

import android.view.View;

import android.widget.ImageView;

import android.widget.RatingBar;

import android.widget.RatingBar.OnRatingBarChangeListener;

import android.widget.SeekBar;

import android.widget.SeekBar.OnSeekBarChangeListener;

public class SeekBarActivity extends Activity{

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

   setContentView(R.layout.main);

   

SeekBar bar = (SeekBar)findViewById(R.id.seekBar1);

    final ImageView img = (ImageView)findViewById(R.id.img);

    RatingBar rbar = (RatingBar)findViewById(R.id.ratingBar1);

    

    //对bar添加事件监听

    bar.setOnSeekBarChangeListener(new OnSeekBarChangeListener() {

public void onStopTrackingTouch(SeekBar seekBar) {

}

public void onStartTrackingTouch(SeekBar seekBar) {

}

public void onProgressChanged(SeekBar seekBar, int progress,

boolean fromUser) {

//根据进度条设置透明度

img.setAlpha(progress);

}

});

    //对ratingbar添加事件监听

    rbar.setOnRatingBarChangeListener(new OnRatingBarChangeListener(){

public void onRatingChanged(RatingBar ratingBar, float rating,

boolean fromUser) {

//根据进度条设置透明度

img.setAlpha((int)(255/5*rating));

}

    

    });         

}

}

main.xml

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

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    android:layout_width="fill_parent"

    android:layout_height="fill_parent"

    android:orientation="vertical" 

    android:gravity="center_horizontal"

    >

   <ImageView 

       android:layout_width="fill_parent"

       android:layout_height="400dip"

       android:src="@drawable/a"

       android:scaleType="fitCenter"

       android:id="@+id/img"

       />

    <SeekBar

        android:id="@+id/seekBar1"

        android:layout_width="match_parent"

        android:layout_height="wrap_content" 

        android:max="255"

        android:progress="50"

        />

    <RatingBar

        android:id="@+id/ratingBar1"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:numStars="5"

        android:stepSize="0.5"

        android:max="255"

        android:progress="50"

         />

    </LinearLayout>

实现的效果为：