【移動(dòng)應(yīng)用開(kāi)發(fā)技術(shù)】怎么在Android中實(shí)現(xiàn)一個(gè)首頁(yè)無(wú)限輪播功能

【移動(dòng)應(yīng)用開(kāi)發(fā)技術(shù)】怎么在Android中實(shí)現(xiàn)一個(gè)首頁(yè)無(wú)限輪播功能

這期內(nèi)容當(dāng)中在下將會(huì)給大家?guī)?lái)有關(guān)怎么在Android中實(shí)現(xiàn)一個(gè)首頁(yè)無(wú)限輪播功能，文章內(nèi)容豐富且以專業(yè)的角度為大家分析和敘述，閱讀完這篇文章希望大家可以有所收獲。多張輪播圖定時(shí)效果指示點(diǎn)以及每張圖片的文字說(shuō)明實(shí)現(xiàn)無(wú)限輪播，可滑動(dòng)，圖片點(diǎn)擊事件開(kāi)始布局：<RelativeLayout

xmlns:android="/apk/res/android"

xmlns:tools="/tools"

android:layout_width="match_parent"

android:layout_height="match_parent"

tools:context="com.yangziling.carousel.MainActivity">

<!--輪播圖-->

<FrameLayout

android:layout_width="match_parent"

android:layout_height="200dp">

<android.support.v4.view.ViewPager

android:id="@+id/vp"

android:layout_width="match_parent"

android:layout_height="match_parent"/>

<!--指示點(diǎn)和圖片標(biāo)題-->

<LinearLayout

android:layout_width="match_parent"

android:layout_height="35dip"

android:layout_gravity="bottom"

android:background="#33000000"

android:gravity="center"

android:orientation="vertical">

<!--圖片配文-->

<TextView

android:id="@+id/title"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:text="圖片標(biāo)題"

android:textColor="@android:color/white"

/>

<LinearLayout

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_marginTop="3dip"

android:orientation="horizontal"

>

<!--指示點(diǎn)-->

<View

android:id="@+id/dot_0"

android:background="@drawable/dot_focused"/>

<View

android:id="@+id/dot_1"

android:background="@drawable/dot_normal"/>

<View

android:id="@+id/dot_2"

android:background="@drawable/dot_normal"/>

<View

android:id="@+id/dot_3"

android:background="@drawable/dot_normal"/>

<View

android:id="@+id/dot_4"

android:background="@drawable/dot_normal"/>

</LinearLayout>

</LinearLayout>

</FrameLayout>

</RelativeLayout>布局中抽取的view屬性：<style

name="view_attr">

<item

name="android:layout_width">5dp</item>

<item

name="android:layout_height">5dp</item>

<item

name="android:layout_marginLeft">5dp</item>

<item

name="android:layout_marginRight">5dp</item>

</style>這里我展示的一些圖片是在本地的，通過(guò)網(wǎng)絡(luò)框架加載圖片原理也是一樣的。這里直接給大家貼出來(lái)核心代碼：public

class

MainActivity

extends

AppCompatActivity

{

private

ViewPager

mMyViewPaper;

private

List<ImageView>

images;

private

List<View>

dots;

private

int

currentItem;

private

TextView

title;

private

MyAdapter

adapter;

//當(dāng)前顯示圖片的位置

private

int

localPosition

=

0;

//圖片的id

private

int[]

imageIds

=

new

int[]{R.drawable.a,

R.drawable.b,

R.drawable.c,

R.drawable.d,

R.drawable.e};

//圖片的標(biāo)題

private

String[]

titles

=

new

String[]{"藍(lán)天白云",

"青山綠水",

"枯藤老樹(shù)",

"人間仙境",

"島嶼大樹(shù)"};

private

TimerTask

mTimerTask;

//創(chuàng)建一個(gè)定時(shí)器

private

final

Timer

timer

=

new

Timer();

private

ImageView

mImageView;

@Override

protected

void

onCreate(Bundle

savedInstanceState)

{

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

mMyViewPaper

=

(ViewPager)

findViewById(R.id.vp);

//顯示的圖片

images

=

new

ArrayList<>();

for

(int

i

=

0;

i

<

imageIds.length;

i++)

{

mImageView

=

new

ImageView(this);

mImageView.setBackgroundResource(imageIds[i]);

images.add(mImageView);

}

//指示點(diǎn)

dots

=

new

ArrayList<>();

dots.add(findViewById(R.id.dot_0));

dots.add(findViewById(R.id.dot_1));

dots.add(findViewById(R.id.dot_2));

dots.add(findViewById(R.id.dot_3));

dots.add(findViewById(R.id.dot_4));

title

=

(TextView)

findViewById(R.id.title);

title.setText(titles[0]);

adapter

=

new

MyAdapter(MainActivity.this,

images);

mMyViewPaper.setAdapter(adapter);

mMyViewPaper.setOnPageChangeListener(new

ViewPager.OnPageChangeListener()

{

@Override

public

void

onPageSelected(int

position)

{

position

=

position

%

images.size();

title.setText(titles[position]);

dots.get(position).setBackgroundResource(R.drawable.dot_focused);

dots.get(localPosition).setBackgroundResource(R.drawable.dot_normal);

localPosition

=

position;

currentItem

=

position;

}

/**

*

頁(yè)面滑動(dòng)時(shí)回調(diào)

*/

@Override

public

void

onPageScrolled(int

arg0,

float

arg1,

int

arg2)

{

}

/**

*

當(dāng)ViewPager狀態(tài)改變時(shí)，回調(diào)

*/

@Override

public

void

onPageScrollStateChanged(int

state)

{

}

});

}

/**

*

輪播任務(wù)

*/

@Override

protected

void

onStart()

{

super.onStart();

mTimerTask

=

new

TimerTask()

{

@Override

public

void

run()

{

currentItem

=

(currentItem

+

1)

%

imageIds.length;

mHandler.sendEmptyMessage(0);

}

};

timer.schedule(mTimerTask,

2000,

2000);

}

/**

*

接收子線程傳遞的數(shù)據(jù)

*/

private

Handler

mHandler

=

new

Handler()

{

public

void

handleMessage(android.os.Message

msg)

{

//輪播到最后一張圖片時(shí)，直接跳轉(zhuǎn)至第一頁(yè)，并且取消滑動(dòng)效果

if

(currentItem

%

images.size()

==

0)

{

mMyViewPaper.setCurrentItem(currentItem,

false);

}

//非最后一張展示圖片的滑動(dòng)效果

mMyViewPaper.setCurrentItem(currentItem,

true);

}

};

@Override

protected

void

onStop()

{

super.onStop();

timer.cancel();

}

}自定義了一個(gè)Adapter適配器：public

class

MyAdapter

extends

PagerAdapter

{

private

List<ImageView>

images;

private

Context

mContext;

public

MyAdapter(Context

context,List<ImageView>

images)

{

this.mContext

=context;

this.images

=

images;

}

//返回Viewpager中的view個(gè)數(shù)

@Override

public

int

getCount()

{

return

Integer.MAX_VALUE;

}

//判斷instantiateItem中的函數(shù)返回的key與一個(gè)頁(yè)面示圖是不是代表同一個(gè)

//通常直接相等就OK啦

@Override

public

boolean

isViewFromObject(View

arg0,

Object

arg1)

{

return

arg0

==

arg1;

}

//移除一個(gè)固定位置的頁(yè)面

@Override

public

void

destroyItem(ViewGroup

view,

int

position,

Object

object)

{

view.removeView((View)

object);

}

//將固定位置的View添加到Viewgroup中，并創(chuàng)建顯示出來(lái)

@Override

public

Object

instantiateItem(ViewGroup

view,

final

int

position)

{

ImageView

imageView

=

images.get(position

%

images.size());

ViewGroup

parent

=

(ViewGroup)

imageView.getParent();

//這里是動(dòng)態(tài)添加示圖，一個(gè)子類只能有一個(gè)父類

//判斷下如果parent存在一定要記得移除

if

(parent

!=

null)

{

parent.removeView(imageView);

}

view.addView(imageView);

//給圖片添加點(diǎn)擊事件

imageView.setOnClickListener(new

View.OnClickListener(){

@Override

public

void

onClick(View

v