一、首先,我们来看一下效果图,这是新浪微博的Tab滑动效果。我们可以手势滑动,也可以点击上面的头标进行切换。与此同方式,
白色横条会移动到相应的页卡头标下。这是一个动画效果,白条是缓慢滑动过去的。好了,接下来我们就来实现它。
二、在开始前,我们先要认识一个控件,ViewPager。它是是google SDk中自带的一个附加包的一个类,可以用来实现屏幕间的切换。
这个附加包是android-support-v4.jar,在最后的源码中会提供给大家,在libs文件夹中。当然你也可以自己从网上搜索最新的版本。
找到它后,我们需要在项目中添加
三、我们先做界面,
界面设计很简单,第一行三个头标,第二行动画图片,第三行页卡内容展示。
01 |
<? xml version = "1.0" encoding = "utf-8" ?> |
02 |
< LinearLayout xmlns:android = "http://schemas.android.com/apk/res/android" |
03 |
xmlns:umadsdk = "http://schemas.android.com/apk/res/com.LoveBus" |
04 |
android:layout_width = "fill_parent" |
05 |
android:layout_height = "fill_parent" |
06 |
android:orientation = "vertical" > |
07 |
08 |
< LinearLayout |
09 |
android:id = "@+id/linearLayout1" |
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android:layout_width = "fill_parent" |
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android:layout_height = "100.0dip" |
12 |
android:background = "#FFFFFF" > |
13 |
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< TextView |
15 |
android:id = "@+id/text1" |
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android:layout_width = "fill_parent" |
17 |
android:layout_height = "fill_parent" |
18 |
android:layout_weight = "1.0" |
19 |
android:gravity = "center" |
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android:text = "页卡1" |
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android:textColor = "#000000" |
22 |
android:textSize = "22.0dip" /> |
23 |
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< TextView |
25 |
android:id = "@+id/text2" |
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android:layout_width = "fill_parent" |
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android:layout_height = "fill_parent" |
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android:layout_weight = "1.0" |
29 |
android:gravity = "center" |
30 |
android:text = "页卡2" |
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android:textColor = "#000000" |
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android:textSize = "22.0dip" /> |
33 |
34 |
< TextView |
35 |
android:id = "@+id/text3" |
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android:layout_width = "fill_parent" |
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android:layout_height = "fill_parent" |
38 |
android:layout_weight = "1.0" |
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android:gravity = "center" |
40 |
android:text = "页卡3" |
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android:textColor = "#000000" |
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android:textSize = "22.0dip" /> |
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</ LinearLayout > |
44 |
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< ImageView |
46 |
android:id = "@+id/cursor" |
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android:layout_width = "fill_parent" |
48 |
android:layout_height = "wrap_content" |
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android:scaleType = "matrix" |
50 |
android:src = "@drawable/a" /> |
51 |
52 |
< android.support.v4.view.ViewPager |
53 |
android:id = "@+id/vPager" |
54 |
android:layout_width = "wrap_content" |
55 |
android:layout_height = "wrap_content" |
56 |
android:layout_gravity = "center" |
57 |
android:layout_weight = "1.0" |
58 |
android:background = "#000000" |
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android:flipInterval = "30" |
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android:persistentDrawingCache = "animation" /> |
61 |
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</ LinearLayout > |
我们要展示三个页卡,所以还需要三个页卡内容的界面设计,这里我们只设置了背景颜色,能起到区别作用即可。
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<? xml version = "1.0" encoding = "utf-8" ?> |
2 |
< LinearLayout xmlns:android = "http://schemas.android.com/apk/res/android" |
3 |
android:layout_width = "fill_parent" |
4 |
android:layout_height = "fill_parent" |
5 |
android:orientation = "vertical" |
6 |
android:background = "#158684" > |
7 |
</ LinearLayout > |
四、代码部分要进行初始化的工作
(1) 先来变量的定义
1 |
private ViewPager
mPager; //页卡内容 |
2 |
private List<View>
listViews; //
Tab页面列表 |
3 |
private ImageView
cursor; //
动画图片 |
4 |
private TextView
t1, t2, t3; //
页卡头标 |
5 |
private int offset
= 0 ; //
动画图片偏移量 |
6 |
private int currIndex
= 0 ; //
当前页卡编号 |
7 |
private int bmpW; //
动画图片宽度 |
01 |
/** |
02 |
*
初始化头标 |
03 |
*/ |
04 |
private void InitTextView()
{ |
05 |
t1
= (TextView) findViewById(R.id.text1); |
06 |
t2
= (TextView) findViewById(R.id.text2); |
07 |
t3
= (TextView) findViewById(R.id.text3); |
08 |
|
09 |
t1.setOnClickListener( new MyOnClickListener( 0 )); |
10 |
t2.setOnClickListener( new MyOnClickListener( 1 )); |
11 |
t3.setOnClickListener( new MyOnClickListener( 2 )); |
12 |
} |
01 |
/** |
02 |
*
头标点击监听 |
03 |
*/ |
04 |
public class MyOnClickListener implements View.OnClickListener
{ |
05 |
private int index
= 0 ; |
06 |
|
07 |
public MyOnClickListener( int i)
{ |
08 |
index
= i; |
09 |
} |
10 |
|
11 |
@Override |
12 |
public void onClick(View
v) { |
13 |
mPager.setCurrentItem(index); |
14 |
} |
15 |
}; |
相信大家看后都没什么问题,点击第几个,就展示第几个页卡内容。
(3) 初始化页卡内容区
01 |
/** |
02 |
*
初始化ViewPager |
03 |
*/ |
04 |
private void InitViewPager()
{ |
05 |
mPager
= (ViewPager) findViewById(R.id.vPager); |
06 |
listViews
= new ArrayList<View>(); |
07 |
LayoutInflater
mInflater = getLayoutInflater(); |
08 |
listViews.add(mInflater.inflate(R.layout.lay1, null )); |
09 |
listViews.add(mInflater.inflate(R.layout.lay2, null )); |
10 |
listViews.add(mInflater.inflate(R.layout.lay3, null )); |
11 |
mPager.setAdapter( new MyPagerAdapter(listViews)); |
12 |
mPager.setCurrentItem( 0 ); |
13 |
mPager.setOnPageChangeListener( new MyOnPageChangeListener()); |
14 |
} |
我们将三个页卡界面装入其中,默认显示第一个页卡。这里我们还需要实现一个适配器。
01 |
/** |
02 |
*
ViewPager适配器 |
03 |
*/ |
04 |
public class MyPagerAdapter extends PagerAdapter
{ |
05 |
public List<View>
mListViews; |
06 |
|
07 |
public MyPagerAdapter(List<View>
mListViews) { |
08 |
this .mListViews
= mListViews; |
09 |
} |
10 |
|
11 |
@Override |
12 |
public void destroyItem(View
arg0, int arg1,
Object arg2) { |
13 |
((ViewPager)
arg0).removeView(mListViews.get(arg1)); |
14 |
} |
15 |
|
16 |
@Override |
17 |
public void finishUpdate(View
arg0) { |
18 |
} |
19 |
|
20 |
@Override |
21 |
public int getCount()
{ |
22 |
return mListViews.size(); |
23 |
} |
24 |
|
25 |
@Override |
26 |
public Object
instantiateItem(View arg0, int arg1)
{ |
27 |
((ViewPager)
arg0).addView(mListViews.get(arg1), 0 ); |
28 |
return mListViews.get(arg1); |
29 |
} |
30 |
|
31 |
@Override |
32 |
public boolean isViewFromObject(View
arg0, Object arg1) { |
33 |
return arg0
== (arg1); |
34 |
} |
35 |
|
36 |
@Override |
37 |
public void restoreState(Parcelable
arg0, ClassLoader arg1) { |
38 |
} |
39 |
|
40 |
@Override |
41 |
public Parcelable
saveState() { |
42 |
return null ; |
43 |
} |
44 |
|
45 |
@Override |
46 |
public void startUpdate(View
arg0) { |
47 |
} |
48 |
} |
这里我们实现了各页卡的装入和卸载
(3) 初始化动画
01 |
/** |
02 |
*
初始化动画 |
03 |
*/ |
04 |
private void InitImageView()
{ |
05 |
cursor
= (ImageView) findViewById(R.id.cursor); |
06 |
bmpW
= BitmapFactory.decodeResource(getResources(), R.drawable.a) |
07 |
.getWidth(); //
获取图片宽度 |
08 |
DisplayMetrics
dm = new DisplayMetrics(); |
09 |
getWindowManager().getDefaultDisplay().getMetrics(dm); |
10 |
int screenW
= dm.widthPixels; //
获取分辨率宽度 |
11 |
offset
= (screenW / 3 -
bmpW) / 2 ; //
计算偏移量 |
12 |
Matrix
matrix = new Matrix(); |
13 |
matrix.postTranslate(offset, 0 ); |
14 |
cursor.setImageMatrix(matrix); //
设置动画初始位置 |
15 |
} |
根据屏幕的分辨率和图片的宽度计算动画移动的偏移量
实现页卡切换监听
01 |
/** |
02 |
*
页卡切换监听 |
03 |
*/ |
04 |
public class MyOnPageChangeListener implements OnPageChangeListener
{ |
05 |
|
06 |
int one
= offset * 2 +
bmpW; //
页卡1 -> 页卡2 偏移量 |
07 |
int two
= one * 2 ; //
页卡1 -> 页卡3 偏移量 |
08 |
|
09 |
@Override |
10 |
public void onPageSelected( int arg0)
{ |
11 |
Animation
animation = null ; |
12 |
switch (arg0)
{ |
13 |
case 0 : |
14 |
if (currIndex
== 1 )
{ |
15 |
animation
= new TranslateAnimation(one, 0 , 0 , 0 ); |
16 |
} else if (currIndex
== 2 )
{ |
17 |
animation
= new TranslateAnimation(two, 0 , 0 , 0 ); |
18 |
} |
19 |
break ; |
20 |
case 1 : |
21 |
if (currIndex
== 0 )
{ |
22 |
animation
= new TranslateAnimation(offset,
one, 0 , 0 ); |
23 |
} else if (currIndex
== 2 )
{ |
24 |
animation
= new TranslateAnimation(two,
one, 0 , 0 ); |
25 |
} |
26 |
break ; |
27 |
case 2 : |
28 |
if (currIndex
== 0 )
{ |
29 |
animation
= new TranslateAnimation(offset,
two, 0 , 0 ); |
30 |
} else if (currIndex
== 1 )
{ |
31 |
animation
= new TranslateAnimation(one,
two, 0 , 0 ); |
32 |
} |
33 |
break ; |
34 |
} |
35 |
currIndex
= arg0; |
36 |
animation.setFillAfter( true ); //
True:图片停在动画结束位置 |
37 |
animation.setDuration( 300 ); |
38 |
cursor.startAnimation(animation); |
39 |
} |
40 |
|
41 |
@Override |
42 |
public void onPageScrolled( int arg0, float arg1, int arg2)
{ |
43 |
} |
44 |
|
45 |
@Override |
46 |
public void onPageScrollStateChanged( int arg0)
{ |
47 |
} |
48 |
} |
五、打完收工,快来看看自己的劳动成果吧
Android Tab页面手势滑动切换以及动画效果,布布扣,bubuko.com
原文:http://blog.csdn.net/fancylovejava/article/details/21446321