《Android ViewPager實作Tabhost頁籤底部滑塊動态滑動過渡》
之前基于github上的第三方開源控件ViewPagerIndicator的UnderlinePageIndicator(原文連結:
http://blog.csdn.net/zhangphil/article/details/44752213),自己寫了一個底部帶有滑塊、且當ViewPager頁面切換時候頁籤也随之相應切換,且滑塊也随之相應動态滑動效果得控件。但寫的太過于緊耦合,不利于複用,是以現在重構了代碼,重寫了代碼,把這些效果做成了一個自定制的松耦合控件:TabLinearLayout,該控件可以在未來的項目中直接拿出使用。
控件效果圖如圖所示:
測試用的MainActivity.java:
package zhangphil.view;
import java.util.ArrayList;
import zhangphil.underline.R;
import com.viewpagerindicator.UnderlinePageIndicator;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.v7.app.ActionBarActivity;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.TextView;
import android.content.Context;
import android.graphics.Color;
import android.os.Bundle;
/**
* 基于第三方開源控件ViewPagerIndicator的UnderlinePageIndicator,自己寫的一個在頁籤底部有襯線的滑動控件。
* 控件效果圖如圖所示。 這裡面有一個特别的效果是:頭部的頁籤在ViewPager切換過程中,底部的滑塊也随之動态漸漸滑動過渡。
*
* */
public class MainActivity extends ActionBarActivity {
private TabLinearLayout mTabLinearLayout;
private ArrayList<Fragment> mArryList;
private ViewPager mPager;
// 未被選中的頁籤字型顔色
private int COLOR_NORMAL = Color.DKGRAY;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mArryList = new ArrayList<Fragment>();
// 初始化5個Fragment作為測試。
for (int i = 0; i < 5; i++) {
TestFragment f = (TestFragment) TestFragment.newInstance();
f.id = i;
mArryList.add(f);
}
PagerAdapter mAdapter = new MyFragmentAdapter(
getSupportFragmentManager());
mPager = (ViewPager) findViewById(R.id.pager);
mPager.setAdapter(mAdapter);
UnderlinePageIndicator mIndicator = (UnderlinePageIndicator) findViewById(R.id.indicator);
mIndicator.setViewPager(mPager);
mIndicator.setFades(false);
mIndicator.setSelectedColor(0xff33B5E5);
mTabLinearLayout = (TabLinearLayout) findViewById(R.id.tab_LinearLayout);
ArrayAdapter mTabLinearLayoutAdapter = new MyTabLinearLayoutAdapter(
this, -1);
mTabLinearLayout.initialization(mPager, mTabLinearLayoutAdapter,
mIndicator);
}
private class MyTabLinearLayoutAdapter extends ArrayAdapter {
private Context context;
public MyTabLinearLayoutAdapter(Context context, int resource) {
super(context, resource);
this.context = context;
}
@Override
public int getCount() {
return mArryList.size();
}
// 在這裡僅僅傳回一個TextView作為頁籤的View。
// 此處可以傳回更豐富的View。
@Override
public View getView(int position, View convertView, ViewGroup parent) {
TextView v = new TextView(context);
v.setGravity(Gravity.CENTER);
v.setText("頁籤" + position);
v.setTextColor(COLOR_NORMAL);
return v;
}
}
// 僅僅用于測試的Fragment,用一個id辨別。
private static class TestFragment extends Fragment {
public int id;
public static Fragment newInstance() {
return new TestFragment();
}
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
TextView v = new TextView(getActivity());
v.setGravity(Gravity.CENTER);
v.setTextSize(50f);
v.setText("Fragment: " + id);
return v;
}
}
private class MyFragmentAdapter extends FragmentPagerAdapter {
public MyFragmentAdapter(FragmentManager fm) {
super(fm);
}
@Override
public Fragment getItem(int position) {
return mArryList.get(position);
}
@Override
public int getCount() {
return mArryList.size();
}
}
}
MainActivity.java需要的activity_main.xml布局檔案:
<?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" >
<zhangphil.view.TabLinearLayout
android:id="@+id/tab_LinearLayout"
android:layout_width="match_parent"
android:layout_height="30dip"
android:orientation="horizontal" />
<com.viewpagerindicator.UnderlinePageIndicator
android:id="@+id/indicator"
android:layout_width="match_parent"
android:layout_height="7px" />
<View
android:layout_width="match_parent"
android:layout_height="1px"
android:background="#33B5E5" />
<android.support.v4.view.ViewPager
android:id="@+id/pager"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1" />
</LinearLayout>
自己重寫的TabLinearLayout.java:
package zhangphil.view;
import com.viewpagerindicator.PageIndicator;
import android.content.Context;
import android.graphics.Color;
import android.support.v4.view.ViewPager;
import android.util.AttributeSet;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.LinearLayout;
import android.widget.TextView;
public class TabLinearLayout extends LinearLayout {
private int COLOR_NORMAL = Color.DKGRAY;
private ArrayAdapter mAtapter;
private ViewPager mPager;
private TabLinearLayoutListener mTabLinearLayoutListener;
public TabLinearLayout(Context context, AttributeSet attrs) {
super(context, attrs);
}
public TabLinearLayout(Context context) {
super(context);
}
public void initialization(ViewPager mPager, ArrayAdapter mAtapter,
PageIndicator mPageIndicator) {
this.mAtapter = mAtapter;
this.mPager = mPager;
mPageIndicator
.setOnPageChangeListener(new ViewPager.OnPageChangeListener() {
@Override
public void onPageSelected(int pos) {
setCurrentItem(pos);
if (mTabLinearLayoutListener != null)
mTabLinearLayoutListener.onTab(pos);
}
@Override
public void onPageScrolled(int arg0, float arg1, int arg2) {
}
@Override
public void onPageScrollStateChanged(int arg0) {
}
});
// 添加頁籤
addIndicators();
// 初始化,第0項被選中
setIndicatorViewSelected(0);
}
public void initialization(ViewPager mPager, ArrayAdapter mAtapter,
PageIndicator mPageIndicator,
TabLinearLayoutListener mTabLinearLayoutListener) {
this.mTabLinearLayoutListener = mTabLinearLayoutListener;
initialization(mPager, mAtapter, mPageIndicator);
}
// 添加Tab頁籤
private void addIndicators() {
for (int i = 0; i < mAtapter.getCount(); i++) {
View v = mAtapter.getView(i, null, null);
addIndicatorItem(v, i);
}
}
// 在這裡設定被選中時候頁籤變化的效果
private void setIndicatorViewSelected(int pos) {
for (int i = 0; i < super.getChildCount(); i++) {
if (i == pos) {
View v = super.getChildAt(i);
TextView tv = (TextView) v;
// Android Holo 樣式的藍色
tv.setTextColor(0xff33B5E5);
} else {
View v = super.getChildAt(i);
TextView tv = (TextView) v;
tv.setTextColor(COLOR_NORMAL);
}
}
}
// 線上性布局裡面依次添加一個View,為添加的View添加事件。
private void addIndicatorItem(View view, final int index) {
LayoutParams params = new LayoutParams(LayoutParams.WRAP_CONTENT,
LayoutParams.MATCH_PARENT, 1);
super.addView(view, index, params);
view.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// 當使用者點選該View時候,設定ViewPager正确而Pager Item
if (mTabLinearLayoutListener != null)
mTabLinearLayoutListener.onTab(v, index);
// 設定ViewPager的顯示項。
mPager.setCurrentItem(index, true);
setCurrentItem(index);
}
});
}
// 設定目前LinearLayout的pos項子view被選中。
public void setCurrentItem(int pos) {
setIndicatorViewSelected(pos);
}
// 一個接口,當使用者點選頁籤時候,方法被回調。
public interface TabLinearLayoutListener {
public void onTab(View v, int pos);
public void onTab(int pos);
}
}