我有一个ViewPager,我在其中使用getPageTitle方法来获取当前页面的标题.
这是适配器代码：
@Override
public Fragment getItem(int i) {
details = productData.get(i);
Fragment fragment = new ProductViewFragment();
Bundle args = new Bundle();
args.putInt(ProductViewFragment.ARG_SECTION_NUMBER,i + 1);
fragment.setArguments(args);
return fragment;
}
@Override
public int getCount() {
return productData.size();
}
public CharSequence getPageTitle(int position)
{
return (position+1)+" of "+myData.size();
}
现在我想更新上一个和下一个片段的页面标题.我想将它们命名为“prevIoUs”和“next”.它也应该在后续页面上动态更新.
我能够获得当前页面标题号.例如,当我查看第5个片段时,当前片段将正确显示标题.在ViewPager的两个角上,它显示左侧的上一页标题编号和右侧的下一页标题编号.现在,我希望左侧的“上一个”和右侧的“下一个”页面标题类似于Gmail应用程序以及它如何显示ViewPager中的邮件计数.
解决方法
我的基础是ViewPagerIndicator附带的样本.
您基本上在页面更改时监听,并告诉适配器根据当前位置显示不同的页面标题.
如果你有这些样本工作,你只需要替换这两个文件,然后尝试样本标题 – >默认,它对我来说工作正常…
更改了TestFragmentAdapter的代码,如下所示：
package com.viewpagerindicator.sample;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import com.viewpagerindicator.IconPagerAdapter;
class TestFragmentAdapter extends FragmentPagerAdapter implements IconPagerAdapter {
protected static final String[] CONTENT = new String[] { "This","Is","A","Test",};
protected static final int[] ICONS = new int[] {
R.drawable.perm_group_calendar,R.drawable.perm_group_camera,R.drawable.perm_group_device_alarms,R.drawable.perm_group_location
};
private int mCount = CONTENT.length;
// CHANGE STARTS HERE
private int current_position=0;
public void set_current_position(int i) {
current_position = i;
}
// CHANGE ENDS HERE
public TestFragmentAdapter(FragmentManager fm) {
super(fm);
}
@Override
public Fragment getItem(int position) {
return TestFragment.newInstance(CONTENT[position % CONTENT.length]);
}
@Override
public int getCount() {
return mCount;
}
@Override
public CharSequence getPageTitle(int position) {
// CHANGE STARTS HERE
if (position == current_position-1) {
return "PrevIoUs";
} else if (position == current_position+1) {
return "Next";
}
// CHANGE ENDS HERE
return TestFragmentAdapter.CONTENT[position % CONTENT.length];
}
@Override
public int getIconResId(int index) {
return ICONS[index % ICONS.length];
}
public void setCount(int count) {
if (count > 0 && count <= 10) {
mCount = count;
notifyDataSetChanged();
}
}
}
SampleTitlesDefault的代码如下所示(添加了OnPageChangeListener)
package com.viewpagerindicator.sample;
import android.os.Bundle;
import android.support.v4.view.ViewPager;
import com.viewpagerindicator.TitlePageIndicator;
// CHANGE ADDED implements.... HERE
public class SampleTitlesDefault extends BaseSampleActivity implements ViewPager.OnPageChangeListener {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.simple_titles);
mAdapter = new TestFragmentAdapter(getSupportFragmentManager());
mPager = (ViewPager)findViewById(R.id.pager);
mPager.setAdapter(mAdapter);
mIndicator = (TitlePageIndicator)findViewById(R.id.indicator);
mIndicator.setViewPager(mPager);
// CHANGE STARTS HERE
mIndicator.setOnPageChangeListener(this);
// CHANGE ENDS HERE
}
// CHANGE STARTS HERE
@Override
public void onPageScrolled(int i,float v,int i1) {
}
@Override
public void onPageSelected(int i) {
mPager = (ViewPager)findViewById(R.id.pager);
((TestFragmentAdapter)mPager.getAdapter()).set_current_position(i);
}
@Override
public void onPageScrollStateChanged(int i) {
}
// CHANGE ENDS HERE
}
