Android 为什么viewpager滑动速度慢?
我有一个Android 为什么viewpager滑动速度慢?,android,android-layout,android-viewpager,Android,Android Layout,Android Viewpager,我有一个ViewPager和layouts。布局有大约30张图片,左右滑动是正常的,但从最后一页滑动到第一页速度较慢 它很慢 if (position == 0){ ViewPager myPager = (ViewPager) findViewById(R.id.myfivepanelpager); myPager.setCurrentItem(pageCount-2,false); } else if (position == pageCount-1){ ViewPage
ViewPager
和layouts
。布局有大约30张图片,左右滑动是正常的,但从最后一页滑动到第一页速度较慢
它很慢
if (position == 0){
ViewPager myPager = (ViewPager) findViewById(R.id.myfivepanelpager);
myPager.setCurrentItem(pageCount-2,false);
} else if (position == pageCount-1){
ViewPager myPager = (ViewPager) findViewById(R.id.myfivepanelpager);
myPager.setCurrentItem(1,false);
}
非常感谢
Mypageradapter
package com.example.pictures;
import android.content.Context;
import android.media.AudioManager;
import android.os.Parcelable;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.view.LayoutInflater;
import android.view.View;
public class MyPagerAdapter extends PagerAdapter{
public int getCount() {
return 30;
}
public Object instantiateItem(View collection, int position) {
View view=null;
LayoutInflater inflater = (LayoutInflater) collection.getContext()
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
int resId = 0;
switch (position) {
case 0:
resId = R.layout.picture1;
view = inflater.inflate(resId, null);
break;
case 1:
resId = R.layout.picture2;
view = inflater.inflate(resId, null);
break;
case 2:
resId = R.layout.picture3;
view = inflater.inflate(resId, null);
break;
case 3:
resId = R.layout.picture4;
view = inflater.inflate(resId, null);
break;
case 4:
resId = R.layout.picture5;
view = inflater.inflate(resId, null);
break;
case 5:
resId = R.layout.picture6;
view = inflater.inflate(resId, null);
break;
.....
.....
}
((ViewPager) collection).addView(view, 0);
return view;
}
@SuppressWarnings("unused")
private Context getApplicationContext() {
// TODO Auto-generated method stub
return null;
}
private void setVolumeControlStream(int streamMusic) {
// TODO Auto-generated method stub
}
@SuppressWarnings("unused")
private Context getBaseContext() {
// TODO Auto-generated method stub
return null;
}
@SuppressWarnings("unused")
private PagerAdapter findViewById(int myfivepanelpager) {
// TODO Auto-generated method stub
return null;
}
@Override
public void destroyItem(View arg0, int arg1, Object arg2) {
((ViewPager) arg0).removeView((View) arg2);
}
@Override
public boolean isViewFromObject(View arg0, Object arg1) {
return arg0 == ((View) arg1);
}
@Override
public Parcelable saveState() {
return null;
}
public static Integer getItem(int position) {
// TODO Auto-generated method stub
return null;
}
}
OnPageChangeListener
package com.example.pictures;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.support.v4.view.ViewPager;
import android.support.v4.view.ViewPager.OnPageChangeListener;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;
public class Pictures extends Activity implements OnPageChangeListener{
SoundManager snd;
int sound1,sound2,sound3;
View view=null;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.picturespage);
MyPagerAdapter adapter = new MyPagerAdapter();
ViewPager myPager = (ViewPager) findViewById(R.id.myfivepanelpager);
myPager.setAdapter(adapter);
myPager.setCurrentItem(15);
myPager.setOnPageChangeListener(this);
snd = new SoundManager(this);
sound1 = snd.load(R.raw.sound1);
sound2 = snd.load(R.raw.sound2);
sound3 = snd.load(R.raw.sound3);
}
public void onPageScrollStateChanged(int arg0) {
// TODO Auto-generated method stub
}
public void onPageScrolled(int arg0, float arg1, int arg2) {
// TODO Auto-generated method stub
}
public void onPageSelected(int position) {
// TODO Auto-generated method stub
int pageCount = getCount();
if (position == 0){
ViewPager myPager = (ViewPager) findViewById(R.id.myfivepanelpager);
myPager.setCurrentItem(pageCount-2,false);
} else if (position == pageCount-1){
ViewPager myPager = (ViewPager) findViewById(R.id.myfivepanelpager);
myPager.setCurrentItem(1,false);
}
switch (position) {
case 0:
break;
case 1:
snd.play(sound1);
break;
case 2:
snd.play(sound2);
break;
case 3:
snd.play(sound3);
break;
case 4:
Toast.makeText(this, "4", Toast.LENGTH_SHORT).show();
break;
case 5:
Toast.makeText(this, "5", Toast.LENGTH_SHORT).show();
break;
....
....
}
}
public int getCount() {
return count;
}
};
您不需要每次在onPageSelected中调用ViewPager myPager=(ViewPager)findViewById(R.id.myfivepanelpager),只需在onCreate中调用。将ViewPager myPager设置为类字段,并在所有活动方法中使用相同的对象。请删除
实例化项中的switch语句
,不需要它。只要动态地获取资源id——在我的头顶上,它会像intresid=getResources().getIdentifier(“picture”+(position+1),“layout”,getPackageName())代码>。我该怎么做,您能举个例子吗,我想用picture1-->播放声音1,picture2-->播放声音2…您应该删除这两个switch语句,因为它们是非常冗余的。在instantiateItem
中,只需像我说的那样获取resId,然后编写view=inflater.inflate(resId,null)代码>在它之后。在onPageSelected
中,使用getResources().getIdentifier
以相同的方式加载正确的声音文件。