Question

我有一个带有五个屏幕图像的Android View寻呼机，带有计时器的自动加载寻呼机屏幕。当用户滑动时，它会根据计时器跳转屏幕，并且无法正确加载。

我在下面附上了代码。

MainActivity.java

package com.sks.androidviewpager;
import java.util.Timer;
import java.util.TimerTask; 
import com.androidsurya.androidviewpager.R; 
import android.app.Activity;
import android.os.Bundle;
import android.support.v4.view.ViewPager;
import android.view.Menu;
public class MainActivity extends Activity {
    int noofsize = 5;
    ViewPager myPager = null;
    int count = 0;
    Timer timer;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);             
        //set the layout which is containg viewPager Tag for image
        setContentView(R.layout.activity_main); 

        //ViewPager Adapter to set image
        ViewPagerAdapter adapter = new ViewPagerAdapter(MainActivity.this,noofsize);
        myPager = (ViewPager) findViewById(R.id.reviewpager);
        myPager.setAdapter(adapter);
        myPager.setCurrentItem(0);

        // Timer for auto sliding
        timer  = new Timer();
        timer.schedule(new TimerTask() {
            @Override
            public void run() {
                runOnUiThread(new Runnable() {
                    @Override
                    public void run() {
                        if(count<=5){
                            myPager.setCurrentItem(count);
                            count++;
                            }else{
                                count = 0;
                                myPager.setCurrentItem(count);
                            }
                    }
                });
            }
        }, 500, 3000);
    }

}

ViewPagerAdapter.java

package com.sks.androidviewpager; 
import com.androidsurya.androidviewpager.R; 
import android.app.Activity;
import android.content.Context;
import android.graphics.Color;
import android.os.Parcelable;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView; 
public class ViewPagerAdapter extends PagerAdapter {
       int size;
       Activity act;
       View layout;
       TextView pagenumber1,pagenumber2,pagenumber3,pagenumber4,pagenumber5;
       ImageView pageImage;
       Button click; 
       public ViewPagerAdapter(MainActivity mainActivity, int noofsize) {
              // TODO Auto-generated constructor stub
              size = noofsize;
              act = mainActivity;
       }
        @Override
       public int getCount() {
              // TODO Auto-generated method stub
              return size;
       }
        @Override
       public Object instantiateItem(View container, int position) {
              // TODO Auto-generated method stub
              LayoutInflater inflater = (LayoutInflater) act
                           .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
              layout = inflater.inflate(R.layout.pages, null);
              pagenumber1 = (TextView)layout.findViewById(R.id.pagenumber1);
              pagenumber2 = (TextView)layout.findViewById(R.id.pagenumber2);
              pagenumber3 = (TextView)layout.findViewById(R.id.pagenumber3);
              pagenumber4 = (TextView)layout.findViewById(R.id.pagenumber4);
              pagenumber5 = (TextView)layout.findViewById(R.id.pagenumber5);
              pageImage = (ImageView)layout.findViewById(R.id.imageView1);
              int pagenumberTxt=position + 1;
              //pagenumber1.setText("Now your in Page No  " +pagenumberTxt );

              try {
                     if(pagenumberTxt == 1){
                           pageImage.setBackgroundResource(R.drawable.android_1);
                           pagenumber1.setTextColor(Color.RED);
                           pagenumber2.setTextColor(Color.WHITE);
                           pagenumber3.setTextColor(Color.WHITE);
                           pagenumber4.setTextColor(Color.WHITE);
                           pagenumber5.setTextColor(Color.WHITE);
                     }
                     else if(pagenumberTxt == 2){
                           pageImage.setBackgroundResource(R.drawable.android_2);
                           pagenumber1.setTextColor(Color.WHITE);
                           pagenumber2.setTextColor(Color.RED);
                           pagenumber3.setTextColor(Color.WHITE);
                           pagenumber4.setTextColor(Color.WHITE);
                           pagenumber5.setTextColor(Color.WHITE);
                     }else if(pagenumberTxt == 3){
                           pageImage.setBackgroundResource(R.drawable.android_3);
                           pagenumber1.setTextColor(Color.WHITE);
                           pagenumber2.setTextColor(Color.WHITE);
                           pagenumber3.setTextColor(Color.RED);
                           pagenumber4.setTextColor(Color.WHITE);
                           pagenumber5.setTextColor(Color.WHITE);
                     }
                     else if(pagenumberTxt == 4){
                           pageImage.setBackgroundResource(R.drawable.android_4);
                           pagenumber1.setTextColor(Color.WHITE);
                           pagenumber2.setTextColor(Color.WHITE);
                           pagenumber3.setTextColor(Color.WHITE);
                           pagenumber4.setTextColor(Color.RED);
                           pagenumber5.setTextColor(Color.WHITE);
                     }
                     else if(pagenumberTxt == 5){
                           pageImage.setBackgroundResource(R.drawable.android_5);
                           pagenumber1.setTextColor(Color.WHITE);
                           pagenumber2.setTextColor(Color.WHITE);
                           pagenumber3.setTextColor(Color.WHITE);
                           pagenumber4.setTextColor(Color.WHITE);
                           pagenumber5.setTextColor(Color.RED);
                     }
              } catch (Exception e) {
                     // TODO Auto-generated catch block
                     e.printStackTrace();
              }

              ((ViewPager) container).addView(layout, 0);
              return layout;
       }
        @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;
       }

       // }
}

activity_main.xml中

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity" > 
    <RelativeLayout
        android:id="@+id/relativeTextview"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:layout_below="@+id/header"
        android:padding="5dp" > 
        <android.support.v4.view.ViewPager
            android:id="@+id/reviewpager"
            android:layout_width="fill_parent"
            android:layout_height="fill_parent" />
    </RelativeLayout>
</RelativeLayout>

pages.xml中

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent" > 
    <ImageView
        android:id="@+id/imageView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:background="@drawable/android_3"
        android:contentDescription="@string/app_name" /> 
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:gravity="bottom|center" > 
        <TextView
            android:id="@+id/pagenumber1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_margin="10dp"
            android:background="#000"
            android:onClick="pageOneClick"
            android:text=" 1 "
            android:textColor="#fff"
            android:textSize="14sp"
            android:textStyle="bold" /> 
        <TextView
            android:id="@+id/pagenumber2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_margin="10dp"
            android:background="#000"
            android:textColor="#fff"
            android:text=" 2 "
            android:textSize="14sp"
            android:textStyle="bold" /> 
        <TextView
            android:id="@+id/pagenumber3"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_margin="10dp"
            android:background="#000"
            android:textColor="#fff"
            android:text=" 3 "
            android:textSize="14sp"
            android:textStyle="bold" /> 
        <TextView
            android:id="@+id/pagenumber4"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_margin="10dp"
            android:background="#000"
            android:textColor="#fff"
            android:text=" 4 "
            android:textSize="14sp"
            android:textStyle="bold" />
         <TextView
            android:id="@+id/pagenumber5"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_margin="10dp"
            android:background="#000"
            android:textColor="#fff"
            android:text=" 5 "
            android:textSize="14sp"
            android:textStyle="bold" />
    </LinearLayout> 
</FrameLayout>

Answer 1

使用 myPager.setCurrentItem(myPager.getCurrentItem()+1); 而不是myPager.setCurrentItem(count);

您应该判断当前项目是否是此视图寻呼机的最后一项。

用户在Android中滑动时，ViewPager无法正确加载

1 个答案: