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package com.qefee.pj.testviewpager;
import android.graphics.Color;
import android.os.Bundle;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
public class MainActivity extends AppCompatActivity {
* log tag for MainActivity
*/
private static final String TAG = "MainActivity";
ViewPager viewPager;
String[] texts = {
"hello",
"world",
"1",
"2"
};
TextView[] textViews;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
int size = initSize();
initTextViews(size);
initViewPager();
}
private void initViewPager() {
viewPager = (ViewPager) findViewById(R.id.viewPage);
viewPager.setAdapter(new PagerAdapter() {
@Override
public int getCount() {
return Integer.MAX_VALUE;
}
@Override
public boolean isViewFromObject(View view, Object object) {
return view == object;
}
@Override
public Object instantiateItem(ViewGroup container, int position) {
Log.i(TAG, "instantiateItem: instantiateItem + position = " + position);
TextView t = textViews[position % textViews.length];
container.addView(t);
return t;
}
@Override
public void destroyItem(ViewGroup container, int position, Object object) {
Log.i(TAG, "destroyItem: + position = " + position);
container.removeView((View) object);
}
});
viewPager.setCurrentItem(texts.length * 1000000);
}
private void initTextViews(int size) {
TextView[] tvs = new TextView[size];
for (int i = 0; i < tvs.length; i++) {
tvs[i] = new TextView(this);
tvs[i].setText(texts[i % texts.length]);
int color = 0;
switch (i % texts.length) {
case 0:
color = Color.parseColor("#aaaaaa");
break;
case 1:
color = Color.parseColor("#cccccc");
break;
case 2:
color = Color.parseColor("#777777");
break;
case 3:
color = Color.parseColor("#999999");
break;
default:
break;
}
tvs[i].setBackgroundColor(color);
ViewGroup.LayoutParams layoutParams = new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT);
tvs[i].setLayoutParams(layoutParams);
textViews = tvs;
}
}
private int initSize() {
int size;
if (texts.length > 3) {
size = texts.length;
} else {
size = texts.length * 2;
}
return size;
}
}
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