知识点
1.ViewFlipper基本用法及动态添加View；
2.ViewFlipper结合手势翻页+特效；
3.WindowManager的基本用法。
任意张图片实现循环滑动，其实PageFlipper当前最多的子View个数(ChildViewCount)小于等于2.
<?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:gravity="center" ><ImageView
android:id="@+id/img"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:gravity="center" /></LinearLayout>
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" ><ViewFlipper
android:id="@+id/myViewFlipper"
android:layout_width="fill_parent"
android:layout_height="fill_parent" ></ViewFlipper>
</LinearLayout>
package com.xyz.pagefilter;import android.app.Activity;
import android.content.Context;
import android.graphics.PixelFormat;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.GestureDetector;
import android.view.GestureDetector.OnGestureListener;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
import android.view.Window;
import android.view.WindowManager;
import android.view.WindowManager.LayoutParams;
import android.widget.ImageView;
import android.widget.ViewFlipper;public class MainActivity extends Activity implements OnTouchListener,
OnGestureListener {private LayoutInflater mInflater;
private WindowManager wm = null;
private WindowManager.LayoutParams wmParams = null;private ImageView leftbtn = null;
private ImageView rightbtn = null;private int mAlpha = 0;
private boolean isHide;private int mCurrPos = 0;
private ViewFlipper viewFlipper = null;
private GestureDetector mGestureDetector;private int[] mImages = new int[] { R.drawable.img_0, R.drawable.img_1,
R.drawable.img_2, R.drawable.img_3, R.drawable.img_4,
R.drawable.img_5, R.drawable.img_6, R.drawable.img_7,
R.drawable.img_8, R.drawable.img_9 };@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(R.layout.main);mInflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
viewFlipper = (ViewFlipper) this.findViewById(R.id.myViewFlipper);
setView(mCurrPos, 0);
initFloatView();// viewFlipper.setLongClickable(true);
viewFlipper.setOnTouchListener(this);
mGestureDetector = new GestureDetector(this);}
private void initFloatView() {
wm = (WindowManager) getApplicationContext().getSystemService(
Context.WINDOW_SERVICE);
wmParams = new WindowManager.LayoutParams();wmParams.type = LayoutParams.TYPE_PHONE;
wmParams.format = PixelFormat.RGBA_8888;wmParams.flags = LayoutParams.FLAG_NOT_TOUCH_MODAL
| LayoutParams.FLAG_NOT_FOCUSABLE;wmParams.x = 0;
wmParams.y = 0;wmParams.width = 50;
wmParams.height = 50;createLeftFloatView();
createRightFloatView();
}private void createLeftFloatView() {
leftbtn = new ImageView(this);
leftbtn.setImageResource(R.drawable.prev);
leftbtn.setAlpha(0);
leftbtn.setOnClickListener(new View.OnClickListener() {
public void onClick(View arg0) {
movePrevious();
}
});wmParams.gravity = Gravity.LEFT | Gravity.CENTER_VERTICAL;
wm.addView(leftbtn, wmParams);
}private void createRightFloatView() {
rightbtn = new ImageView(this);
rightbtn.setImageResource(R.drawable.next);
rightbtn.setAlpha(0);
rightbtn.setOnClickListener(new View.OnClickListener() {
public void onClick(View arg0) {
moveNext();
}
});wmParams.gravity = Gravity.RIGHT | Gravity.CENTER_VERTICAL;
wm.addView(rightbtn, wmParams);
}private void setView(int curr, int next) {
View v = (View) mInflater.inflate(R.layout.flipper_item, null);
ImageView iv = (ImageView) v.findViewById(R.id.img);
// iv.setScaleType(ImageView.ScaleType.FIT_XY);
if (curr < next && next > mImages.length - 1)
next = 0;
else if (curr > next && next < 0)
next = mImages.length - 1;
iv.setImageResource(mImages[next]);
if (viewFlipper.getChildCount() > 1) {
viewFlipper.removeViewAt(0);
}
viewFlipper.addView(v, viewFlipper.getChildCount());
mCurrPos = next;}
private void movePrevious() {
setView(mCurrPos, mCurrPos - 1);
viewFlipper.setInAnimation(MainActivity.this, R.anim.in_leftright);
viewFlipper.setOutAnimation(MainActivity.this, R.anim.out_leftright);
viewFlipper.showPrevious();
}private void moveNext() {
setView(mCurrPos, mCurrPos + 1);
viewFlipper.setInAnimation(MainActivity.this, R.anim.in_rightleft);
viewFlipper.setOutAnimation(MainActivity.this, R.anim.out_rightleft);
viewFlipper.showNext();
}private Handler mHandler = new Handler() {
public void handleMessage(Message msg) {
if (msg.what == 1 && mAlpha < 255) {
mAlpha += 50;
if (mAlpha > 255)
mAlpha = 255;
leftbtn.setAlpha(mAlpha);
leftbtn.invalidate();
rightbtn.setAlpha(mAlpha);
rightbtn.invalidate();
if (!isHide && mAlpha < 255)
mHandler.sendEmptyMessageDelayed(1, 100);
} else if (msg.what == 0 && mAlpha > 0) {
mAlpha -= 10;
if (mAlpha < 0)
mAlpha = 0;
leftbtn.setAlpha(mAlpha);
leftbtn.invalidate();
rightbtn.setAlpha(mAlpha);
rightbtn.invalidate();
if (isHide && mAlpha > 0)
mHandler.sendEmptyMessageDelayed(0, 100);
}
}
};private void showFloatView() {
isHide = false;
mHandler.sendEmptyMessage(1);
}private void hideFloatView() {
new Thread() {
public void run() {
try {
Thread.sleep(1500);
isHide = true;
mHandler.sendEmptyMessage(0);
} catch (Exception e) {
}
}
}.start();
}@Override
public void onDestroy() {
super.onDestroy();
wm.removeView(leftbtn);
wm.removeView(rightbtn);
}@Override
public boolean onDown(MotionEvent e) {
return false;
}@Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
float velocityY) {
int x = (int) (e2.getX() - e1.getX());
if (x > 0) {
movePrevious();
} else {
moveNext();
}
return false;
}@Override
public void onLongPress(MotionEvent e) {}
@Override
public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX,
float distanceY) {
return false;
}@Override
public void onShowPress(MotionEvent e) {
// 用户轻触屏幕，尚末松开或拖动，注意，强调的是没有没有松开或者拖动状态
}@Override
public boolean onSingleTapUp(MotionEvent e) {
return false;
}@Override
public boolean onTouch(View v, MotionEvent event) {
switch (event.getAction()) {
case MotionEvent.ACTION_MOVE:
case MotionEvent.ACTION_DOWN:
showFloatView();
break;
case MotionEvent.ACTION_UP:
hideFloatView();
break;
}
mGestureDetector.onTouchEvent(event);
return true;
}
}
附加特效文件：
in_leftright.xml:
<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android" ><translate
android:duration="500"
android:fromXDelta="-100%p"
android:toXDelta="0" /><alpha
android:duration="500"
android:fromAlpha="0.0"
android:toAlpha="1.0" /></set>
in_rightleft.xml:
<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android" >
<translate
android:duration="500"
android:fromXDelta="100%p"
android:toXDelta="0" /><alpha
android:duration="500"
android:fromAlpha="0.0"
android:toAlpha="1.0" />
</set>
out_leftright.xml:
<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android" >
<translate
android:duration="500"
android:fromXDelta="0"
android:toXDelta="100%p" /><alpha
android:duration="500"
android:fromAlpha="1.0"
android:toAlpha="0.0" />
</set>
out_rightleft.xml:
<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android" ><translate
android:duration="500"
android:fromXDelta="0"
android:toXDelta="-100%p" /><alpha
android:duration="500"
android:fromAlpha="1.0"
android:toAlpha="0.0" /></set>
ViewFlipper动态加载View