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本文实例讲述了Android编程实现小说阅读器滑动效果的方法。分享给大家供大家参考，具体如下： 看过小说都知道小说阅读器翻页有好多种效果，比如仿真翻页，滑动翻页，等等。由于某种原因，突然想写一个简单点的滑动翻页效果。在这里写出来也没有什么意图，希望大家可以根据这个效果举一反三，写出其他的效果。图就不上了。 下面是代码：大家理解onTouch事件即可
package com.example.testscroll.view;
import android.content.Context;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.VelocityTracker;
import android.view.View;
import android.view.ViewConfiguration;
import android.view.ViewGroup;
import android.widget.Scroller;
public class FlipperLayout extends ViewGroup {
private Scroller mScroller;
private VelocityTracker mVelocityTracker;
private int mVelocityValue = 0;
/** 商定这个滑动是否有效的距离 */
private int limitDistance = 0;
private int screenWidth = 0;
/** 手指移动的方向 */
private static final int MOVE_TO_LEFT = 0;
private static final int MOVE_TO_RIGHT = 1;
private static final int MOVE_NO_RESULT = 2;
/** 最后触摸的结果方向 */
private int mTouchResult = MOVE_NO_RESULT;
/** 一开始的方向 */
private int mDirection = MOVE_NO_RESULT;
/** 触摸的模式 */
private static final int MODE_NONE = 0;
private static final int MODE_MOVE = 1;
private int mMode = MODE_NONE;
/** 滑动的view */
private View mScrollerView = null;
/** 最上层的view（处于边缘的，看不到的） */
private View currentTopView = null;
/** 显示的view，显示在屏幕 */
private View currentShowView = null;
/** 最底层的view（看不到的） */
private View currentBottomView = null;
public FlipperLayout(Context context) {
super(context);
init(context);
}
public FlipperLayout(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init(context);
}
public FlipperLayout(Context context, AttributeSet attrs) {
super(context, attrs);
init(context);
}
private void init(Context context) {
mScroller = new Scroller(context);
screenWidth = context.getResources().getDisplayMetrics().widthPixels;
limitDistance = screenWidth / 3;
}
/***
*
* @param listener
* @param currentBottomView
* 最底层的view，初始状态看不到
* @param currentShowView
* 正在显示的View
* @param currentTopView
* 最上层的View，初始化时滑出屏幕
*/
public void initFlipperViews(TouchListener listener, View currentBottomView, View currentShowView, View currentTopView) {
this.currentBottomView = currentBottomView;
this.currentShowView = currentShowView;
this.currentTopView = currentTopView;
setTouchResultListener(listener);
addView(currentBottomView);
addView(currentShowView);
addView(currentTopView);
/** 默认将最上层的view滑动的边缘（用于查看（用来判断可滑动性）
*
* @return
*/
public boolean whetherHasNextPage();
}
}
Activity测试文件：
package com.example.testscroll;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import android.app.Activity;
import android.content.res.AssetManager;
import android.os.Bundle;
import android.os.Handler;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.TextView;
import com.example.testscroll.view.FlipperLayout;
import com.example.testscroll.view.FlipperLayout.TouchListener;
import com.example.testscrollactivity.R;
public class MainActivity extends Activity implements OnClickListener, TouchListener {
private String text = "";
private int textLenght = 0;
private static final int COUNT = 400;
private int currentTopEndIndex = 0;
private int currentShowEndIndex = 0;
private int currentBottomEndIndex = 0;
private Handler handler = new Handler() {
public void handleMessage(android.os.Message msg) {
FlipperLayout rootLayout = (FlipperLayout) findViewById(R.id.container);
View recoverView = LayoutInflater.from(MainActivity.this).inflate(R.layout.view_new, null);
View view1 = LayoutInflater.from(MainActivity.this).inflate(R.layout.view_new, null);
View view2 = LayoutInflater.from(MainActivity.this).inflate(R.layout.view_new, null);
rootLayout.initFlipperViews(MainActivity.this, view2, view1, recoverView);
textLenght = text.length();
System.out.println("----textLenght----->" + textLenght);
TextView textView = (TextView) view1.findViewById(R.id.textview);
if (textLenght > COUNT) {
textView.setText(text.subSequence(0, COUNT));
textView = (TextView) view2.findViewById(R.id.textview);
if (textLenght > (COUNT << 1)) {
textView.setText(text.subSequence(COUNT, COUNT * 2));
currentShowEndIndex = COUNT;
currentBottomEndIndex = COUNT << 1;
} else {
textView.setText(text.subSequence(COUNT, textLenght));
currentShowEndIndex = textLenght;
currentBottomEndIndex = textLenght;
}
} else {
textView.setText(text.subSequence(0, textLenght));
currentShowEndIndex = textLenght;
currentBottomEndIndex = textLenght;
}
};
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
new ReadingThread().start();
}
@Override
public void onClick(View v) {
}
@Override
public View createView(final int direction) {
String txt = "";
if (direction == TouchListener.MOVE_TO_LEFT) {
currentTopEndIndex = currentShowEndIndex;
final int nextIndex = currentBottomEndIndex + COUNT;
currentShowEndIndex = currentBottomEndIndex;
if (textLenght > nextIndex) {
txt = text.substring(currentBottomEndIndex, nextIndex);
currentBottomEndIndex = nextIndex;
} else {
txt = text.substring(currentBottomEndIndex, textLenght);
currentBottomEndIndex = textLenght;
}
} else {
currentBottomEndIndex = currentShowEndIndex;
currentShowEndIndex = currentTopEndIndex;
currentTopEndIndex = currentTopEndIndex - COUNT;
txt = text.substring(currentTopEndIndex - COUNT, currentTopEndIndex);
}
View view = LayoutInflater.from(this).inflate(R.layout.view_new, null);
TextView textView = (TextView) view.findViewById(R.id.textview);
textView.setText(txt);
System.out.println("-top->" + currentTopEndIndex + "-show->" + currentShowEndIndex + "--bottom-->" + currentBottomEndIndex);
return view;
}
@Override
public boolean whetherHasPreviousPage() {
return currentShowEndIndex > COUNT;
}
@Override
public boolean whetherHasNextPage() {
return currentShowEndIndex < textLenght;
}
@Override
public boolean currentIsFirstPage() {
boolean should = currentTopEndIndex > COUNT;
if (!should) {
currentBottomEndIndex = currentShowEndIndex;
currentShowEndIndex = currentTopEndIndex;
currentTopEndIndex = currentTopEndIndex - COUNT;
}
return should;
}
@Override
public boolean currentIsLastPage() {
boolean should = currentBottomEndIndex < textLenght;
if (!should) {
currentTopEndIndex = currentShowEndIndex;
final int nextIndex = currentBottomEndIndex + COUNT;
currentShowEndIndex = currentBottomEndIndex;
if (textLenght > nextIndex) {
currentBottomEndIndex = nextIndex;
} else {
currentBottomEndIndex = textLenght;
}
}
return should;
}
private class ReadingThread extends Thread {
public void run() {
AssetManager am = getAssets();
InputStream response;
try {
response = am.open("text.txt");
if (response != null) {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
int i = -1;
while ((i = response.read()) != -1) {
baos.write(i);
}
text = new String(baos.toByteArray(), "UTF-8");
baos.close();
response.close();
handler.sendEmptyMessage(0);
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
xml布局文件： <?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:orientation="horizontal" > <TextView android:id="@+id/textview" android:layout_width="0dp" android:layout_height="match_parent" android:layout_weight="1.0" android:background="#666666" android:gravity="center" android:text="新建的View" android:textColor="@android:color/white" android:textSize="16sp" android:visibility="visible" /> <View android:layout_width="5dp" android:layout_height="match_parent" android:background="#FFFF00" android:gravity="center" android:textSize="25sp" android:visibility="visible" /> </LinearLayout> activity布局文件： <com.example.testscroll.view.FlipperLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:id="@+id/container" android:layout_width="match_parent" android:layout_height="match_parent" > </com.example.testscroll.view.FlipperLayout> 备注：上面为什么加一个速率计算器呢，其实只是为了识别这个动作是不是快速滑动的动作，就算滑动的距离不到屏幕的1/3，但是只要速率满足都可以判定改滑动是一个翻页的动作。 注意哦：这只是其中一个滑动的效果而已啊，不包括小说分章节的逻辑哦。虽然有些粗糙，但是还是有可以值得学习的地方，大家如果还有什么好的解决方案，可以一起讨论。 附上demo下载地址 点击下载demo。 希望本文所述对大家Android程序设计有所帮助。 |