本文实例讲述了Android实现仿通讯录侧边栏滑动SiderBar效果代码。分享给大家供大家参考，具体如下：
之前看到某些应用的侧边栏做得不错，想想自己也弄一个出来，现在分享出来，当然里面还有不足的地方，请大家多多包涵。
先上图：
具体实现的代码如下：
package com.freesonfish.listview_index;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
public class MySideBar extends View {
private OnTouchingLetterChangedListener touchListener;
// 26个字母
public static String[] b = { "#", "A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T",
"U", "V", "W", "X", "Y", "Z" };
private boolean showBkg = false;
int choose = -1;
int scrollChoose = -1;
Paint paint = new Paint();
Paint rectPaint = new Paint();
float rectWidth = 0f;
public MySideBar(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init();
}
public MySideBar(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
public MySideBar(Context context) {
super(context);
init();
}
private void init() {
rectPaint.setColor(Color.parseColor("#CCCCCC"));
rectWidth = paint.measureText("#");
}
/**
* 重写这个方法
*/
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
if (showBkg) {
canvas.drawColor(Color.parseColor("#CCCCCC"));
}
final int height = getHeight();
final int width = getWidth();
final int singleHeight = height / b.length;
final float xRectPos = ((float) width - paint.measureText("#")) / 2.0f - rectWidth;
final float xRectPos2 = xRectPos + 3.0f * rectWidth;
for (int i = 0; i < b.length; i++) {
paint.setFakeBoldText(true);
paint.setAntiAlias(true);
final float xPos = ((float) width - paint.measureText(b[i])) / 2.0f;
final float yPos = singleHeight * i + singleHeight;
if (i == choose) {
paint.setColor(Color.RED);
canvas.drawRect(xRectPos, yPos - singleHeight / 2.0f, xRectPos2, yPos + rectWidth, rectPaint);
}
canvas.drawText(b[i], xPos, yPos, paint);
paint.reset();
}
}
@Override
public boolean dispatchTouchEvent(MotionEvent event) {
final int action = event.getAction();
final float y = event.getY();
final int c = (int) (y / getHeight() * b.length);
switch (action) {
case MotionEvent.ACTION_DOWN:
showBkg = true;
if (choose != c && touchListener != null) {
doOnActionDown(c);
}
break;
case MotionEvent.ACTION_MOVE:
if (choose != c && touchListener != null) {
doOnActionDown(c);
}
break;
case MotionEvent.ACTION_UP:
showBkg = false;
invalidate();
break;
}
return true;
}
/**
* listview滚动时候调用它
*
* @param c
*/
public void setColorWhenListViewScrolling(int c) {
if (scrollChoose != c) {
scrollChoose = c;
String string = ListContantsUtil.AbcList.get(c);
for (int i = c; i < b.length; ++i) {
if (string.equals(b[i])) {
choose = i;
invalidate();
break;
}
}
}
}
/**
* 当侧边栏被按下的动作
* @param c
*/
private void doOnActionDown(int c) {
if (c > 0 && c < b.length) {
if (ListContantsUtil.indexPositionMap.containsKey(b[c])) {
touchListener.onTouchingLetterChanged(b[c]);
choose = c;
invalidate();
} else {
c = c - 1;
doOnActionDown(c);
}
}
}
@Override
public boolean onTouchEvent(MotionEvent event) {
return super.onTouchEvent(event);
}
public void setOnTouchingLetterChangedListener(OnTouchingLetterChangedListener touchListener) {
this.touchListener = touchListener;
}
/**
* 用来通知activity显示选中的字母
* @author freeson
*
*/
public interface OnTouchingLetterChangedListener {
public void onTouchingLetterChanged(String s);
}
}
然后ListContantsUtil类是存储通讯录名字的拼音等的类，具体也如下：
package com.freesonfish.listview_index;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
public class ListContantsUtil {
static final List<Integer> indexPositionList = new ArrayList<Integer>();
static final List<String> AbcList = new ArrayList<String>();
static final HashMap<String, Integer> indexPositionMap = new HashMap<String, Integer>();
static void putNameIndexToMap(List<String> list, HashMap<String, String> nameAndPinyin) {
int lenght = list.size();
for (int i = 0; i < lenght; ++i) {
String name = nameAndPinyin.get(list.get(i)).substring(0, 1);
// 判断该字符是属于字母还是数字或其他的
int ascii = name.toCharArray()[0];
if (ascii >= 65 && ascii <= 90) {
if (!indexPositionMap.containsKey(name)) {
indexPositionMap.put(name, i);
AbcList.add(name);
indexPositionList.add(i);
}
} else {
if (!indexPositionMap.containsKey("#")) {
indexPositionMap.put("#", i);
AbcList.add("#");
indexPositionList.add(i);
}
}
}
}
}
注意，上面的程序还是有些小问题的，请大家注意优化解决。
完整实例代码代码点击此处本站下载。
希望本文所述对大家Android程序设计有所帮助。
