Android UI--开源项目IndexableListView(字母索引）(1)

}

// 获得韩文初始化字符数组里面的一个字符

private static char getInitialSound(char c) {

return KOREAN_INITIAL[(c - KOREAN_UNICODE_START) / KOREAN_UNIT];

}

自定义索引列表

Copyright 2011 woozzu Licensed under the Apache License, Version 2.0 (the “License”); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an “AS IS” BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

package com.wwj.indexableListView.widget;

import android.content.Context;

import android.graphics.Canvas;

import android.util.AttributeSet;

import android.view.GestureDetector;

import android.view.MotionEvent;

import android.widget.ListAdapter;

import android.widget.ListView;

/**

自定义索引列表 @author by 佚名

public class IndexableListView extends ListView {

private boolean mIsFastScrollEnabled = false;

private IndexScroller mScroller = null;

private GestureDetector mGestureDetector = null;

public IndexableListView(Context context) {

super(context);

}

public IndexableListView(Context context, AttributeSet attrs) {

super(context, attrs);

}

public IndexableListView(Context context, AttributeSet attrs, int defStyle) {

super(context, attrs, defStyle);

}

@Override

public boolean isFastScrollEnabled() {

return mIsFastScrollEnabled;

}

@Override

public void setFastScrollEnabled(boolean enabled) {

mIsFastScrollEnabled = enabled;

if (mIsFastScrollEnabled) {

if (mScroller == null)

mScroller = new IndexScroller(getContext(), this);

} else {

if (mScroller != null) {

mScroller.hide();

mScroller = null;

}

@Override

public void draw(Canvas canvas) {

super.draw(canvas);

// Overlay index bar

if (mScroller != null)

mScroller.draw(canvas);

}

@Override

public boolean onTouchEvent(MotionEvent ev) {

// Intercept ListView’s touch event

if (mScroller != null && mScroller.onTouchEvent(ev))

return true;

if (mGestureDetector == null) {

// 创建一个GestureDetector（手势探测器）

mGestureDetector = new GestureDetector(getContext(),

new GestureDetector.SimpleOnGestureListener() {

@Override

public boolean onFling(MotionEvent e1, MotionEvent e2,

float velocityX, float velocityY) {

// If fling happens, index bar shows

// 显示索引条

mScroller.show();

return super.onFling(e1, e2, velocityX, velocityY);

}

});

}

mGestureDetector.onTouchEvent(ev);

return super.onTouchEvent(ev);

}

@Override

public boolean onInterceptTouchEvent(MotionEvent ev) {

return true;

}

@Override

public void setAdapter(ListAdapter adapter) {

super.setAdapter(adapter);

if (mScroller != null)

mScroller.setAdapter(adapter);

}

@Override

protected void onSizeChanged(int w, int h, int oldw, int oldh) {

super.onSizeChanged(w, h, oldw, oldh);

if (mScroller != null)

mScroller.onSizeChanged(w, h, oldw, oldh);

}

索引条

package com.wwj.indexableListView.widget;

import android.content.Context;

import android.graphics.Canvas;

import android.graphics.Color;

import android.graphics.Paint;

import android.graphics.RectF;

import android.os.Handler;

import android.os.Message;

import android.os.SystemClock;

import android.view.MotionEvent;

import android.widget.Adapter;

import android.widget.ListView;

import android.widget.SectionIndexer;

/**

右侧的索引条 @author by 佚名

public class IndexScroller {

private float mIndexbarWidth; // 索引条宽度

private float mIndexbarMargin; // 索引条外边距

private float mPreviewPadding; //

private float mDensity; // 密度

private float mScaledDensity; // 缩放密度

private float mAlphaRate; // 透明度

private int mState = STATE_HIDDEN; // 状态

private int mListViewWidth; // ListView宽度

private int mListViewHeight; // ListView高度

private int mCurrentSection = -1; // 当前部分

private boolean mIsIndexing = false; // 是否正在索引

private ListView mListView = null;

private SectionIndexer mIndexer = null;

private String[] mSections = null;

private RectF mIndexbarRect;

// 4种状态（已隐藏、正在显示、已显示、正在隐藏）

private static final int STATE_HIDDEN = 0;

private static final int STATE_SHOWING = 1;

private static final int STATE_SHOWN = 2;

private static final int STATE_HIDING = 3;

public IndexScroller(Context context, ListView lv) {

mDensity = context.getResources().getDisplayMetrics().density;

mScaledDensity = context.getResources().getDisplayMetrics().scaledDensity;

mListView = lv;

setAdapter(mListView.getAdapter());

mIndexbarWidth = 20 * mDensity; // 索引条宽度

mIndexbarMargin = 10 * mDensity;// 索引条间距

mPreviewPadding = 5 * mDensity; // 内边距

}

public void draw(Canvas canvas) {

if (mState == STATE_HIDDEN)

return;

// mAlphaRate determines the rate of opacity

Paint indexbarPaint = new Paint();

indexbarPaint.setColor(Color.BLACK);

indexbarPaint.setAlpha((int) (64 * mAlphaRate));

indexbarPaint.setAntiAlias(true);

// 画右侧字母索引的圆矩形

canvas.drawRoundRect(mIndexbarRect, 5 * mDensity, 5 * mDensity,

indexbarPaint);

if (mSections != null && mSections.length > 0) {

// Preview is shown when mCurrentSection is set

if (mCurrentSection >= 0) {

Paint previewPaint = new Paint(); // 用来绘画所以条背景的画笔

previewPaint.setColor(Color.BLACK);// 设置画笔颜色为黑色

previewPaint.setAlpha(96); // 设置透明度

previewPaint.setAntiAlias(true);// 设置抗锯齿

previewPaint.setShadowLayer(3, 0, 0, Color.argb(64, 0, 0, 0)); // 设置阴影层

Paint previewTextPaint = new Paint(); // 用来绘画索引字母的画笔

previewTextPaint.setColor(Color.WHITE); // 设置画笔为白色

previewTextPaint.setAntiAlias(true); // 设置抗锯齿

previewTextPaint.setTextSize(50 * mScaledDensity); // 设置字体大小

// 文本的宽度

float previewTextWidth = previewTextPaint

.measureText(mSections[mCurrentSection]);

float previewSize = 2 * mPreviewPadding

previewTextPaint.descent()

previewTextPaint.ascent();

RectF previewRect = new RectF(

(mListViewWidth - previewSize) / 2,

(mListViewHeight - previewSize) / 2,

(mListViewWidth - previewSize) / 2 + previewSize,

(mListViewHeight - previewSize) / 2 + previewSize);

// 中间索引的那个框

canvas.drawRoundRect(previewRect, 5 * mDensity, 5 * mDensity,

previewPaint);

// 绘画索引字母

canvas.drawText(

mSections[mCurrentSection],

previewRect.left + (previewSize - previewTextWidth) / 2

previewRect.top + mPreviewPadding

previewTextPaint.ascent() + 1,

previewTextPaint);

}

// 绘画右侧索引条的字母

Paint indexPaint = new Paint();

indexPaint.setColor(Color.WHITE);

indexPaint.setAlpha((int) (255 * mAlphaRate));

indexPaint.setAntiAlias(true);

indexPaint.setTextSize(12 * mScaledDensity);

float sectionHeight = (mIndexbarRect.height() - 2 * mIndexbarMargin)

/ mSections.length;

float paddingTop = (sectionHeight - (indexPaint.descent() - indexPaint

.ascent())) / 2;

for (int i = 0; i < mSections.length; i++) {

float paddingLeft = (mIndexbarWidth - indexPaint

.measureText(mSections[i])) / 2;

canvas.drawText(mSections[i], mIndexbarRect.left + paddingLeft,

mIndexbarRect.top + mIndexbarMargin + sectionHeight * i

paddingTop - indexPaint.ascent(), indexPaint);

}

public boolean onTouchEvent(MotionEvent ev) {

switch (ev.getAction()) {

case MotionEvent.ACTION_DOWN: // 按下，开始索引

// If down event occurs inside index bar region, start indexing

if (mState != STATE_HIDDEN && contains(ev.getX(), ev.getY())) {

setState(STATE_SHOWN);

// It demonstrates that the motion event started from index bar

mIsIndexing = true;

// Determine which section the point is in, and move the list to

// that section

mCurrentSection = getSectionByPoint(ev.getY());

mListView.setSelection(mIndexer

.getPositionForSection(mCurrentSection));

return true;

}

break;

case MotionEvent.ACTION_MOVE: // 移动

if (mIsIndexing) {

// If this event moves inside index bar

if (contains(ev.getX(), ev.getY())) {

// Determine which section the point is in, and move the

// list to that section

mCurrentSection = getSectionByPoint(ev.getY());

mListView.setSelection(mIndexer

.getPositionForSection(mCurrentSection));

}

return true;

}

break;

case MotionEvent.ACTION_UP: // 抬起

if (mIsIndexing) {

mIsIndexing = false;

mCurrentSection = -1;

}

if (mState == STATE_SHOWN)

setState(STATE_HIDING);

break;

}

return false;

}

public void onSizeChanged(int w, int h, int oldw, int oldh) {

mListViewWidth = w;

mListViewHeight = h;

mIndexbarRect = new RectF(w - mIndexbarMargin - mIndexbarWidth,

mIndexbarMargin, w - mIndexbarMargin, h - mIndexbarMargin);

}

// 显示

public void show() {

if (mState == STATE_HIDDEN)

setState(STATE_SHOWING);

else if (mState == STATE_HIDING)

setState(STATE_HIDING);

}

// 隐藏

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