融合了A~Z快速索引和侧滑菜单的ListVeiw的demo

来源：互联网发布：手机申请淘宝账号编辑：程序博客网时间：2024/05/22 07:01

本demo技术要点

自定义快速索引控件
ViewPager有效的禁止左右滑动
Fragment抽取懒加载基类,且只加载一次
感谢开源库SwipeMenuListView

效果图

快速索引控件.

package cn.evun.view;import android.content.Context;import android.graphics.Canvas;import android.graphics.Color;import android.graphics.Paint;import android.graphics.Rect;import android.util.AttributeSet;import android.view.MotionEvent;import android.view.View;import cn.evun.javebean.Cheeses;/** * 自定义快速索引 */public class QuickIndexBar extends View {    private Paint paint;    private float cellWidth;    private float cellHeight;    public QuickIndexBar(Context context, AttributeSet attrs) {        super(context, attrs);        init();    }    private void init() {        paint = new Paint();        paint.setColor(Color.GRAY);        paint.setTextSize(30);    }    @Override    protected void onDraw(Canvas canvas) {        super.onDraw(canvas);//      canvas.drawText("#",10f,20f,paint);//      canvas.drawText("#",10f,50f,paint);//      canvas.drawText("#",10f,80f,paint);//      canvas.drawText("#",10f,110f,paint);//      canvas.drawText("#",10f,140f,paint);        for (int i = 0; i < Cheeses.LETTERS.length; i++) {            String letter = Cheeses.LETTERS[i];            Rect rect = new Rect();            //获取不同的字母的宽高            //将字母放入一个矩形容器中,矩形容器的宽高就是字母的宽高            //获取文字边界            paint.getTextBounds(letter, 0, 1, rect);            //矩形的宽高就是文本的宽高            int textWidth = rect.width();            int textHeight = rect.height();            float x = cellWidth * 0.5f - textWidth * 0.5f;            float y = cellHeight * 0.5f + textHeight * 0.5f + i * cellHeight;            canvas.drawText(letter, x, y, paint);        }    }    //获取cellWidth和cellHeight    @Override    protected void onSizeChanged(int w, int h, int oldw, int oldh) {        super.onSizeChanged(w, h, oldw, oldh);        //获取当前控件的测量宽高        cellWidth = this.getMeasuredWidth();        cellHeight = this.getMeasuredHeight() * 1.0f / Cheeses.LETTERS.length;    }    //当前索引    private int currentIndex = -1;    //上一个索引    private int lastIndex = -1;    @Override    public boolean onTouchEvent(MotionEvent event) {        switch (event.getAction()) {            case MotionEvent.ACTION_DOWN:            case MotionEvent.ACTION_MOVE:                if (listener != null) {                    //每次滑动前,将当前索引赋值给上一个索引                    lastIndex = currentIndex;                    //目的:找到触摸的位置对应的letter                    float y = event.getY();                    //修改当前索引                    currentIndex = (int) (y / cellHeight);                    if (currentIndex > Cheeses.LETTERS.length - 1) {                        currentIndex = Cheeses.LETTERS.length - 1;                    } else if (currentIndex < 0) {                        currentIndex = 0;                    }                    if (lastIndex != currentIndex) {                        String letter = Cheeses.LETTERS[currentIndex];//                  Log.i("test", "letter:" + letter);                        listener.onLetterChanged(letter);                    }                }                break;            case MotionEvent.ACTION_UP:                if(listener!=null){                    listener.onLetterDismiss();                }                break;        }        //想要处理事件        return true;    }    private OnLetterChangedListener listener;    public interface OnLetterChangedListener {        void onLetterChanged(String letter);        void onLetterDismiss();    }    public void setOnLetterChangedListener(OnLetterChangedListener listener) {        this.listener = listener;    }}

ViewPager有效的禁止左右滑动

package cn.evun.view;import android.content.Context;import android.support.v4.view.ViewPager;import android.util.AttributeSet;import android.view.MotionEvent;/** */public class NoScrollViewPager extends ViewPager {    private boolean canScroll =true;    public NoScrollViewPager(Context context) {        super(context);    }    public NoScrollViewPager(Context context, AttributeSet attrs) {        super(context, attrs);    }    @Override    public boolean onTouchEvent(MotionEvent ev) {        return this.canScroll&&super.onTouchEvent(ev);    }    @Override    public boolean onInterceptTouchEvent(MotionEvent ev) {        return this.canScroll&&super.onInterceptTouchEvent(ev);    }    public void isCanScroll(boolean b){        this.canScroll =b;    }}

源码传送

CSDN下载
Github源码

阅读全文

1 0