package com.example.sortlistview; import android.content.Context; import android.graphics.Canvas; import android.graphics.Color; import android.graphics.Paint; import android.graphics.Typeface; import android.graphics.drawable.ColorDrawable; import android.util.AttributeSet; import android.view.MotionEvent; import android.view.View; import android.widget.TextView; public class SideBar extends View { // ����¼� private OnTouchingLetterChangedListener onTouchingLetterChangedListener; // 26����ĸ 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 int choose = -1;// ѡ�� private Paint paint = new Paint(); private TextView mTextDialog; public void setTextView(TextView mTextDialog) { this.mTextDialog = mTextDialog; } public SideBar(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); } public SideBar(Context context, AttributeSet attrs) { super(context, attrs); } public SideBar(Context context) { super(context); } /** * ��д������ */ protected void onDraw(Canvas canvas) { super.onDraw(canvas); // ��ȡ����ı䱳����ɫ. int height = getHeight();// ��ȡ��Ӧ�߶� int width = getWidth(); // ��ȡ��Ӧ��� int singleHeight = height / b.length;// ��ȡÿһ����ĸ�ĸ߶� for (int i = 0; i < b.length; i++) { paint.setColor(Color.rgb(33, 65, 98)); // paint.setColor(Color.WHITE); paint.setTypeface(Typeface.DEFAULT_BOLD); paint.setAntiAlias(true); paint.setTextSize(20); // ѡ�е�״̬ if (i == choose) { paint.setColor(Color.parseColor("#3399ff")); paint.setFakeBoldText(true); } // x�������м�-�ַ�����ȵ�һ��. float xPos = width / 2 - paint.measureText(b[i]) / 2; float yPos = singleHeight * i + singleHeight; canvas.drawText(b[i], xPos, yPos, paint); paint.reset();// ���û��� } } @Override public boolean dispatchTouchEvent(MotionEvent event) { final int action = event.getAction(); final float y = event.getY();// ��y��� final int oldChoose = choose; final OnTouchingLetterChangedListener listener = onTouchingLetterChangedListener; final int c = (int) (y / getHeight() * b.length);// ��y����ռ�ܸ߶ȵı��*b���ij��Ⱦ͵��ڵ�b�еĸ��. switch (action) { case MotionEvent.ACTION_UP: setBackgroundDrawable(new ColorDrawable(0x00000000)); choose = -1;// invalidate(); if (mTextDialog != null) { mTextDialog.setVisibility(View.INVISIBLE); } break; default: setBackgroundResource(R.drawable.sidebar_background); if (oldChoose != c) { if (c >= 0 && c < b.length) { if (listener != null) { listener.onTouchingLetterChanged(b[c]); } if (mTextDialog != null) { mTextDialog.setText(b[c]); mTextDialog.setVisibility(View.VISIBLE); } choose = c; invalidate(); } } break; } return true; } /** * ������ķ��� * * @param onTouchingLetterChangedListener */ public void setOnTouchingLetterChangedListener( OnTouchingLetterChangedListener onTouchingLetterChangedListener) { this.onTouchingLetterChangedListener = onTouchingLetterChangedListener; } /** * �ӿ� * * @author coder * */ public interface OnTouchingLetterChangedListener { public void onTouchingLetterChanged(String s); } }