Android 仿 iPhone 自定义滑动按钮(SlipButton)

package com.util; import android.content.Context; import android.graphics.Bitmap; import android.graphics.BitmapFactory; import android.graphics.Canvas; import android.graphics.Matrix; import android.graphics.Paint; import android.graphics.Rect; import android.util.AttributeSet; import android.view.MotionEvent; import android.view.View; import android.view.View.OnTouchListener; import com.view.SlipButton.R; public class SlipButton extends View implements OnTouchListener { private boolean NowChoose = false;// 记录当前按钮是否打开,true为打开,flase为关闭 private boolean isChecked; private boolean OnSlip = false;// 记录用户是否在滑动的变量 private float DownX, NowX;// 按下时的x,当前的x private Rect Btn_On, Btn_Off;// 打开和关闭状态下,游标的Rect . private boolean isChgLsnOn = false; private OnChangedListener ChgLsn; private Bitmap bg_on, bg_off, slip_btn; public SlipButton(Context context) { super(context); init(); } public SlipButton(Context context, AttributeSet attrs) { super(context, attrs); init(); } public SlipButton(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); init(); } private void init() {// 初始化 bg_on = BitmapFactory.decodeResource(getResources(), R.drawable.split_left_1); bg_off = BitmapFactory.decodeResource(getResources(), R.drawable.split_right_1); slip_btn = BitmapFactory.decodeResource(getResources(), R.drawable.split_1); Btn_On = new Rect(0, 0, slip_btn.getWidth(), slip_btn.getHeight()); Btn_Off = new Rect(bg_off.getWidth() - slip_btn.getWidth(), 0, bg_off.getWidth(), slip_btn.getHeight()); setOnTouchListener(this);// 设置监听器,也可以直接复写OnTouchEvent } @Override protected void onDraw(Canvas canvas) {// 绘图函数 super.onDraw(canvas); Matrix matrix = new Matrix(); Paint paint = new Paint(); float x; if (NowX < (bg_on.getWidth() / 2))// 滑动到前半段与后半段的背景不同,在此做判断 { x = NowX - slip_btn.getWidth() / 2; canvas.drawBitmap(bg_off, matrix, paint);// 画出关闭时的背景 } else { x = bg_on.getWidth() - slip_btn.getWidth() / 2; canvas.drawBitmap(bg_on, matrix, paint);// 画出打开时的背景 } if (OnSlip)// 是否是在滑动状态, { if (NowX >= bg_on.getWidth())// 是否划出指定范围,不能让游标跑到外头,必须做这个判断 x = bg_on.getWidth() - slip_btn.getWidth() / 2;// 减去游标1/2的长度... else if (NowX < 0) { x = 0; } else { x = NowX - slip_btn.getWidth() / 2; } } else {// 非滑动状态 if (NowChoose)// 根据现在的开关状态设置画游标的位置 { x = Btn_Off.left; canvas.drawBitmap(bg_on, matrix, paint);// 初始状态为true时应该画出打开状态图片 } else x = Btn_On.left; } if (isChecked) { canvas.drawBitmap(bg_on, matrix, paint); x = Btn_Off.left; isChecked = !isChecked; } if (x < 0)// 对游标位置进行异常判断... x = 0; else if (x > bg_on.getWidth() - slip_btn.getWidth()) x = bg_on.getWidth() - slip_btn.getWidth(); canvas.drawBitmap(slip_btn, x, 0, paint);// 画出游标. } public boolean onTouch(View v, MotionEvent event) { switch (event.getAction()) // 根据动作来执行代码 { case MotionEvent.ACTION_MOVE:// 滑动 NowX = event.getX(); break; case MotionEvent.ACTION_DOWN:// 按下 if (event.getX() > bg_on.getWidth() || event.getY() > bg_on.getHeight()) return false; OnSlip = true; DownX = event.getX(); NowX = DownX; break; case MotionEvent.ACTION_CANCEL: // 移到控件外部 OnSlip = false; boolean choose = NowChoose; if (NowX >= (bg_on.getWidth() / 2)) { NowX = bg_on.getWidth() - slip_btn.getWidth() / 2; NowChoose = true; } else { NowX = NowX - slip_btn.getWidth() / 2; NowChoose = false; } if (isChgLsnOn && (choose != NowChoose)) // 如果设置了监听器,就调用其方法.. ChgLsn.OnChanged(NowChoose); break; case MotionEvent.ACTION_UP:// 松开 OnSlip = false; boolean LastChoose = NowChoose; if (event.getX() >= (bg_on.getWidth() / 2)) { NowX = bg_on.getWidth() - slip_btn.getWidth() / 2; NowChoose = true; } else { NowX = NowX - slip_btn.getWidth() / 2; NowChoose = false; } if (isChgLsnOn && (LastChoose != NowChoose)) // 如果设置了监听器,就调用其方法.. ChgLsn.OnChanged(NowChoose); break; default: } invalidate();// 重画控件 return true; } public void SetOnChangedListener(OnChangedListener l) {// 设置监听器,当状态修改的时候 isChgLsnOn = true; ChgLsn = l; } public interface OnChangedListener { abstract void OnChanged(boolean CheckState); } public void setCheck(boolean isChecked) { this.isChecked = isChecked; NowChoose = isChecked; } }