1.示意图
2.自己定义控件SwitchView
public class SwitchView extends View {
public static final String TAG = SwitchView.class.getSimpleName();
// 状态
public static final int STATUS_OFF = 0;
public static final int STATUS_ON = 1;
public static final int STATUS_SCROLING = 2;
// 用于显示的文本
private String mOnText = "打开";
private String mOffText = "关闭";
private int mSwitchStatus = STATUS_OFF;
private boolean mHasScrolled = false;// 表示是否发生过滚动
private int mSrcX = 0, mDstX = 0;
private int mBmpWidth = 0;
private int mBmpHeight = 0;
private int mThumbWidth = 0;
private Paint mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
private OnSwitchChangedListener mOnSwitchChangedListener = null;
// 开关状态图
Bitmap mSwitch_off, mSwitch_on, mSwitch_thumb;
public SwitchView(Context context) {
this(context, null);
}
public SwitchView(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
public SwitchView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init();
}
// 初始化三幅图片
private void init() {
Resources res = getResources();
mSwitch_off = BitmapFactory.decodeResource(res, R.drawable.bg_switch_off);
mSwitch_on = BitmapFactory.decodeResource(res, R.drawable.bg_switch_on);
mSwitch_thumb = BitmapFactory.decodeResource(res, R.drawable.switch_thumb);
mBmpWidth = mSwitch_on.getWidth();
mBmpHeight = mSwitch_on.getHeight();
mThumbWidth = mSwitch_thumb.getWidth();
}
@Override
public void setLayoutParams(LayoutParams params) {
params.width = mBmpWidth;
params.height = mBmpHeight;
super.setLayoutParams(params);
}
/**
* 设置监听器
*
*/
public void setOnSwitchChangedListener(OnSwitchChangedListener l) {
mOnSwitchChangedListener = l;
}
/**
* 设置文本
*/
public void setText(final String onText, final String offText) {
mOnText = onText;
mOffText = offText;
invalidate();
}
/**
* 设置开关的状态
*/
public void setStatus(boolean on) {
mSwitchStatus = (on ? STATUS_ON : STATUS_OFF);
}
@Override
public boolean onTouchEvent(MotionEvent event) {
int action = event.getAction();
switch (action) {
case MotionEvent.ACTION_DOWN:
mSrcX = (int) event.getX();
break;
case MotionEvent.ACTION_MOVE:
mDstX = Math.max((int) event.getX(), 10);
mDstX = Math.min(mDstX, 62);
if (mSrcX == mDstX)
return true;
mHasScrolled = true;
AnimationTransRunnable aTransRunnable = new AnimationTransRunnable(mSrcX, mDstX, 0);
new Thread(aTransRunnable).start();
mSrcX = mDstX;
break;
case MotionEvent.ACTION_UP:
if (mHasScrolled == false) {// 假设没有发生过滑动，就意味着这是一次单击过程
mSwitchStatus = Math.abs(mSwitchStatus - 1);
int xFrom = 10, xTo = 62;
if (mSwitchStatus == STATUS_OFF) {
xFrom = 62;
xTo = 10;
}
AnimationTransRunnable runnable = new AnimationTransRunnable(xFrom, xTo, 1);
new Thread(runnable).start();
} else {
invalidate();
mHasScrolled = false;
}
// 状态改变的时候 回调事件函数
if (mOnSwitchChangedListener != null) {
mOnSwitchChangedListener.onSwitchChanged(this, mSwitchStatus);
}
break;
default:
break;
}
return true;
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
// 画图的时候 内部用到了一些数值的硬编码，事实上不太好，
// 主要是考虑到图片的原因，图片周围有透明边界，所以要有一定的偏移
// 硬编码的数值仅仅要看懂了代码，事实上能够理解其含义，能够做对应改进。
mPaint.setTextSize(14);
mPaint.setTypeface(Typeface.DEFAULT_BOLD);
if (mSwitchStatus == STATUS_OFF) {
drawBitmap(canvas, null, null, mSwitch_off);
drawBitmap(canvas, null, null, mSwitch_thumb);
mPaint.setColor(Color.rgb(105, 105, 105));
canvas.translate(mSwitch_thumb.getWidth(), 0);
canvas.drawText(mOffText, 0, 20, mPaint);
} else if (mSwitchStatus == STATUS_ON) {
drawBitmap(canvas, null, null, mSwitch_on);
int count = canvas.save();
canvas.translate(mSwitch_on.getWidth() - mSwitch_thumb.getWidth(), 0);
drawBitmap(canvas, null, null, mSwitch_thumb);
mPaint.setColor(Color.WHITE);
canvas.restoreToCount(count);
canvas.drawText(mOnText, 17, 20, mPaint);
} else { // SWITCH_SCROLING
mSwitchStatus = mDstX > 35 ? STATUS_ON : STATUS_OFF;
drawBitmap(canvas, new Rect(0, 0, mDstX, mBmpHeight), new Rect(0, 0, (int) mDstX, mBmpHeight), mSwitch_on);
mPaint.setColor(Color.WHITE);
canvas.drawText(mOnText, 17, 20, mPaint);
int count = canvas.save();
canvas.translate(mDstX, 0);
drawBitmap(canvas, new Rect(mDstX, 0, mBmpWidth, mBmpHeight),
new Rect(0, 0, mBmpWidth - mDstX, mBmpHeight), mSwitch_off);
canvas.restoreToCount(count);
count = canvas.save();
canvas.clipRect(mDstX, 0, mBmpWidth, mBmpHeight);
canvas.translate(mThumbWidth, 0);
mPaint.setColor(Color.rgb(105, 105, 105));
canvas.drawText(mOffText, 0, 20, mPaint);
canvas.restoreToCount(count);
count = canvas.save();
canvas.translate(mDstX - mThumbWidth / 2, 0);
drawBitmap(canvas, null, null, mSwitch_thumb);
canvas.restoreToCount(count);
}
}
public void drawBitmap(Canvas canvas, Rect src, Rect dst, Bitmap bitmap) {
dst = (dst == null ?
new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight()) : dst);
Paint paint = new Paint();
canvas.drawBitmap(bitmap, src, dst, paint);
}
/**
* AnimationTransRunnable 做滑动动画所使用的线程
*/
private class AnimationTransRunnable implements Runnable {
private int srcX, dstX;
private int duration;
public AnimationTransRunnable(float srcX, float dstX, final int duration) {
this.srcX = (int) srcX;
this.dstX = (int) dstX;
this.duration = duration;
}
@Override
public void run() {
final int patch = (dstX > srcX ?
5 : -5);
if (duration == 0) {
SwitchView.this.mSwitchStatus = STATUS_SCROLING;
SwitchView.this.postInvalidate();
} else {
int x = srcX + patch;
while (Math.abs(x - dstX) > 5) {
mDstX = x;
SwitchView.this.mSwitchStatus = STATUS_SCROLING;
SwitchView.this.postInvalidate();
x += patch;
try {
Thread.sleep(10);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
mDstX = dstX;
SwitchView.this.mSwitchStatus = mDstX > 35 ?
STATUS_ON : STATUS_OFF;
SwitchView.this.postInvalidate();
}
}
}
public static interface OnSwitchChangedListener {
public abstract void onSwitchChanged(SwitchView obj, int status);
}
}