Android 自定义View实现单击和双击事件

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自定义View,

1. 自定义一个Runnable线程TouchEventCountThread , 用来统计500ms内的点击次数

2. 在MyView中的 onTouchEvent 中调用上面的线程

3. 自定义一个Handler, 在TouchEventHandler 中处理统计到的点击事件, 单击, 双击, 三击, 都可以处理

核心代码如下:

public class MyView extends View { ...... // 统计500ms内的点击次数
TouchEventCountThread mInTouchEventCount = new TouchEventCountThread();
// 根据TouchEventCountThread统计到的点击次数, perform单击还是双击事件
TouchEventHandler mTouchEventHandler = new TouchEventHandler(); @Override
public boolean onTouchEvent(MotionEvent event) {
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
if (0 == mInTouchEventCount.touchCount) // 第一次按下时,开始统计
postDelayed(mInTouchEventCount, 500);
break;
case MotionEvent.ACTION_UP:
// 一次点击事件要有按下和抬起, 有抬起必有按下, 所以只需要在ACTION_UP中处理
mInTouchEventCount.touchCount++;
// 如果是长按操作, 则Handler的消息,不能将touchCount置0, 需要特殊处理
if(mInTouchEventCount.isLongClick) {
mInTouchEventCount.touchCount = 0;
mInTouchEventCount.isLongClick = false;
}
break;
case MotionEvent.ACTION_MOVE:
break;
case MotionEvent.ACTION_CANCEL:
break;
default:
break;
} return super.onTouchEvent(event);
} public class TouchEventCountThread implements Runnable {
public int touchCount = 0;
public boolean isLongClick = false; @Override
public void run() {
Message msg = new Message();
if(0 == touchCount){ // long click
isLongClick = true;
} else {
msg.arg1 = touchCount;
mTouchEventHandler.sendMessage(msg);
touchCount = 0;
}
}
} public class TouchEventHandler extends Handler { @Override
public void handleMessage(Message msg) {
Toast.makeText(mContext, "touch " + msg.arg1 + " time.", Toast.LENGTH_SHORT).show();
}
} ......}

包装以后如下, 这样就能在别的地方调用了:

public interface OnDoubleClickListener{
void onDoubleClick(View v);
} private OnDoubleClickListener mOnDoubleClickListener; public void setOnDoubleClickListener(MyView.OnDoubleClickListener l) {
mOnDoubleClickListener = l;
} public boolean performDoubleClick() {
boolean result = false;
if(mOnDoubleClickListener != null) {
mOnDoubleClickListener.onDoubleClick(this);
result = true;
}
return result;
} public class TouchEventHandler extends Handler { @Override
public void handleMessage(Message msg) {
if(2 == msg.arg1)
performDoubleClick();
}
}

在Activity中使用:

myView1.setOnDoubleClickListener(new MyView.OnDoubleClickListener() {
@Override
public void onDoubleClick(View v) {
Toast.makeText(mContext,"double click", Toast.LENGTH_SHORT).show();
}
});

全部代码

MyView.java

package com.carloz.test.myapplication.view;import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.os.Handler;
import android.os.Message;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import android.widget.Toast;import com.carloz.test.myapplication.R;/**
* Created by root on 15-11-9.
*/
public class MyView extends View { private Paint mPaint = new Paint();
private boolean mNotDestroy = true;
private int mCount = 0;
private MyThread myThread;
Bitmap bitmap;
// attrs
private String mText;
private boolean mStartChange;
Context mContext; public MyView(Context context) {
super(context);
init();
} public MyView(Context context, AttributeSet attrs) {
super(context, attrs);
TypedArray ta = context.obtainStyledAttributes(attrs, R.styleable.MyView);
mText = ta.getString(R.styleable.MyView_text);
mStartChange = ta.getBoolean(R.styleable.MyView_startChange, false);
// Log.d("ASDF", "mText=" + mText + ", mStartChange=" + mStartChange);
ta.recycle(); init();
} @Override
protected void onFinishInflate() {
super.onFinishInflate();
} @Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
} @Override
protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
super.onLayout(changed, left, top, right, bottom);
} @Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
mPaint.setTextSize(50);
canvas.drawText(mText + mCount++, 20f, 100f, mPaint);
canvas.save();
canvas.rotate(60, getWidth() / 2, getHeight() / 2);
canvas.drawBitmap(bitmap, 20f, 50f, mPaint);
canvas.restore(); if (null == myThread) {
myThread = new MyThread();
myThread.start();
}
} @Override
public boolean dispatchTouchEvent(MotionEvent ev) {
return super.dispatchTouchEvent(ev);
} @Override
protected void onAttachedToWindow() {
super.onAttachedToWindow();
mNotDestroy = true;
} @Override
protected void onDetachedFromWindow() {
mNotDestroy = false;
super.onDetachedFromWindow();
} // 统计500ms内的点击次数
TouchEventCountThread mInTouchEventCount = new TouchEventCountThread();
// 根据TouchEventCountThread统计到的点击次数, perform单击还是双击事件
TouchEventHandler mTouchEventHandler = new TouchEventHandler(); @Override
public boolean onTouchEvent(MotionEvent event) {
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
if (0 == mInTouchEventCount.touchCount) // 第一次按下时,开始统计
postDelayed(mInTouchEventCount, 500);
break;
case MotionEvent.ACTION_UP:
// 一次点击事件要有按下和抬起, 有抬起必有按下, 所以只需要在ACTION_UP中处理
mInTouchEventCount.touchCount++;
// 如果是长按操作, 则Handler的消息,不能将touchCount置0, 需要特殊处理
if(mInTouchEventCount.isLongClick) {
mInTouchEventCount.touchCount = 0;
mInTouchEventCount.isLongClick = false;
}
break;
case MotionEvent.ACTION_MOVE:
break;
case MotionEvent.ACTION_CANCEL:
break;
default:
break;
} return super.onTouchEvent(event);
} public class TouchEventCountThread implements Runnable {
public int touchCount = 0;
public boolean isLongClick = false; @Override
public void run() {
Message msg = new Message();
if(0 == touchCount){ // long click
isLongClick = true;
} else {
msg.arg1 = touchCount;
mTouchEventHandler.sendMessage(msg);
touchCount = 0;
}
}
} public class TouchEventHandler extends Handler { @Override
public void handleMessage(Message msg) {
Toast.makeText(mContext, "touch " + msg.arg1 + " time.", Toast.LENGTH_SHORT).show();
}
} class MyThread extends Thread { @Override
public void run() {
super.run();
while (mNotDestroy) {
if (mStartChange) {
postInvalidate();
try {
Thread.sleep(500);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
} public void init() {
mContext = getContext();
bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.ic_launcher);
} public void setText(String mText) {
this.mText = mText;
} public void setStartChange(boolean mStartChange) {
this.mStartChange = mStartChange;
} public boolean getStartChange() {
return this.mStartChange;
}
}

attrs.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
<declare-styleable name="MyView">
<attr name="text" format="string"/>
<attr name="startChange" format="boolean"/>
</declare-styleable></resources>

postDelayed方法最终是靠 Handler 的 postDelayed 方法实现原理如下

public final boolean postDelayed(Runnable r, long delayMillis)
{
return sendMessageDelayed(getPostMessage(r), delayMillis);
} public final boolean sendMessageDelayed(Message msg, long delayMillis)
{
if (delayMillis < 0) {
delayMillis = 0;
}
return sendMessageAtTime(msg, SystemClock.uptimeMillis() + delayMillis);
} public boolean sendMessageAtTime(Message msg, long uptimeMillis) {
MessageQueue queue = mQueue;
if (queue == null) {
RuntimeException e = new RuntimeException(
this + " sendMessageAtTime() called with no mQueue");
Log.w("Looper", e.getMessage(), e);
return false;
}
return enqueueMessage(queue, msg, uptimeMillis); // 然后在MessageQueue中会比较时间顺序
}