Android:滑动

package com.example.textcolordemo.drag;

import android.content.Context;
import android.graphics.Color;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.view.ViewGroup.MarginLayoutParams;

public class DragView1 extends View {
private int lastX ,lastY,lastL,lastR,lastT,lastB;

public DragView1(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
super(context, attrs, defStyleAttr, defStyleRes);
setBackgroundColor(Color.YELLOW);
}

public DragView1(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
setBackgroundColor(Color.YELLOW);
}

public DragView1(Context context, AttributeSet attrs) {
super(context, attrs);
setBackgroundColor(Color.YELLOW);
}

@Override
public boolean onTouchEvent(MotionEvent event) {

int x = (int) event.getX();
int y = (int) event.getY();
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
lastX = x;
lastY = y;
lastL= getLeft();
lastR = getRight();
lastB = getBottom();
lastT= getTop();
break;
case MotionEvent.ACTION_MOVE:
int offsetX = x - lastX;
int offsetY = y - lastY;
//方法1： layout
layout(getLeft()+offsetX, getTop()+offsetY, getRight()+offsetX, getBottom()+offsetY);
//方法2： setLayoutParams
ViewGroup.MarginLayoutParams lp = (MarginLayoutParams) getLayoutParams();
lp.leftMargin = getLeft()+offsetX;
lp.topMargin = getTop()+offsetY;
setLayoutParams(lp);
//方法3：scrollBy 移动ViewGroup中的子View或者是View中的内容
((View) getParent()).scrollBy(-offsetX, -offsetY);
//方法4： api封装好的方法
offsetLeftAndRight(offsetX);
offsetTopAndBottom(offsetY);
break;
case MotionEvent.ACTION_UP:
layout(lastL, lastT, lastR, lastB);
break;
default:
break;
}
return true;
}

}

package com.example.textcolordemo.drag;

import android.animation.ObjectAnimator;
import android.animation.PropertyValuesHolder;
import android.content.Context;
import android.graphics.Color;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import android.widget.Scroller;

public class DragView_Scroller extends View {
private int lastX ,lastY,lastL,lastR,lastT,lastB;
private Scroller mScroller;

public DragView_Scroller(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
super(context, attrs, defStyleAttr, defStyleRes);
setBackgroundColor(Color.YELLOW);
mScroller = new Scroller(context);
}

public DragView_Scroller(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
setBackgroundColor(Color.YELLOW);
mScroller = new Scroller(context);
}

public DragView_Scroller(Context context, AttributeSet attrs) {
super(context, attrs);
setBackgroundColor(Color.YELLOW);
mScroller = new Scroller(context);
}

@Override
public void computeScroll() {
super.computeScroll();
if (mScroller.computeScrollOffset()) {
((View)getParent()).scrollTo(mScroller.getCurrX(), mScroller.getCurrY());
invalidate();
}
}

@Override
public boolean onTouchEvent(MotionEvent event) {

int x = (int) event.getX();
int y = (int) event.getY();
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
lastX = x;
lastY = y;
lastL= getLeft();
lastR = getRight();
lastB = getBottom();
lastT= getTop();
break;
case MotionEvent.ACTION_MOVE:
int offsetX = x - lastX;
int offsetY = y - lastY;
((View) getParent()).scrollBy(-offsetX, -offsetY);//使父布局中的所有内容移动
break;
case MotionEvent.ACTION_UP:
View vg = ((View)getParent());
mScroller .startScroll(vg.getScrollX(), vg.getScrollY(), -vg.getScrollX(), (int) -vg.getScrollY());
invalidate();
break;
default:
break;
}
return true;
}

}