Android Moveview滑屏移动视图类完整实例

本文示例所述程序为一个android moveview移动视图类。其主要实现主屏左右滑屏拖动功能，并适时显示拖动时候屏幕的显示情况，该代码中还包括完整的逻辑。其完整代码如下：

import android.study.shift.itemview;
import android.study.shift.mainview;
import android.study.shift.moveview;
import android.content.context;
import android.os.handler;
import android.os.message;
import android.util.attributeset;
import android.util.log;
import android.view.motionevent;
import android.view.view;
import android.view.viewgroup;
import android.view.view.measurespec;
public class moveview extends viewgroup{
 private final static int touch_state_rest = 0;
 private final static int touch_state_moving = 1;
 private final static int move_to_left = 1;
 //private final static int move_to_right = 2;
 private final static int move_to_rest = 0;
 public final static int main = 0;
 public final static int left = 1;
 public final static int right = 2;
 private int touch_state = touch_state_rest;
 private int move_state = move_to_rest;
 private int now_state = main;
 private final float width_rate = 0.18f;
 private mainview main_show_view;
 private itemview left_show_view;
 private int min_distance = 30;//此处只是初始化为30 ，其实不起作用
 private int screen_w;
 private int screen_h;
 private int move_x_v;
 private boolean isaimationmoving = false;
 private handler mhandler = new handler() {
 public void handlemessage(message msg) {//处理消息
  synchronized (moveview.this) {//同步
  isaimationmoving = true;
  int move_change = (int) (screen_w * width_rate / 5);
  int left = main_show_view.getview().getleft();
  if (msg.what == 1) {//主屏在向右拖曳。。。
   move(move_change + left);//参数为拖出来后主屏的坐标。
  }
  if (msg.what == 11) {
   isaimationmoving = false;
   movetoleft(false); //满足可以显示的要求开始显示，false只是一个判定条件，以区别按钮起的效果
  }
  if (msg.what == 2) {//代表主屏向左在拖曳。。。
   move(-1 * move_change + left);
  }
  if (msg.what == 12) {
   isaimationmoving = false;
   //movetoright(false);
  }
  if (msg.what == 0) {
   if (now_state == left) {//如果现在已经显示左边
   move(-1 * move_x_v);//那么还原成主屏
   } else {
   move(move_x_v);
   }
  }
  if (msg.what == 10) {
   isaimationmoving = false;
   movetomain(false);
  }
  }
 }
 };
 public moveview(context context) {
 super(context);
 }
 public moveview(context context, attributeset attrs) {
 super(context, attrs);
 }
 public moveview(context context, attributeset attrs, int defstyle) {
 super(context, attrs, defstyle);
 }
 public void initview() {
 if (main_show_view == null) {
  main_show_view = new mainview(this.getcontext(), this);
  left_show_view = new itemview(this.getcontext());
  //right_show_view = new itemview(this.getcontext(), "aaa");
 }
 this.addview(left_show_view.getview());
 //this.addview(right_show_view.getview());
 this.addview(main_show_view.getview());
 }
 public void initcontent() {
 }
 public void move(int start) {//本函数显示拖动的时候屏幕的显示情况。
 int left = main_show_view.getview().getleft();//left代表主屏左边缘的位置坐标。
 if (now_state == main) {
  if (left > 0) {//如果屏幕的左边被移向右，则left变成正数
  if (move_state != move_to_left) {
   move_state = move_to_left;
  }
  left_show_view.getview().setvisibility(view.visible);//设置左边可见
  //right_show_view.getview().setvisibility(view.gone);
  } //else if (left < 0) {//如果屏幕的左边被移向左，则left变成负数
  //if (move_state != move_to_right) {
  // move_state = move_to_right;
  //}
  //right_show_view.getview().setvisibility(view.visible);
  //left_show_view.getview().setvisibility(view.gone);
  //}
   else {
  move_state = move_to_rest;
  }
  main_show_view.getview().layout(start, 0, start + screen_w,
   screen_h);//参数依次为左、上、右、下。
 } else {
  left = (int) (screen_w * width_rate);//left为左边应该留出的控件空间，或者主屏左边应该在的位置
  if (now_state == right) {
  left = -1 * left;//若状态是在右边空出来，则主屏的左边为负数
  }
  left = left + start;
  main_show_view.getview().layout(left, 0, left + screen_w, screen_h);
 }
 }
 @override
 protected void onlayout(boolean arg0, int arg1, int arg2, int arg3, int arg4) {
 if (move_state == move_to_rest) {
  if (now_state == main) {
  int w = (int) (screen_w * width_rate);//留下预定的宽度，显示各个view的参数设置。
  main_show_view.getview().layout(0, 0, screen_w, screen_h);
  left_show_view.getview().layout(0, 0, w, screen_h);
  } else if (now_state == left) {
  movetoleft(false);
  } else {
  }
 }
 }
 protected void onmeasure(int widthmeasurespec, int heightmeasurespec) {
 main_show_view.getview().measure(widthmeasurespec, heightmeasurespec);
 left_show_view.getview().measure(measurespec.unspecified,//unspecified为未指定的
  heightmeasurespec);
 left_show_view.setwidth((int) (screen_w * width_rate));//设置view宽度
 super.onmeasure(widthmeasurespec, heightmeasurespec);//调用父类的构造函数
 }
 private int start_x;
 private int start_y;
 private boolean ismoved;
 public boolean dispatchtouchevent(motionevent ev) {//分发触摸消息事件
 if (isaimationmoving) {
  return super.dispatchtouchevent(ev);
 } else {
  int action = ev.getaction();
  float x = ev.getx();
  float y = ev.gety();
  switch (action) {
  case motionevent.action_down:
  super.dispatchtouchevent(ev);
  start_y = (int) y;
  move_x_v = 0;
  if (this.touch_state == touch_state_rest) {
   this.touch_state = touch_state_moving;
   start_x = (int) x;
   ismoved = false;
   move_state = move_to_rest;
  }
  break;
  case motionevent.action_move:
  int last_y = (int) y;
  int last_x = (int) x;
  super.dispatchtouchevent(ev);
  if (!ismoved) {
   if (math.abs(last_y - start_y) > math.abs(last_x - start_x)) {//如果y上面移动的距离大于x上面移动的距离。
   super.ontouchevent(ev);
   return true;
   } else {//x移动距离大于y
   if (math.abs(last_x - start_x) > 5) {//x移动距离大于5就被认为移动了
    ismoved = true;
   }
   }
  }
  if (ismoved) {
   if (this.touch_state == touch_state_moving) {
   if (math.abs(last_x - start_x) > 10) {//如果移动的x距离大于10
    int left = main_show_view.getview().getleft();
    log.d("msg", "left:" + left);
    log.d("msg", "x:" + last_x);
    ismoved = true;
    int move_x = last_x - start_x;
    if (move_x > 0 && now_state == left) {//方向正确的移动才算是移动的状态
    ismoved = false;
    break;
    }
    if (move_x < 0 && now_state == right) {//如果现在在显示右边，那么再向右移就不反应。
    ismoved = false;
    break;
    }
    if (move_x < 0 && now_state ==main){//如果现在在主屏，向右移动也是无效的
    ismoved = false;
    break;
    }
    if (move_x > 234 && now_state ==main){
    ismoved = true;//设置为true那么移动还是发生了，break之后还是会在actionup中起作用
    break;//break之后不会执行下面的move()语句,
    }
    if (move_x < -234 && now_state ==left){
    ismoved = true;
    break;
    }
    move(move_x);//以移动的距离为参数调用move（）实现移动的动态显示
   }
   }
   return false;
  }
  break;
  case motionevent.action_up://
  if (this.touch_state == touch_state_moving) {
   if (ismoved) {
   last_x = (int) x;
   if (math.abs(last_x - start_x) > min_distance) {//
    if (now_state == main) {
    if (move_state == move_to_left) {
     this.movetoleft(false);
    }
    } else {
    this.movetomain(false);
    }
   } else {  //
    if (now_state == main) {
    this.movetomain(false);
    }
    if (now_state == left) {
    this.movetoleft(false);
    }
    if (now_state == right) {
    //this.movetoright(false);
    }
   }
   move_state = move_to_rest;
   }  else {
   super.dispatchtouchevent(ev);
   this.touch_state = touch_state_rest;
   return false;//
   }
  }
  super.ontouchevent(ev);
  this.touch_state = touch_state_rest;
  break;
  }
  return true;
 }
 }
 public boolean getismoved() {
 return ismoved;
 }
 public void movetoleft(boolean b) {
 if (!b) {
  int move_x = (int) (screen_w * width_rate);
  left_show_view.getview().layout(0, 0, screen_w, screen_h);
  //right_show_view.getview().layout(move_x, 0, move_x * 2, screen_h);
  main_show_view.getview().layout(move_x, 0, move_x + screen_w,
   screen_h);
  now_state = left;//为什么现在又把now_state赋值为left？
 }
//  else {//else以及括号中的语句都是为原来的按钮准备的。。。
//  mhandler.postdelayed(new runnable() {//一个新的可运行的函数
//
//  @override
//  public void run() {
//   int move_change = (int) (screen_w * width_rate / 5);//五分之一要显示的宽度
//   int left = (int) (screen_w * width_rate - main_show_view
//    .getview().getleft());//getleft()返回的是主屏左边缘离左边的距离
//   message msg = new message();
//   if (left > move_change) {//括号里面不懂，起什么作用？
//   msg.what = 1;
//   mhandler.sendmessage(msg);
//   mhandler.postdelayed(this, 10);//又调用自己，基本上非要是小于关系
//   } else {
//   msg.what = 11;
//   mhandler.sendmessage(msg);
//   mhandler.removecallbacks(this);
//   }
//  }
//  }, 0);
// }
 }
 public void movetomain(boolean b) {
 if (!b) {
  //right_show_view.getview().setvisibility(view.visible);
  left_show_view.getview().setvisibility(view.visible);
  int w = (int) (screen_w * width_rate);
  main_show_view.getview().layout(0, 0, screen_w, screen_h);
  left_show_view.getview().layout(0, 0, w, screen_h);
  now_state = main;
 }
 }
 public void initscreensize(int w, int h) {
 this.screen_w = w;
 this.screen_h = h;
 log.d("screen", "screen_w:" + w);
 this.setkeepscreenon(true);
 min_distance = (int) (screen_w / 12.0);//min_distance在这里又被初始化为屏幕的一个比例大小
 initview();
 initcontent();
 movetomain(false);
 }
 public int getnowstate() {
 return this.now_state;
 }
}