问题描述

为什么我拖拽后的控件回不去！！帮忙看下代码是什么问题！！谢谢

这是JAVA代码

 package com.example.test;

import com.example.test1.R;

import android.annotation.SuppressLint;
import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.Display;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
import android.widget.ImageView;

public class Main extends Activity implements OnTouchListener{
    ImageView[] iv = new ImageView[6];
    int[] index = { R.id.imagevb1, R.id.imagevb2, R.id.imagevb3, R.id.imagevb4,
            R.id.imagevb5 ,R.id.imagevb6};
    int screenWidth, screenHeight;//界面的大小
    int lastX, lastY;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        for (int i = 0; i < index.length; i++) {
            iv[i] = (ImageView) findViewById(index[i]);
            iv[i].setOnTouchListener(this);
        }
        Display dis = this.getWindowManager().getDefaultDisplay();
        screenWidth = dis.getWidth();
        screenHeight = dis.getHeight();
    }
    @Override
    public boolean onTouch(View v, MotionEvent event) {
        switch (v.getId()) {
        case R.id.imagevb1:
            get(iv[0], event);
            break;
        case R.id.imagevb2:
            get(iv[1], event);
            break;
        case R.id.imagevb3:
            get(iv[2], event);
            break;
        case R.id.imagevb4:
            get(iv[3], event);
            break;
        case R.id.imagevb5:
            get(iv[4], event);
            break;
        case R.id.imagevb6:
            get(iv[5], event);
            break;
        }
        return false;
    }

    int a1, a2, a3, a4;

    public void get(ImageView v, MotionEvent event) {
        switch (event.getAction()) {
        case MotionEvent.ACTION_DOWN:// 表示用户开始触摸
            lastX = (int) event.getRawX();
            lastY = (int) event.getRawY();
            a1 = v.getLeft();
            a2 = v.getTop();
            a3 = v.getBottom();
            a4 = v.getRight();
            break;
        case MotionEvent.ACTION_MOVE:// 表示用户在移动(手指或者其他)
            int dx = (int) event.getRawX() - lastX;
            int dy = (int) event.getRawY() - lastY;
            int left = v.getLeft() + dx;
            int top = v.getTop() + dy;
            int right = v.getRight() + dx;
            int bottom = v.getBottom() + dy;
            if (left < 0) {
                left = 0;
                right = left + v.getWidth();
            }
            if (right > screenWidth) {
                right = screenWidth;
                left = right - v.getWidth();
            }
            if (top < 0) {
                top = 0;
                bottom = top + v.getHeight();
            }
            if (bottom > screenHeight) {
                bottom = screenHeight;
                top = bottom - v.getHeight();
            }
            v.layout(left, top, right, bottom);
            lastX = (int) event.getRawX();
            lastY = (int) event.getRawY();
            break;
        case MotionEvent.ACTION_UP:// 表示用户抬起了手指
            v.layout(a1, a2, a3, a4);
            break;

        }

    }

}

**这是Xml布局文件**

 <FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/FrameLayout1"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >
    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent" >

        <ImageView
            android:id="@+id/imagevb1"
            android:layout_width="40dp"
            android:layout_height="40dp"
            android:layout_alignParentLeft="true"
            android:layout_alignParentTop="true"
            android:layout_margin="12dp"
            android:layout_marginLeft="146dp"
            android:layout_marginTop="30dp"
            android:clickable="true"
            android:src="@drawable/block0" />

        <ImageView
            android:id="@+id/imagevb2"
            android:layout_width="80dp"
            android:layout_height="40dp"
            android:layout_alignParentLeft="true"
            android:layout_below="@+id/imagevb1"
            android:layout_margin="12dp"
            android:layout_marginLeft="146dp"
            android:layout_marginTop="30dp"
            android:clickable="true"
            android:src="@drawable/block1" />

        <ImageView
            android:id="@+id/imagevb3"
            android:layout_width="40dp"
            android:layout_height="80dp"
            android:layout_alignParentLeft="true"
            android:layout_below="@+id/imagevb2"
            android:layout_margin="12dp"
            android:layout_marginLeft="146dp"
            android:layout_marginTop="30dp"
            android:clickable="true"
            android:src="@drawable/block2" />

        <ImageView
            android:id="@+id/imagevb4"
            android:layout_width="80dp"
            android:layout_height="80dp"
            android:layout_alignParentLeft="true"
            android:layout_below="@+id/imagevb3"
            android:layout_margin="12dp"
            android:layout_marginLeft="146dp"
            android:layout_marginTop="30dp"
            android:clickable="true"
            android:src="@drawable/block3" />

        <ImageView
            android:id="@+id/imagevb5"
            android:layout_width="120dp"
            android:layout_height="120dp"
            android:layout_alignParentLeft="true"
            android:layout_below="@+id/imagevb4"
            android:layout_margin="12dp"
            android:layout_marginLeft="146dp"
            android:layout_marginTop="30dp"
            android:clickable="true"
            android:src="@drawable/block4" />

        <ImageView
            android:id="@+id/imagevb6"
            android:layout_width="80dp"
            android:layout_height="120dp"
            android:layout_alignParentLeft="true"
            android:layout_below="@+id/imagevb5"
            android:layout_margin="12dp"
            android:layout_marginLeft="146dp"
            android:layout_marginTop="30dp"
            android:clickable="true"
            android:src="@drawable/block5" />
    </RelativeLayout>

</FrameLayout>

问题：我要的效果是我手一松开，我拖拽的控件就回到原来的位置，但是现在只有第一个可以做到松开就回去。其他控件可以拖动但是手一松开就消失了！！没错，消失了！！求大家帮忙看看是那里出错了！！！

解决方案

粗略的看了下，貌似第一个控件有这个 android:layout_alignParentTop="true" ，与这个有关系吗？