ANDROID笔记:滑动关闭Fragment的简单实现

主要代码:(有注释)

package com.example.checkboxtest;



import android.annotation.SuppressLint;

import android.content.Context;

import android.graphics.Canvas;

import android.graphics.Color;

import android.os.Handler;

import android.os.Message;

import android.util.AttributeSet;

import android.view.MotionEvent;

import android.view.View;

import android.view.ViewGroup;

import android.widget.Toast;



public class MyView extends ViewGroup {

    View leftView = null;

    View rightView = null;



    public MyView(Context context, AttributeSet attrs) {

        super(context, attrs);

        View view = new View(context, attrs);

        view.setBackgroundColor(Color.BLACK);

        this.addView(view, 0);

    }



    /**

     * 测量

     */

    @SuppressLint("DrawAllocation")

    @Override

    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {

        if (getChildCount() != 2) {

            try {

                // 自定义Exception

                throw new Exception() {

                    @Override

                    public void printStackTrace() {

                        System.err.println("MyView中只能存在一个View");

                        super.printStackTrace();

                    }



                };

            } catch (Exception e) {

                e.printStackTrace();

            }

        }

        leftView = getChildAt(0);

        // 设置leftview的高和宽

        leftView.measure(widthMeasureSpec, heightMeasureSpec);

        rightView = getChildAt(1);

        // 设置rightview的高和宽

        rightView.measure(widthMeasureSpec, heightMeasureSpec);

        super.onMeasure(widthMeasureSpec, heightMeasureSpec);

    }



    /**

     * 布局

     */

    @SuppressLint("NewApi")

    @Override

    protected void onLayout(boolean changed, int l, int t, int r, int b) {

        System.out.println(l + "," + t + "," + r + "," + b);

        if (leftView != null & rightView != null) {

            // 设置leftview的位置,在屏幕右侧(初始不可见)

            leftView.layout(-r, 0, 0, b);

            // 设置rightView的位置,在屏幕中

            rightView.layout(l, t, r, b);

        }

    }



    @Override

    protected void onDraw(Canvas canvas) {

        super.onDraw(canvas);



    }



    @SuppressLint("NewApi")

    @Override

    public boolean onTouchEvent(MotionEvent event) {

        final float X = event.getX();

        float Y = event.getY();

        switch (event.getAction()) {



        case MotionEvent.ACTION_MOVE:

            System.out.println("X:" + X);

            if (X < 100) {

                scrollTo(0, 0);

            } else if (X > rightView.getMeasuredWidth() - 100) {// 当用户滑动至离右边缘100时,页面关闭

                new Thread(new Runnable() {// 新建线程,滑动关闭

                            @Override

                            public void run() {

                                for (int i = 0;; i++) {

                                    try {

                                        Thread.sleep(10);// rightView每隔10ms右移3,保证滑动流畅

                                    } catch (InterruptedException e) {

                                        e.printStackTrace();

                                    }

                                    int len = (int) (X + 3 * i);

                                    // System.out.println("len:" + len);

                                    Message message = new Message();// android中非UI线程不允许直接操作控件,可以将消息发送至主线程的handler类

                                    if (len >= rightView.getMeasuredWidth()) {

                                        message.what = 1;

                                        handler.sendMessage(message);// 发送消息

                                                                        // 关闭View

                                        break;

                                    } else {

                                        message.what = 0; // 发送消息 自动滑动

                                        handler.sendMessage(message);

                                    }

                                }

                            }

                        }).start();

            } else {

                scrollTo((int) -X, 0);

                // 计算透明度信息

                float alpha = (float) (1.0 - (float) (1.0 / 400) * X);

                // System.out.println("alpha:" + al);

                // 设置透明度

                leftView.setAlpha(alpha);

            }

            break;

        }

        // 设置true,消费event事件,不在向外传递

        return true;

    }



    @SuppressLint("HandlerLeak")

    Handler handler = new Handler() {

        @SuppressLint("NewApi")

        @Override

        public void handleMessage(Message msg) {

            if (msg.what == 0) {

                scrollBy(-3, 0);// viewgroup向右滑动3

            } else if (msg.what == 1) {

                Toast.makeText(getContext(), "关闭", 50).show();

                setVisibility(View.GONE);// 设置viewgroup不可见(隐藏)

            }

        }



    };

}

使用:

  <com.example.checkboxtest.MyView

        android:layout_width="fill_parent"

        android:layout_height="fill_parent" >



        <View

            android:id="@+id/rightview"

            android:layout_width="fill_parent"

            android:layout_height="fill_parent"

            android:background="#ff0000" />

    </com.example.checkboxtest.MyView>

要显示底下的activity界面需要使用Fragment的add方法

//新建一个Fragment

Fragment bFragment = new BFragment();

getFragmentManager().beginTransaction().add(R.id.fragment, bFragment).commit();

工程源码下载:http://pan.baidu.com/share/link?shareid=866490907&uk=1141451701